Chapter 1 Seeking for a
sustainable way of living
- current progress of the project
the word "sustainable" has often been used. It is used in this home
page with a meaning of pursuing a happy human life for as long as the
sun exists, relying on its energy. The decision to undertake this
project was made on New Year's Day of 1990 as a New Year’s
resolution. When I was involved in measuring public nuisances,
especially noise pollution, the problems were of a local nature. Now
problems are global. I could not understand why society was unconcerned
and did not pay much attention to these issues. I started to think that
we have to find practical methods and find them right now. In the
beginning, the plan was to finish the project in ten years. The project
is not yet completed and I want to report on the past 15
work of our sure realization of sustainable living. However, the things
I still want to do are increasing and I can not handle all of them by
myself. Frankly speaking, I need others help with the project.
this age of mine I am interested in the world after death more than
anything. What kind of world is waiting for me? There is an
inexpressible anxiety, however this is not fear but interest in where I
go, because I believe that it is a space continuous from the present
world. The discussion of this question has taken place in the past
since ancient times and will continue for enormous time. God gives us a
great energy source in the sun, the warm embrace of the earth and the
universe to help solve the question. Because it is not known when we
will find the solution to this ancient question, we need to keep our
precious earth safe in order to be able to think through the solution.
In such a way I define the word "sustainable" broadly. Therefore, we
need to recognize that solar energy is the only reliable energy source
and is sufficient to supply all the energy that we use. It is estimated
that the sun gives us 15,000 times the energy that all human beings
use. In other words, we can keep living as long as the sun exists and
we co-operate to solve the last subject given by God.
individual should think by himself, with his own creation in mind,
about the philosophy that has usually been created by great religions,
and try to meld them to find his individual solution to this subject.
In such a way, instead of being persuaded to believe any particular
philosophy, one has to think deeply based on one’s individual
creation. This should compose a fundamental tenet of individualism,
which is never selfish.
The latest point at which
the earth will
perish is when solar energy ends. At this moment any creature on the
earth will die. Where will our souls go then? There will need to be a
new start towards finding a new world for human beings. Not wandering
in the universe, we need to establish a firm destiny and purpose. This
will be the preparation for a new start.The thought that everything
turns to nothingness at the end of the earth is the same process as
bacteria or fungi finishing their lives after they consume all the
energy of organic food. A human being must have a more superior
existence or else we can not have any real joy and meaning in life.
is said that joy is an impulse from the gods. It is obtained only on
earth through a self which will not exist in the next world. Romance,
arts, music, literature, science all come through ourselves. Therefore,
we have to have as many joys as possible, enhance our spirit, our mind,
our thought and make a new start in the next plane. However, these joys
are accepted and allowed only when sustainable lives are established.
of the following items are technological, however most of them are
common sense. Accordingly, in defining sustainability clearly, I want
to further a wider discussion.
Another point I wish
is that most technologies of the past relied on and were developed by
using easily obtainable energy, leaving much environmental pollution
and contamination. When fossil energy is used up (it is said that this
will be within the next 40 years), most of these technologies will not
be useful any more. We will have to go back some years and start to
establish new sciences in order to realize a sustainable life whereby
we rely on solar energy. We need to go back in time and make changes at
the point where we find the forgotten and take a new direction. As I
will point out later, when we aim at having sustainable lives we notice
there are a lot of hidden scientific regions to be developed around us.
I am originally an Acoustician who has been involved in Architectural
Environmental Engineering in a Department of Architecture. Otherwise, I
am a common person. Though my shallow scientific knowledge may bring
scornful laughs, I want to emphasize on this homepage that there is a
new direction towards which we should co-operate.
you look at
it from a practical point of view, one should work for oneself not for
anybody else. If one works to a certain degree, nature will help one a
lot. Finally an individual becomes free, independent and liberated from
external powers, and can establish oneself. This life-style brings a
dramatic change, but it is not a revolution because this word evokes a
power struggle. A sustainable life is not one for power struggles, but
for self reform. To live sustainably is to physically find a living way
until the sun finishes its life. For that, we have to live modestly,
using natural energy, not contaminating the earth, living
self-sufficiently through organic farming. These things are essential.
A social structure must be constructed with a low hierarchal structure
which is based on the spirit of social service. As a result, there will
naturally not be wars for greed or power struggles.
broader definition, if a human being as an individual establishes a
sustainable life in nature, he can make his or her own creative life.
His creation will live successively in the next plane and should be
developed in the form of spiritual activity to find continuity. Then,
even when the sun dies, we will be able to proceed to the next plane.
environment has indeed become bad. We know that there have been many
extinctions of creatures, the greenhouse effect, unusual climate
changes, the land has been filled full of poisonous substances and so
on. A man who clearly predicted the present situation 150 years ago was
American Indian chief, Seattle. He replied to the then American
President in 1854, when he was asked by the president to sell his
"This earth is precious"
can you buy or sell the sky, the warmth of the land? The idea is
strange to us
If we do not own the freshness of the air and
the sparkle of the water, how can you buy them?
Every part of the earth is sacred to my people.
shinning pine needle, every sandy shore, every mist in the dark woods,
every clearing and humming insect is holy in the memory and experience
of my people. The sap which courses through the trees carries the
memories of the red man.
The white man's dead forget the
of their birth when they go to walk among the stars. Our dead never
forget this beautiful earth, for it is the mother of the red man.
are a part of the earth and it is a part of us.
flowers are our sisters; the deer, the horse, the great eagle, these
are our brothers.
The rocky crests, the juices in the meadows,
the body heat of the pony, and man - all belong to the same family.
when the Great Chief in Washington sends word that he wishes to buy our
land, he asks much of us. The Great Chief sends word he will reserve us
a place so that we can live comfortably to ourselves.
be our father and we will be his children. So we will consider his
offer to buy our land.
But it will not be easy. For this land
is sacred to us.
This shining water that moves in the streams
and rivers is not just water but the blood of our ancestors.
we sell you land, you must remember that it is sacred, and you must
teach your children that it is sacred and that each ghostly reflection
in the clear water of the lakes tells of events and memories in the
life of my people.
The water's murmur is the voice of my
rivers are our brothers, they quench our thirst. The rivers carry our
canoes, and feed our children. If we sell you our land, you must
remember, and teach your children, that the rivers are our brothers,
and yours, and you must henceforth give the rivers the kindness you
would give any brother.
We know that the white man does not
understand our ways. One portion of land is the same to him as the
next, for he is a stranger who comes in the night and takes from the
land whatever he needs.
The earth is not his brother, but his
enemy, and when he has conquered it he moves on.
He leaves his
father's graves behind, and he does not care. He kidnaps the earth from
his children, and he does not care.
father's grave and his children's birthright are forgotten. He treats
his mother, the earth, and his brother, the sky, as things to be
bought, plundered, sold like sheep or bright beads.
appetite will devour the earth and leave behind only a desert.
don't know. Our ways are different from your ways.
sight of your cities pains the eyes of the red man. But perhaps it is
because the red man is a savage and does not understand.
quiet place in the white man's cities. No place to hear the unfurling
of leaves in spring, or the rustle of an insect's wings.
perhaps it is because I am a savage and do not understand.
clatter only seems to insult the ears. and what is there to life if a
man can not hear the lonely cry of the whip-poor-will or the arguments
of the frogs around a pond at night? I am a red man and do not
The Indian prefers the soft sound of the wind
over the face of a pond, and the smell of the wind itself, cleaned by a
midday rain, or scented with the pinion pine.
air is precious to the red man, for all things share the same breath -
the beast, the tree, the man, they all share the same breath.
white man does not seem to notice the air he breathes. Like a man dying
for many days he is numb to the stench.
if we sell you our land, you must remember that the air is precious to
us, that the air shares its spirit with all the life it supports. The
wind that gave our grandfather his first breath also receives his last
And if we sell you our land, you must keep it apart and
sacred, as a place where even the white man can go to taste the wind
that is sweetened by the meadow's flowers.
we will consider your offer to buy our land. If we decide to accept, I
will make one condition. The white man must treat the beasts of this
land as his brothers.
I am a savage and I do not understand
any other way.
I have seen a thousand rotting buffaloes on the
prairie, left by the white man who shot them from a passing train.
am a savage and I do not understand how the smoking iron horse can be
more important than the buffalo that we kill only to stay alive.
is man without beasts? If all the beasts were gone, man would die from
a great loneliness of spirit.
For whatever happens to the
beasts, soon happens to man. All things are connected.
must teach your children that the ground beneath their feet is the
ashes of your grandfathers. So that they will respect the land, tell
your children that the earth is rich with the lives of our kin.
your children what we have taught our children that the earth is our
Whatever befalls the earth, befalls the sons of the
earth, if men spit upon the ground, they spit upon themselves.
we know; the earth does not belong to man, man belongs to the earth.
This we know.
All things are connected like the blood which
unites one family. All things are connected.
befalls the earth befalls the sons of the earth. Man did not weave the
web of life; he is merely a strand in it. Whatever he does to the web,
he does to himself.
Even the white man, whose God walks and
talks with him as friend to friend, cannot be exempt from the common
We may be brothers after all.
One thing we
know, which the white man may one day discover - our God is the same
may think now that you own Him as you wish to own our land, but you
cannot. He is the God of man, and His compassion is equal for the red
man and the white.
The earth is precious to Him, and to harm
the earth is to heap contempt on its Creator.
whites too shall pass, perhaps sooner than all other tribes.
Contaminate your bed, and you will one night suffocate in your own
But in your perishing you will shine brightly, fired by
strength of the God who brought you to this land, and for some special
purpose gave you dominion over this land and over the red man.
destiny is a mystery to us, for we do not understand when the buffalo
are slaughtered, the wild horses are tamed, the secret corners of the
forest heavy with scent of many man, and the view of the ripe hills
blotted by talking wires.
Where is the thicket?Gone.
is the eagle?Gone.
The end of living and the beginning of
in his time he foresaw the present state we live in, and he finished
his letter saying, "It is the end of living and the beginning of
survival."Look at our daily attitudes in the way we carefully avoid
foods with additives, the way we put water filters on water from the
main civic supply. We have to make a lot of effort just to survive.
Chief Seattle was quite right. When I resigned from Kansai University
at age 60, I made my students read his letter in class. I also said to
them that there soon might come such a time that we will have to live
with a bottle of mineral water in our hand and a cylinder of fresh air
on our back.
It is strange. Surviving early
eating hardly any food (including the stalks of sweet potatoes),
experiencing rapid economical growth and living at the zenith of the
materialistic world, why do I miss my early days? The smell of grass in
the field where I chased dragonflies and grasshoppers, the clear sea
water where I enjoyed fishing and swimming, not only Chief Seattle but
also I feel very nostalgic, missing the time when life was full of
nature. Nature's persuasion is great. When a new large building was
constructed on my campus, I expected the surrounding trees to grow
faster. It is a similar feeling to Seattle’s.
younger it was normal to use a fan or if lucky, an electrical fan in
summer and to heat in winter by using a 'hibachi' (a personal heater)
and by wearing thick clothes. On a summer night after taking part in
'bon-odori' dancing we enjoyed eating a cool watermelon which was kept
in the well, and jumped into a 'futon' bed shaking the mosquito screen
in order to sleep soundly in the night coolness, shaking off the
fatigue from the hot summer daytime.This brings warm memories back to
me. All these things are gone now and we do not know who, where and how
they were taken away.
Chief Seattle criticized materialistic
attitudes and technologies, and predicted modern nuisances and global
contamination. His foresight is profound and wonderful. It was
apprehension against greed and technology given by a person who lived
with nature. Can the solutions to protecting our precious earth only
come from people who have touch points with nature and feel it closely?
how has Architecture in Japan has contributed to society? High-rise
buildings and skyscrapers look gorgeous at a glance, but how about
houses for people? The author has travelled to a lot of countries, but
has never seen such poor houses as in Japan. Cheap construction, poor
design and so on. Electrical equipment and air-conditioning systems
make them look rich, but they have no greenery and their indoor spaces
are very poor. When fossil energy is finished, they will change into
slums. In high-rise buildings, which are created by "new construction
materials", huge amounts of energy have to be used for the
air-conditioning system, lifts and so on, from when it is first
designed. When fossil energy is finished, they will be turned into
ruins. Japan is not a wide country. However, the Japanese are packed
into 4% of their land and look to cheap conveniences for results. Every
building uses similar "new building materials". If it is cheap and has
appealing points, it conquers the market. Even if it is hazardous and
not friendly to nature, they start to use it from North to South.
was a small international conference on "Earth building" at Auckland
University in November 1990. At the meeting were people who respect
nature - enthusiasts or even fanatics of sun dried clay brick, adobe
and earth building. One of the main subjects was nature-friendly
building materials. It was reported that new building materials can
badly affect our health. Damage to adobe buildings by earthquakes was
reported from Ecuador, Turkey, and New Zealand etc.
give a lecture on architectural environmental planning, but was asked
to do one on Japanese earth buildings which meant a quick study. I
talked about how cobbed walls over a 'komai' bamboo net stood well
against many earthquakes, as shown in Japan’s history, and
the thermal insulation of double cobbed walls with an air space in
between and good heat capacity can give us wonderful building
materials. I also talked about the thatched roofs commonly used from
tropical to cold regions. We should review through scientific analysis
traditional vernacular materials and methods of construction - and not
only of walls and roofs.
It is necessary to "find"
nature-friendly materials are. "find" was a theme given by the
editorial board of the Architectural Institute of Japan. My comment was
published on Vol.106, No.1313, 1991(May). It is reproduced here with a
It is clear that in Osaka city the yearly
temperature is closely correlated with energy consumption. Exhausted
heat and stored heat in concrete structures create a heat island. When
we took a subway ride during my childhood in summer, we expected to be
able to travel to a cool place. What is the situation now? Many
air-conditioners are operated at full strength at subway stations. This
is one piece of evidence. I don't know the proportion ofenergy used for
factories, trains, cars, air planes and households, but the household
sector must use not a small amount. Now, Architectural Environmental
Engineering has a great role in this region.
that three dimensional solutions for a sound field, thermal conditions
and a light field are practically obtained. These physical estimations
should be used for Architectural planning through an estimation
function to predict the indoor environment. We have proposed a method
to synthesize these heterogeneous environmental factors, giving a
common subjective scale of 'uncomfortableness'. Details of this are
given in chapter 5. From the quantification there, a thermal
environment, especially in summer, is the dominant factor of them.
Therefore, we started to look at the question of whether it is possible
to have not uncomfortable thermal conditions without disturbing the
natural environment. Namely, the hotter outside, the cooler inside in
summer and the colder outside, the warmer inside in winter. Here, what
we are to "find" is to be able to realize this for an indoor
environment using ground heat.
It is known that
there is a level
that steadily maintains the average air temperature on the surface
about 8 meters below the surface, if the earth has usual thermal
conduction factors. If we could take it up, it is cooler in summer and
warmer in winter. We plan to create buoyancy or lifting power with the
solar energy in the solar room without using any fossil energy. It is
difficult to dig 8 meters deep but 4 meters is practical and possible,
laying cool tubes there and guiding the outside air through into the
basement. In winter, this energy will be collected like windmill
electricity, solar energy, compost fermentation heat and so on, and can
be added to ground heat. We can have a temperature of 26 degrees inside
while it is 34 degrees outside in summer and 12 degrees inside while it
is zero degrees outside in winter according to calculations using the
result of experiments with models. We will experiment at an
experimental house. At the house, the roof will be thatched by grass or
straw, roofed with shingles or combined by them. The western wall will
be cobbed for heat storage and the addition of buoyancy. In addition,
projects on rain water use the output process from a toilet,
contribution of trees on thermal conditions and so on. The house should
be built with nature-friendly materials which nicely return to nature.
In such a way a dream expands.
These projects will
practically with my students at the house, which offers a place to
discuss and experiment with them. The dimensions of a sink, the tread
and rise of a step, the height of a hand rail should not be decided by
a book. Building methods and details for designing a house should be
learnt practically from work at the site too. A few similar discussions
were held in Japan. Unfortunately, the present circumstances there,
which are based on cheap fossil energy use, do not welcome this
attitude, nor bring up and develop them, until it gets to a fatal
extreme. Fortunately, I have some friends in New Zealand with whom I
feel the common basis of understanding and I want to bring back the
results as a message from that country. There are a few other reasons
NZ was selected. Among others, land is not expensive, we can contribute
towards international mutual understanding and the time difference to
Japan is not great.
We have to think of other
reasons why this
kind of concept can not be developed in Japan. The research, study and
education for housing, which is the fundamental shelter for the basic
unit of a society, i.e. a family, is disregarded. Practical activities
in this direction are never seen. For instance, if we look at the
curricula at universities, we notice they are aiming to educate
students to build large sized buildings with mass-produced building
materials. One of the reasons is that there is too much weight put on
Structural Engineering in the distribution of laboratories and staff in
the Department of Architecture. There is only a single specialized
staff member for Structural Engineering out of about twenty staff total
in the Dept of Architecture, Auckland University. In addition, he
teaches the subject using models to explain instead of just theoretical
formulas. They have five staff for Architectural Environmental
Engineering and the other staffs are in the areas of designing and
planning. On the other hand, Structural Engineering in Japan has been
divided and separated by different methodologies and boundary
conditions, and has developed in a different way. It is now at a
certain maturity and should be thinking about how it could serve
Architecture rather than the development of itself. It is only one of
the factors in Architectural Planning. Architecture has to "find" a new
and true direction.
There needs to be more emphasis
and planning a better and more durable house of good quality. Yoshida,
the first Japanese prime minister after World War II, encouraged people
to recover the then ruined country by building factories rather than
houses, while the German prime minister of the same time did the
reverse, promoting housing rather than factories. I used to visit a
friend of mine in Germany for more than thirty years every few years.
Every time I found that he lived much better than I did, say 10 years
ahead of me. I can't compare with him any more because I can't buy a
piece of land in Japan.
Whatever the situation is we must not
let our Architecture "find" the end of the world.
obtained and cheap oil is the target of greedy people and its mass use
creates various social hazards as well as the greenhouse effect. These
greedy economical deeds yield unsolvable and poisonous chemical
substances, poisonous heavy metals produced through the production
process, accumulated radioactive wastes, antibacterials, substances
that cause ozone depletion and so on. Fossil energy is likely to run
out in forty years time. It will apparently leave us decadent and
In the past if it snowed, we would get a snow
the sun was strong, we would use a water reed screen. With a little
work, the situation could be made much better for a lengthy time. We
must not seek to do everything for convenience and too much comfort. We
must not forget to strengthen our immune system through the change of
seasons and to know the joys given by them.
It is known that
energy will finish sooner or later leaving only contamination and
pollution. The construction of a large building consumes a lot of
energy and huge energy amounts are spent there daily. No arguments can
arise on this subject. The end of fossil energy will come earlier and
suddenly due to developing countries also using it in the same way. We
will be thrown into chaos which can be easily imagined, blaming and
swearing at each other. Already weakened immunity will become worse,
human values will continue to decrease, and discrimination will become
How can the present society which
situations be reformed? We can't find any proper way when we construct
a society to rely on and use each other too much. We have to break with
this old way and start to establish a sustainable way of living for
individuals. I think this is the only way that we can choose now. We
need something where the origin is oneself and an individual is free
Some say that we could find new energy
However, it would be just an extension of present decadent concepts. At
the same time, if they were to be found, we would be chained to a
strongly structured society in the same way as now. Reminded of how
wonderful it is to have contact with nature, we shouldget the origin of
a new start there.
In order to develop this concept, we have
establish not qualitative but quantitative insistence, else we will be
washed out by strong economical power and the end result will be
sterile discussions. After precise measurements and their analysis,
this development can be simulated and then quantitative discussions
will follow. We have to know that with a living plan that these results
are only from simulations, and we can have inestimable joy to create
with an awareness of coexisting with nature.
establish a sustainable way of living until we deny greed and return to
living a modest life. For that reason, we have to deeply and seriously
think over the purpose of one’s life. I am not giving this
proposal just to deny the present situation. If we are based on a
sustainable lifestyle relying on solar energy in a low hierarchy
society, we can be free and liberated from power structures, and have a
humane, peaceful and happy life being surrounded by nature. I compare
the meaning of a sustainable life with the present society just for
explanation. If we live in nature, it is evident that effort will be
Even though we are given 15,000 times
that we use, it must be shared with the environment that gives us
wonderful joys. It must be used also for our great surroundings, birds,
fish and animals, flowers, trees and grass, and winds, seas and rivers.
It is said that joy is an impulse from the gods. The existing space
that is created by the gods and its maintenance is absolute. From there
we get the concept to live in a modest way. We must be warned against
using all the solar energy for human beings in luxurious ways, while we
should feel the greatness in the way this huge amount of energy
sustains our earth. Let's understand that we should use only this
1/15,000 and let great nature encourage us to carry out a sustainable
way of living.
At the realization of sustainable
living, if it
is expressed that we can live as long as the sun exists, this is the
root of materialism. We have to be beyond it and develop ourself
spiritually which means a movement to the next plane and its discovery.
These facts and directions must be well understood by our generation as
well as future ones, and education and research are urgently necessary.
The knowledge and habits which are obtained in childhood are accepted
naturally and are not bothersome. If many of following generations aim
at a sustainable way of living, we could get there earlier.
to establish a social system for recycling and reuse and use of our
limited natural resources, even if it is transitional. If they are
mixed, they are just rubbish, but if they are well classified, they are
precious resources. It is good that in Japan plastics are collected by
type. If it could be directly connected to reuse, it would be much
better however. For instance, recycled plastics could be used for the
construction of an Ozeki septic tank, which will be mentioned later,
and last longer than a tank using iron plates. I would like to inspire
and encourage people in this field.
Population is an
issue. In finding how much land we need for a sustainable way of
living, we need to have a firm and global consensus. We have to decide
together how much land we need to live sustainably. This is one of the
most important projects. Shaking off the desire to need more and more,
we have to move to a place that enables sustainable living. For
instance, instead of looking for more copses for wood, we should
determine the amount to be used. Then we should stock this amount, feel
secure with it, and need not work harder.
like the Internet and email can transmit mutual information and
knowledge and we can elevate and uplift ourselves. Quite a number of
people have already visited my website not only from Japan but from all
over the world. Such spontaneous exchanges are very important.
It will not influence
anything, even if I do this.
often hear this kind of conversation. I want to warn them of what can
be found beyond this
doesn't affect anything.
If you are so
strict, you can not eat anything.
Somebody will do something,
it will be managed.
Recently things are
Many do this.
Motive to commence the project
project was not a sudden inspiration. My major field, Architectural
Acoustics, involves the control of Auditorium Acoustics to enable good
musical performances including suppressing uncomfortable noise. I was
involved in noise surveys and social questionnaires which resulted in
the suspension of landings and takeoffs after 9pm from Itami
International Airport. It is a pity that this airport is still active
after the Kansai International Airport was opened on an artificial
island. I worked to reduce the impact sound of aluminium baseball bats.
Through this work on noise control, I was also involved in air
pollution, water contamination etc. Further, when we performed the
synthesized evaluation of a room environment with noise, thermal
conditions and lighting, thermal conditions was the dominant measure on
the subjective scale of uncomfortableness, above the two other factors.
The quantified result explains clearly why we tend to open windows in
summer to get outside air even in a noisy environment. It also means we
can not avoid the issue of energy.
I planned to build either a
sustainable house for my lab in Okinawa right after it was returned
from the US or another proposal to a certain alumnus of the lab where I
was a student. However these plans were not realized. The following
reasons led me to decide to come to NZ: I had many good friends in NZ
through Acoustics; the land is not expensive; labour and construction
material costs are reasonable; it provides good opportunities for
students to engage in international mutual understanding. I brought
more than 30 students in total to NZ while I was on the staff at Kansai
University in Osaka. After 28 years work I resigned at the age of 60.
present education for Architecture focuses mainly on large sized
buildings which consume huge amounts of energy. Teachers who have never
even built a house teach Architecture - I was one of them.
Consequently, they don't know there are enough large sized buildings
and a saturation point has been reached, and they can't navigate in a
new direction. When I was invited to the preparation workshop of the
World Exposition at Hanover in 2000, I met an American Architect from a
well known Architect office, and he said that they don’t need
new buildings because they have already built enough for people in the
The thing that is urgently necessary in society
have space for practical work for sustainability and enable related
research to absorb young people who think seriously about their future.
As the present situation in Japan does not offer any such place, I
thought the project would be a good place to start. If a university is
a place only to teach and educate, the Internet can replace this.
However, we need places where we do research and have the consensus of
a university to contemplate all of human society. If large and
expensive equipment is obtained or constructed, free access should be
available for people to come with creation in mind. A large facility or
a plant with extremely advanced technology should be open to the public
with regard to how they are used. If it is occupied by capital, even
people there would be restrained. Free access will yield great creative
development, collecting each one's inspiration.
public nuisances have never been fundamentally solved. Minamata's
organic mercury, Yokkaichi’s smog, Morinaga's arsenic and so
still exist in a distorted form and people do not pay any attention
now. We don't feel anything for the eternal loss of the delicate and
fine beauty of rare species of plants and animals. Before we admire
them, they are gone and never come back. To which corner in the soul
world did we push them away? It is evident that we have done that.
Crows, sparrows, wasps and other unwelcome existences are widely
spread. Concrete buildings, factories that are only functional, ugly
things are dominant. Only ugly people are dominant and leading the
world. The world of feeling is made into a desert as well.
Experimental project at Kaiwaka (KW)
the above way of thinking in mind, we developed the following practical
goals for the sustainable project and have been trying to realize them:
To live using natural energy
(2) To build a house using
locally grown and/or existing materials
(3) To live without
producing any contamination from daily life
(4) To be
self-sufficient by organic farming, and
(5) To have a joyful
One by one, the present situation and plans for the near
future are presented in the following sections
1-1) Individual item for house planning
amount of solar energy that falls on the earth in a single year is
1.21x1017wat/hr. This corresponds to 15,000 times the energy that human
beings use in a year. If applied to Japan, the solar energy falling on
the land is 100 times the amount used by the entire population. If the
200 sea miles of surrounding ocean area is included, this goes up to
To give an example of the power of solar energy,
of the six main world deserts were to be covered by plants, and their
energy through photosynthesis exchanged with an efficiency rate of 5%,
the energy obtained would match the predicted energy needs of the world
in the year 2020. (Horigome Takashi:'Kagakuasahi' p.16, March, 1991)
this it is apparent that we can establish a sustainable lifestyle by
relying on solar energy. The following are the efforts done at the
experimental house to utilise solar energy in direct and/or indirect
Bio-gasification using the Ozeki septic tank
first item in this section is an Ozeki septic tank. Although the
produced amount of energy is not huge, it completely gasifies all
bodily waste as well as garbage. It makes sewerage infrastructure
unnecessary and also saves a lot of energy. I learnt of Hiroaki Ozeki,
the inventor of the septic tank, through a NHK TV programme on his
septic tank. I thought it had interesting possibilities for my project
and I firstly sent a few students to visit him. I visited him some time
later. He had a broad general knowledge and enjoyed those things he
felt meaningful for human life. Unfortunately, he passed away on the
third of March, 1999.
When I first listened to his explanation
how his tank worked, it was very persuasive. "Prof. Sakurai, think of
any degradable organic things, if you leave them outside, they vanish
in 125 days. So, the decomposition in my tank goes very slowly."
However, for so called academic societies qualitative expressions are
not accepted as papers to be published in their journals. Immediately
after I met him, we visited a local iron work at Warkworth and asked
them to make a smaller septic tank. Following his directions and
suggestions, the septic tank was able to produce bio-gas easily. I
persuaded him to publish a paper on the Ozeki septic tank to transfer
his knowledge. He accepted finally on the condition that I became a
co-author for the paper with his colleague. We chose 'Solar Energy' to
publish in. I visited his home several times and learnt more about the
tank directly from him, and wrote a manuscript with his checks and
corrections. Finally, it was published as the reference shown at the
end of this section. The ways to construct an Ozeki septic tank and how
to use it are presented in it. A booklet written in English has also
been printed - please see it or Chapter 5 for further information. In
this section, an abstracted explanation is given along with our
experience at the Kaiwaka Experimental House. In NZ, the surrounding
oceans are contaminated by fertilizer and animal waste and run-off. I
hope the following could be helpful in cleansing it. Bio-gas itself
accelerates the greenhouse effect, and it should be used for energy
while the burnt gas should be processed.
and F.Niwa; 'Biogas generated from organic waste in a septic tank',
Journal of the Japanese solar energy, vol.25, No.2, p53-60(1999) (in
An English written booklet is available NZ$20.
Contact Yoshi on email or with a letter.
discharge, organic waste, as well as animal manure are mostly
discharged through drains and pipes into rivers and the sea, after they
have been partially cleansed. Some is removed by trucks and burnt -this
consumes a great amount of energy producing carbon dioxide. The
discharge of waste into rivers and the sea supplies rich nutrients,
suppressing the natural self-cleansing process. This problem needs to
be urgently taken care of in conjunction with other environmental
For the protection of the environment, a sustainable
of living plays a vital role as it is in tune with nature's natural
cycle. Human activities must not be allowed to break that natural
balance. It is assumed that the energy used by human beings is 1/15,000
of the overall solar energy radiating onto the earth. This energy is
partly used for agriculture to grow food for human beings and animals,
and the waste should be taken care of in accordance with the natural
cycle thus inflicting no harm on the environment. In this section, the
septic tank for creating bio gas from any rottable organic waste is
The process of bio
gasification has two steps of fermentation. The first stage is acidic
fermentation, i.e. the liquefaction process. In it, complex organic
wastes are first broken down by the activity of facultative anaerobes
into soluble low molecular weight materials. Then they are decomposed
by the activity of obligate anaerobes into low fatty acid. In the
second stage, i.e. bio gasification process, the low fatty acid is
transformed by methanogen activity into methane and carbon dioxide etc.
These gases together are called bio gas. The reaction systems of
bacteria are shown and explained in Fig.1-1-1 with reference to the
digestion of food in the human body.
Fig.1-1-1 Ozeki septic tank
processes in comparison with human digestion.
has been widely believed that the temperature range for bacterial
activity is from 30 to 40 deg, and usually the liquid in a septic tank
has to be heated up to this temperature. In our septic tank, bio gas is
naturally produced in the low temperature range of 15 to 25 deg without
any heating. The septic tank is conveniently installed under ground
where it stays in that temperature range. We have heard that bio
gasification can work even when the outside air temperature drops to
Thus, the temperature range of methane bacteria
our septic tank is quite different from the range which has been
believed necessary before, we call them low temperature methane
bacteria. It is believed that the bacteria adjust themselves to the low
temperature in the septic tank. This finding eliminates the need for a
complex process to heat the liquid up and at the same time saves the
consumption of energy.
When we observe any organic waste left
nature, they are completely degraded in approx. 125 days. This does not
happen only in high temperatures. That means if waste is processed
artificially and unnaturally, for instance in specially raised
temperatures, the rest of their energy, which is degradable, will
remain as residue in the septic tank.
Requirements for bio gasification of large amounts of organic waste
the natural process of bio gasification mentioned above, a septic tank
for large amounts of organic waste was designed; its dimensions are
given in Chapter 5.
It is made of iron plates and the parts
exposed to air are of stainless steel plates. It is necessary that the
parts are carefully double welded together to avoid any leaks of air or
water. These dimensions apply to allow proper functioning of the bio
gasification process. They must not be made any larger for bigger
quantities of waste. If they exceed these limits, the waste can not
evenly ferment, especially at the rim. When a larger amount of waste is
processed, like waste from livestock, discharges at places where many
people gather and so on, an appropriate number of septic tanks should
be installed according to their capacity as mentioned further on.
outline of how to use the septic tank is given below:
Methane bacteria can be active only under
2) Place of installation
mentioned above, the septic tank uses natural fermentation with low
temperature methane bacteria, and must be installed under the ground
where it is sunny and not facing a strong cold wind in winter and where
underground water runs lower than it.
3) PH value
for the septic tank should be of a pH value of 7.2 to 7.6 which is
almost neutral or weak alkaline. If there is much urine, the pH value
rises to over 8 and it is important to adjust the pH by adding acid
producing materials, such as organic garbage, rice bran, maltose or
4) Natural stirring
The liquid surface rises
as bio gas
is produced in section (B), and when the bio gas is extracted, it
sinks. Then the liquid moves in the septic tank and is stirred
naturally. No artificial work is needed which is just like natural
movement in the human stomach and intestines.
5) Seeding and
preparation for the continual use of the tank
are very important and will be explained in detail later on and in
6) Material to be loaded
kind of organic material that rots, such as human discharge or those
from domestic and dairy animals, leftover food and organic garbage,
meat etc, can be bio gasified. However, the length of time and
efficiency of the bio gasification for each item varies, depending on
the rotting process.
7) Amount of organic waste
tank that ferments in the middle temperature range is loaded with 2 to
3 kg/m3 a day and for high temperature with 5 to 6 kg/m3 a day.
However, our septic tank has a natural fermenting process and can be
loaded with 1kg/m3 a day, maximum. The amount of loading per day is
given in Table 1-1-1, though this depends on the local climate.
Table 1-1-1 The amount of
loading per day.
Density of solids
The best density of solids in the septic
tank is at the ratio of 6 to 8% of the whole weight.
Duration of through-put
septic tank's capacity is about 70 to 80 times the usual daily input
including water. However, as it is designed to simulate the natural
rotting process, it stays a relatively long time in the tank; even in
summer it takes over a hundred days. The length of stay in each section
of the tank is shown in Table 1-1-2.
Table 1-1-2 Waste stay in
each section according to climate.
C) Production of bio gas
1) Components of bio gas and respective
is self-evident that the components and their respective quantities
change depending on the organic waste input. The overall results of the
gases are given in Table 1-1-3 called bio gas.
Table 1-1-3 Components in
biogas and their respective quantities.
sulphide, ammonium, indole and skatole are sources of bad odour.
However, these smells can be absorbed by de-sulphurisation material.
2) Amount of bio gas
amount of bio gas produced per kg of organic waste is 0.1 to 0.7m3.
Accordingly, the amount produced by the septic tank varies from 2 to
21m3 per day depending on the kind of waste. The flame temperature of
the burning bio gas is about 188°C. The calorie range is from
to 6,500kcal/m3, with an average of 6,000kcal/m３. For reference,
volumes of other gases that have the same energy as 1m３ methane gas are
shown in Table 1-1-4.
Table 1-1-4Volumes of other
gases that have the same energy as 1ｍ3 methane gas.
small septic tank that is installed at the Kaiwaka Experimental House
in New Zealand produces bio gas on average every day to boil one third
to a half cup of water per person's discharge and refuse. More precise
data will be available at a later point. A larger size tank has the
same digestive speed. From this we can say that the amount of energy
corresponds to less than 1% of the daily caloric intake by an adult,
and can be returned as a form of natural energy for each person.
D) Sludge, pathogenic fungi and parasites
1) Residue and sludge
mentioned earlier, if the septic tank is operated properly, almost all
organic waste is turned into bio gas, and there is no sludge-like
residue left, and no overflow.
Though the reasons are not
fully understood, the following are considered;
All organic waste naturally disintegrates within 125 days. After inputs
are entered into the septic tank with no forced artificial processing
like heating and stirring, bio gasification takes a long period of time
- over 100 days even for human discharge.
ii) The bio
gasification process is explained by an experimental formula as follows;
acid) (Water) (Acetic acid)(Carbon dioxide)(Methane)
+ CO2 + 2H2O --> 4CH3COOH + CH4
--> CH4 + CO2
the methane bacteria)
is also thought that the density and species of bacteria in the septic
tank are in a good equilibrium with each other as they are not forcibly
stirred. Thus, if there is a good balance between the groups of
micro-organisms which produces organic acid from complex organic
material and the one which ferments the organic acid to methane and
carbon dioxide it is thought that nothing will remain unprocessed in
the septic tank.
iii) As the dirt accompanied with animal
garbage accumulates in the tank, it should be eliminated at intervals -
probably only once every ten years.
2) Pathogenic fungi and parasites
are two ways to sterilize pathogenic fungi and parasites; one is to
boil them and another is to put them in anaerobic conditions. In order
to improve sterilization in the anaerobic septic tank, a barrier is
installed at the end of section (B).
In the inspection section
(C), the longest life span of each species was observed as shown in
their life span length is cross-referenced with the amount of time
spent in each septic tank section shown in Table 1-1-2, it is quite
evident that these pathogenic fungi and parasites do not come out of
the septic tank.
1-1-5 Longest life span
length in the septic tank for pathogenic fungus and parasites.
long as the septic tank has a steady fermentation process in winter, it
will shorten the life span in summer.
Fig.3 Another way to install the barrier to eliminate pathogenic fungus and parasites.
Seeding and fermenting for daily standard use
is critical to seed the tank prior to starting to use the septic
tank.Chapter 5 details the steps to do this – it is very
important to do this correctly.
First, the gas cock at the
the septic tank must be closed. 20 tons of human discharge which have
been kept in conventional toilet tanks should be introduced to the
septic tank. Water is added from the inspection manhole to the lower
dotted line in Fig.5-2-1 of chapter 5. The discharge from a flush
toilet must not be used as it is urea-decomposed and can not be bio
gasified. Secondly, fifty bagfuls of 15kg dry chicken manure should be
added through the entrance of the septic tank.
The gas first
produced is air which should be released until the pressure shows zero,
and then the cock should be re-closed. This procedure needs to be
repeated three times. If it produces fire after the fifth time, the
septic tank has been seeded successfully.
2) Preparation for daily standard loading
the seeding in 1), the system needs a gradual increase of organic waste
input to reach the stage of daily steady input. The situation can be
compared to the growth of a child's stomach to the one of an adult.
This process is different depending on the kind of loading material.
Now, the septic tank can accept the daily steady input in Table 1-1-1.
Although this preparation process is explained for each kind of organic
material in Chapter 5, the same amount of water as that of the organic
material should be added each time. However, in the case of human
discharge, containing urine as water, only half the proportion of water
is required. Therefore, careful consideration should be given to how
much liquid any input contains.
Thus, it is very important
start the bio-gasification with a small amount of waste and then
gradually increase it. When a steady amount of input is reached, the
daily input chart should be followed as indicated in Table 1-1-1. The
above given data is for seeding preparation in summer. For spring,
seven days should be added, for autumn, 15 days, and for winter 25
days. 12kpa of pressure should be maintained for the methane production
to be most efficient. When bio-gasification works normally the gas
should be used as it stimulates the remaining waste to move along the
bottom slope and ferment into bio gas.
A marine toilet should
used which flushes 280cc of water by pressing a foot step. Thus a few
pushes of the step for each use adds the proper amount of water. If a
water spray washing device is attached, the water running from this
device can be a replacement, and there would be less use of paper.
3) Deodorization of biogas
to eliminate sulphides which create a bad smell, such as hydrogen
sulphide, can be commercially purchased. The one at the Experimental
House can be used for 25 years in a cylinder connected to the septic
tank. To reuse the deodorant, it can be exposed to the outside for a
month on a mat and its black colour will return to the original brown
Small capacity septic tank for family discharge and refuse
dimensions for a small Ozeki septic tank for family use are shown in
parentheses in Fig.5-2-1, Chapter 5. The barrier to suppress pathogenic
fungi and parasites can be installed as shown in Fig. 3 of the recently
The seeding for this tank should also be
done very carefully, following these instructions;
Fill the septic tank with water to the lower dotted line in Fig.5-2-1,
Place 7 tons of old human discharge in the first section. As mentioned
before, discharge from standard flushing toilets must not be used; as
they are already urea decomposed and can not be methanized.
Add forty 15kg bags of dry chicken manure.
iv) Wait until the
above are bio gasified.
If human discharge can not
be obtained for step ii) 70 bags of 5kg of dry chicken manure can be
the Kaiwaka Experimental House, about 1.5tons of chicken manure
including urine, sourced from a chicken farm, was added to the septic
tank for step ii). Within a week, bio gas was produced and the pressure
reached 15kpa. After this only human discharge and organic waste were
used and the pressure gauge now stays at about 8kpa, because the daily
input is on average from just a single person. However, even this
supplies enough daily energy to boil one third to a half cupful of
water (More precise data will be given later). The liquid level in the
septic tank is kept just at the overflow level.
In daily use,
recommended ratio of human discharge to additional water is 2 : 1. Any
rottable organic material other than human discharge can be put into
the septic tank, as long as the ratio of solids to water is kept at 1
to 1. To produce methane gas CH4, one carbon needs four hydrogen atoms.
It is estimated that human discharge contains only two hydrogen atoms
and therefore another 2 must be added with additional water. The water
amount needed is less if organic refuse from the kitchen is added.
the Kaiwaka Experimental House, a marine flush toilet is installed that
releases 280cc of flushing water by pressing down a foot step. In order
to supply additional water instead of using large amounts of paper, a
water spraying washer is attached to the toilet seat.
maximum input for a day is 20kg of human discharge and 5kg of kitchen
refuse. A person produces about 1kg of discharge a day. If only 5kgs of
human discharge are put in, 20kg of refuse can be added. Green grass
can be put in as refuse, as it contains quite a large amount of water
when it is green. The important thing here is again not to exceed the
given limit that is mentioned above.
At the Kaiwaka
House, the bio gas produced is used for cooking. The gas flows from the
septic tank through a deodorant, via a pressure gauge and a regulator
to the gas burner in the kitchen as shown in Fig.1-1-2. A gas burner
for biogas use has not been specifically designed, i.e. one which can
be adjusted by a cock is used.
use of biogas for cooking at Kaiwaka Experimental House.
the beginning the toilet to the septic tank was connected by a plastic
pipe 2.6meters long, 20cm in diameter which ran under the shower room.
This meant that it was hanging under the basement ceiling. The reason
why it was horizontal was that if it was slanted, it would be clogged
up as it dried. If it is horizontal and has a drop at one end, it drops
to the septic tank in the other end. However, it was flushed after the
lid was covered and the reason why the toilet was dirty was not found
for a long time. The reason was the pressure produced in the horizontal
pipe and the first section meant part of the energy was lost. As a
result, the toilet was moved to be just above section A of the septic
tank. Even there the pipe from the toilet to the tank has to be slanted
and flushing is done carefully.
To solve the smell from the
toilet, the house plan is very important. It is recommended that a
toilet extends from the house allowing ventilation from the outside
air. It must be thermally well insulated especially for winter use. Its
floor needs to be at least 1m x 1.7m. The width of the tank is 1.5m and
the first section is only 50cm long. A few examples of toilet location
are shown in Fig.1-1-3.
Fig.1-1-3 Location examples
for a toilet and Ozeki septic tank.
important thing to note is that it should be dropped directly above
wherever the tank is installed. A chute should go straight to the tank
too. If a down pipe is slanted even for a short length as at the
Experimental House, sometimes it should be pushed down to the tank.
Both entrances in the tank must be as far apart as possible so as not
to cause interference. Bad smells does not occur much because of the
escape pipe which is connected between the toilet and the tank. As some
gas is produced in the first section, and the pressure is higher than
normal atmosphere, the outside air does not enter the first section and
the anaerobic condition there is kept.
If it becomes necessary
expand a pipe, it should be kept horizontal and less than 2.5m long,
and two bucketfuls of water must poured in once a week to keep it
liquid. The gas produced in the pipe is considered normal and an escape
pipe for it is a good idea. The quality of the gas should be tested
though. Once the gas pressure reduces to zero, it takes some time to
get back to the steady usual pressure. Especially in winter, it takes
longer time to recover.
The Ozeki Septic Tank at the
House is completely constructed by iron plates. A lot of rust is found
after 12 years where plates are exposed to air. It is a good idea to
replace such parts with stainless steel. To use new plastic for it
should be out of the question. If you limit use to recycled plastic, if
a tank is made with it, it should also last longer. Further improvement
will help to have a more comfortable toilet.
G) Other aspects to be considered
of the malfunctioning has been caused by overloading or when the water
ratio was not correct. As explained in Fig.1-1-1 the tank operates in a
similar way to the digestive process in the human stomach and
intestines, thus it must not be disturbed by using it improperly.
the bio gas is kept for a long time in the septic tank, nutrients for
the methane bacteria become low. Therefore it should be used constantly.
it uses acid fermentation, strong alkaline containing material, such as
soap water for cleaning the toilet and after washing, must be avoided.
not to be put into the septic tank are; stones, sand, plastic, rubber,
sawdust, rice grain, shells and so on.
would like to emphasize that the septic tank does not leave any
residues or sludge. This means that the pollution of rivers and the sea
with a lot of nutrients can be avoided, and the energy required to burn
human discharge and refuse can be saved and accordingly carbon dioxide
production can be eliminated.
The amount of energy produced
Ozeki septic tank from the waste of one person is not much: Enough to
boil just onethird to a half cupfuls of water per day per person,
depending on the season, however it is a sure way to get energy daily
from a human's eating habits. If more gas production is desired then
additional biomass should be added.
The bio gas is kept under
in the septic tank and is pushed out by its own pressure. There is very
little risk of explosion, even if a fire should occur above the septic
It would be meaningful to think and look at making the
tank from used plastic, because it lasts longer. However, to minimize
the environmental impact this should be strongly limited to reused
Human discharge from toilets in public transport
such as airports, bus and train stations, public meeting places,
restaurants, leftovers and refuse from restaurants, waste from stock
farms, and so on, all could be converted into energy.
starting point would be to install tanks at milking sheds and produce
electricity from them, and then New Zealand’s oceans would be
cleaner among other results.
The carbon dioxide from burning
can be channelled to growing plants whereby photosynthesis changes it
into oxygen in an enclosure such as a greenhouse. At the Kaiwaka
Experimental House site, we have a greenhouse for this purpose. An air
duct from the cooking range hood in the kitchen leads to the adjacent
greenhouse with three ponds where rice, azolla and other water plants
grow. The burnt gas falls over the grass in the ponds.
human activities do not inflict any extra load or harm to our precious
earth, and a sustainable system can be completed.
authors are grateful to Mr. Hideo Nogaki, former chief of pharmaceutics
at Japan Rail, for his measurements of the life spans of pathogenic
fungi and parasites in the septic tank. They also wish to appreciate
the help of Mr. Allan Neilson in publishing a booklet.
inventor's family will be happy to see the Ozeki tank produced for use
in protecting nature. If you intend to use the design to build a number
of these tanks for sale then please contact Yoshimasa Sakurai to
discuss a small royalty payment per unit for the inventor's family.
copies of the booklet contact:
House, 112 Gibbons Rd, R.D.2 Kaiwaka
Direct solar energy collection
mentioned before, the solar energy falls over the earth in huge
quantities. Without forgetting that it needs to be shared by all
creatures, if we collect it to use for our lives, it is very useful and
precious. The following is from a paper which was submitted to the
journal of the Japanese Solar Energy, with some parts being omitted and
a few comments added.
Y. Sakurai,"Solar Energy Collection-
the second report from Kaiwaka", Vol.22, No.1, p15-23(1996)
is difficult to rely on one kind of energy for maintaining a certain
standard of living a sustainable life, and it is better to collect as
many varieties of solar energy as possible. Temperatures at various
points of food cooking were measured, and how temperatures for cooking
could be obtained from solar energy and other practical experiments
were investigated. These include a solar oven, a solar cooker, a system
to get hot water, energy collection from sky radiation, energy
collection with porous materials, and so on.
(1)Temperature change during cooking
conducted four experiments investigating the temperature and the amount
of energy required for cooking and how this changes over time. Some
dishes were cooked and measurements taken. Using these results we could
determine what type of solar radiation collectors or biogas heat should
be used in different situations. The temperature was measured by
inserting thermocouples into foods or by measuring the surface
temperature. Measured points are shown in each sketch.
shows an experiment where a chicken leg (207g) was cooked in a gas oven
with dimensions of 30.5cm X 29.3cm X 18.5cm using low heat (160deg). It
took 50 minutes to cook satisfactorily. However, when the temperature
was raised to 230deg, it only took 15 minutes. A fan was used to
minimise the air convection layer to improve the heat transfer. It also
helped with temperature distribution.
change during grilling a chicken leg in a gas oven.
shows the temperature change when a steak (140g) was cooked in a frying
pan at a low temperature. It took 6 minutes to be cooked through. When
food requires a lot of heat to cook, the pot used in the solar cooker
should have some heat storage and a high surface temperature. A hundred
fifty degrees is sufficient to cook a steak.
change in a beef steak cooking on a frying pan.
change while cooking a stew in a saucepan.
shows the temperature change when a stew was cooked in a saucepan. The
stew was made with a potato, a carrot, an onion and chicken (200g), and
braised, then put into the saucepan. It took 30 minutes to cook and the
temperature rose to about 100deg. The dotted line shows the temperature
change when the saucepan was kept in the thermal insulation box. Three
croquettes were fried in 300cc of plant oil. The oil temperature was
around 200deg, as shown in Fig.1-1-7.
change when three croquettes were fried in 300 cc of plant oil.
food requiring a lot of heat to cook is put into a pan, the oil
temperature drops suddenly. It is important to use cooking devices that
are appropriate for the kind of food to be cooked.
equipment to improve efficiency.
(a) A thermal insulation box and skirt
soon as the food in a pot reached boiling point, the pot was removed
from the heat and placed into a thermal insulation box. In our Japanese
laboratory this box was made of polystyrene while in the Experimental
House a box insulated with wool fleece was used. After 30 minutes in
the box, rice or a stew was well cooked. The temperature change is
shown with dotted lines in Fig.1-1-8 for the pot during rice cooking
and for the stew in Fig.1-1-6 (in the previous section). This method
can be applied to some food which is boiled, in order to save energy.
Surrounding the pot with a metal skirt can also increase the
When the wind blows strongly, we
can cook Sukiyaki for four persons using an electric pan with the power
generated from the windmill. However, we can not expect that much
windmill power to always be available. Therefore a cooking range has
been designed to utilize a variety of energy sources in the kitchen.
(2) Direct solar energy collection for
equipment that can convert solar energy directly into heat is described
in this section. The experimental house uses a solar oven and a solar
cooker for cooking1) as well. Although their use is strongly affected
by prevailing weather conditions, they are great devices. When it is
fine, we are also able to produce enough heat to cook preserved food
and melt plastic to be reformed.
1) B & D Halacy;
"Cooking with the sun", Morning Sun Press, 1978.
i) Solar oven
mouth of the reflector aimed at the sun collects solar radiation that
goes through a glass plate cover to the oven at the bottom. The inside
surface of the oven is painted black and the walls are highly thermally
insulated. The inside of the reflector is coated with very highly
reflecting sheets on cardboard. At Kaiwaka, wool fleece is used as a
thermal insulator for the walls. The oven is shown in Fig.1-1-9.
Fig.1-1-9 Solar oven
aimed at the sun and its section.
calculated results (dotted line) can be compared with the measured ones
(continuous line) in Fig.1-1-10. The calculation used a reflection
coefficient of the reflecting surface at 0.7, the transmission
coefficient of a glass plate at 0.8, the radiation absorption of a
black surface at 0.8, the overall coefficient of heat transfer at
0.64kcal/m2hr C, and heat capacity at 0.352kcal/m2 C. Direct solar
radiation on the day of the experiment is also shown, there it changed
from 75 to 380kcal/m2hr. The measured result is lower than the
calculated one in the later stages because of air leaks.
of calculated and measured air temperatures in the solar oven.
(a) Measured direct
solar radiation on a partly cloudy day with a change 270-440kcal/m2hr
Measured direct solar radiation on a fine day with a change
the design phase the dimension of the mouth is one of the important
factors and it must meet certain geometrical conditions to utilise all
reflected light in the bottom box.
Temperature calculations in
the oven were made by using measured direct solar radiation from two
the area of the reflector's mouth was in the same position as for the
previously used reflector, the overall thermal coefficient K, the heat
capacity CAP and the oven volume V, were changed. The calculated
results are compared in Fig.1-1-11.
Temperature change when three parameters of the oven were changed.
bottom box is thermally insulated and has good heat storage. The heat
storage is for a sunny day with some clouds. A measured result is shown
Fig.1-1-12 Solar oven
on a sunny day with some clouds.
device to reduce heat loss is shown in Fig.1-1-13. When the cooking is
finished, taking the dish out allows the hot air to dissipate. If the
dish is moved into an adjacent compartment as shown in the figure,
acquired energy can be reused.
An interesting observation was
the temperature distribution in the bottom box was up to 40 degrees.
Therefore the cooking location in the box should be carefully chosen.
Fig.1-1-13 Less heat
loss at the change of cooking.
ii) Solar cooker
reflection of solar radiation on the parabolic surface is focused onto
the bottom of a pot as shown in Fig1-1-14. The reflector's mouth has
dimensions of 100.6cm x 100.6cm. The distance to the focus is 50cm. The
pot is made of aluminium and has a depth of 6.5cm, a diameter of 14cm
and a thickness of 0.5mm. The outside is painted black. There is a
heat-resistant glass case of 6mm thickness surrounding the pot with a
4cm air gap. The specially designed pot is placed between two parallel
iron angles supported by 12mm thick wooden plates. The total weight is
Thermal calculations were done by adding the
solar energy on the small segments on the pot. If each segment faces
the reflected light normally, it gets more energy.
cooker with a parabolic reflector.
our Lab in Japan we conducted an experiment with a similar cooker. On a
fine day the oil temperature was increased by 260deg. Frozen croquettes
were cooked thoroughly. The outside air temperature, direct solar
radiation, and temperature of the plant oil at that time are shown in
Fig.1-1-15. From this, it can be seen that it is not difficult to
produce temperatures high enough for frying.
Temperature change at cooking a croquette.
material with a large heat capacity, like a steak, is cooked, a pot
with its own heat capacity should be used. The thin pot was replaced
with one made of 3mm thick stainless steel. In this way it was possible
to produce enough heat to well-cook the steak.
winter, the sun from 10am to 2pm should be utilized.
(3)Other soler enargy collection
i) Solar energy collection by a two
this experiment, we covered a black stainless pipe (diameter: 2.5cm,
thickness: 1mm) with an acrylic transparent pipe. The air gap was about
4cm. The convection in the air gap was not taken into account in later
calculations. The opening of the parabolic reflecting surface was 100cm
by 100 cm, and the focal length was 20cm. We moved the reflector by
hand towards the sun and the water temperature easily reached boiling
point. The calculated result is compared with the measured one in
temperature change with a two dimensional reflector.
in Japan is characterised by fine, calm and humid weather. The solar
radiation collection with a two-dimensional reflector that tracks the
sun and generates electricity with a turbine would be ideal for this
and similar situations.
Six water containers of 2.8cm deep,
1m wide were made with galvanized iron plates and placed on the solar
room floor. The purposes were to store heat for lifting power before
the sun rises and to use the warmed water. However, they got only to
27deg at sunset in winter and this was not enough hot for shower water.
To increase the gain from the sun, a large two dimensional reflector
was installed to be focused on two cylindrical pipes of 18cm in
diameter in front. The first one was connected behind the last water
container as shown in Fig.1-1-17.
dimensional reflector to aim the sun at 30deg in the solar room.
stainless pipes were connected together by a copper pipe and the total
length was 4.8m. They were covered with transparent plastic sheets with
an air gap of 4cm. The reflector had a mouth area of 1.5m x 4.8m. The
temperature went up to 38deg on a winter day, when the surface film was
not peeled off. It was not enough hot to have a shower. We tried to
raise the header tank about a meter in order for the water containers
to face to the sun more directly. However we were not sure if the tower
could do this safely.
A circulation pump was going to be
to a hot water cylinder that was under the floor after the cylindrical
pipes. However there have been other priorities for the electricity
from the windmill. In addition, the battery effect from two different
kinds of metal started to ruin the water containers. This project has
been halted and the water containers are empty now. At present, two
solar panels are installed outside and used instead, as will be
mentioned later on.
Solar energy collection from sky radiation
we collect solar radiation, current methods tend to use direct
sunlight. However, it is important to know how much energy we can
obtain even when it is cloudy. To test this, an experiment was done
with a black hemisphere filled with water to find out how much the
temperature was raised. The hemisphere was covered with a transparent
plastic sheet with a 2cm air gap as shown in Fig.1-1-18.
radiation collection with a black hemisphere.
our calculations we used the measured sky radiation and the cloud
surface radiation was calculated backwards from this. The hemisphere
was divided into rings. The solid angle configuration factor of a ring
from the cloud surface was calculated and the sky radiation to the
hemisphere was obtained by summing up the radiation of the rings. The
reflection coefficient of the concrete ground was assumed at 0.1. The
water temperature when the hemisphere received direct solar radiation
only has been calculated as well. These calculated results are compared
with the measured results in Fig.1-1-19. This type of solar energy
collection gets more energy from the sky radiation. The water
temperature change on a winter day is shown in the following figure.
The dotted line shows the water temperature change only with direct
|(i) Water temperature
change in the hemisphere
Direct solar radiation and sky radiation on the experimental day
radiation collection with a black hemisphere.
shows the water temperature change in the hemisphere on a winter day.
The outside air temperature and the global solar radiation are also
temperature change in the hemisphere on a cloudy winter day.
iii) Solar energy collection using
results were found in an experiment measuring the temperature in cow
manure. The results showed high temperature retention of over 50deg, as
can be seen in figures of Chapter 5. Later on we did some additional
experiments on the roof top of a building with a variety of porous
materials. Each material was put in a double cardboard box, and covered
with a transparent plastic sheet. All the boxes were arranged in a line
in order to have the same exposure to the sun. One of the purposes was
to see if the high temperature in the cow manure was because of
fermentation or because of solar radiation absorption. The materials
used included wool fleece, stainless wool, horse manure, cow manure,
cut rice straw, fibre glass. The wool fleece, stainless wool and a few
others were painted black and put into different boxes. The
temperatures near the surface (4cm deep) and in the middle (12cm deep)
of each box were measured. A few results measured on a fine day and a
cloudy day, as well as the respective solar radiation, can be seen in
Figs 1-1-21 and 22.
the surface (4cm deep)
In the middle (12cm deep)
(iii) Solar radiation
on the day
Temperature changes near the surface and in the middle of porous
materials on a relatively fine day.
Near the surface (4cm deep)
||(ii) In the middle
||(iii) Solar radiation on the
Temperature changes near the surface and in the middle of porous
materials on a cloudy day.
material shows its own interesting behaviour and the following will be
i) The fermentation
heat of cow and horse manure produces high temperatures. However, this
phenomenon lasts for only one week.
The temperature near the surface of unpainted stainless wool was higher
than that of the black painted one.
Wool fleece has high solar radiation absorption and the temperature
change from the surface to the bottom was gradual.
measured the temperature distribution in stainless wool and wool fleece
in more detail. The measured temperature distribution in the stainless
wool is presented in Fig.1-1-23 along with the solar radiation. The
reasons why the stainless wool showed high solar energy absorption are
thought to be that the substance itself has high absorption, it is
thermally conductive and has heat storage, the mutual reflection
between fibres retains heat, and the air in between kept the heat by
not allowing air convection.
temperature distribution in stainless wool.
these results, we tried to warm water in a black pipe placed between a
stainless wool layer and a wool fleece layer. The measured result is
shown in Fig.1-1-24.
Temperature change in water in a pipe placed between stainless wool and
Summary of this section
the surface to absorb solar energy is covered with a transparent sheet
having an air gap of about 4cm, air convection is prevented and heat
can be stored well.
The details of the solar cooker are shown
Fig.1-1-14. The side wooden panels could be lighter if they had some
holes. If the reflective surface and the cover glass could be
mass-produced, it would be an inexpensive product. The best ways to
install it against the wind and material choice to make it as
nature-friendly as possible are important subjects to look at in the
future. It is worthwhile to introduce a skirt during cooking to use
energy more efficiently.
We would appreciate
reader’s proposals to develop any of these solar energy
Solar energy collection by solar panels
was planned to store the solar energy in water while it circulated by
means of an electrical circulation pump from the water tanks on the
floor of the solar room to a hot water cylinder under it. However, the
water tanks should have been slanted more to be more directed towards
the sun and so we thought to lift the header tank higher. However, I
thought that it was dangerous and that there was the possibility of
water leakage because of the connection of copper pipes and tin
containers, so the plan was abandoned.
Two solar panels were
installed by Don Slater (Solar Solutions) in Sept. 2002, after he was
introduced by a friend of mine on Gibbons rd, Lars Hakenberg Van
Goothbeak. This commercial system works by thermo-siphoning if a hot
water cylinder is higher than the solar panels, and it can be
The solar panels installed in front
of the shed are shown in Fig.1-1-25. Each panel is
Fig.1-1-25 Solar panel on
wide, 180cm long and 7.7cm deep. Eight copper pipes whose inside
diameter is 9mm run from bottom to top and are filled with water, each
pipe has a copper wing plate of 142mm width painted black. The panel
surface is covered by a sheet of glass. The rear of the panel is
When the panel is placed at an angle of
facing the sun, warmed water moves upward. A hot water cylinder, which
is inside the house and 1.5 meters higher than the panels, is connected
to the solar panels, gets the warm water, and returns cold water to the
bottom of the solar panels. The black wing plate over a pipe is the
heat exchanger. Beneath the pipes there is thermal insulation. In such
a way, water runs naturally from the solar panels to the hot water
cylinder being warmed up by the sun and as a result the solar energy is
stored in the water. This mechanism is called thermo-siphoning. The
planned system needed energy to lift water, but it is operated
First, a shed whose floor is 3m x 3.3m with a
about 4m, was constructed. Two solar panels were installed in front of
the Northern wall at 45deg facing almost directly towards the sun in
winter. In the shed, a fire place with a wet back has been placed as
shown in Fig 1-1-26. Hot water from the wet back is passed to the hot
water cylinder in the same way as the solar panels. It was used during
two winter seasons only on some cloudy days. In winter we
need toshower so frequently. The warm, sometimes hot, water is usually
used for showers, a washing machine and doing dishes. It is a very
efficient collection of solar energy and gives a large part of the
energy to the household.
Fig.1-1-26 A fire
place with a wetback in the shed.
key aspect of the system is thermo-siphoning. I want to simulate the
mechanism and investigate this further, for instance, how it can best
be directed for daily use or how freezing in cold areas can be avoided.
When the solar panels were installed the hot water cylinder was
connected to the header tank where cold water comes through a tap. At
the taps, hot water is equivalent to cold water because it is heated by
the free energy. I give appreciation to the sun for this.
the same system is applied to the solar room, the hot water can be used
for heating in winter. Namely, the natural circulation between a solar
panel and a hot water cylinder stores the solar energy in the day time
and the hot water can be circulated to a radiator in the living space
at night. The energy to be used by the circulation pump is just the
friction in between and needs not much electricity.
hot air near the ceiling of the solar room can be drawn through an air
duct to the basement ceiling just beneath the ground floor. The day
time heat will be stored in the walls. This is also thermo-siphoning
with air. It must not used below a certain air temperature, say 18deg.
By using the two systems, most of the solar energy falling into the
solar room can be available for our daily needs.
1-1-4) Fire wood growth (coppicing) and
woods have been widely used as fuel. They fix carbon-dioxide into
carbon through photosynthesis. When they are burnt directly or after
carbonisation, they release the same amount of carbon dioxide from the
air, and the proportion in the air does not change. They are also
convenient to store. In England they plan projects to use coppicing and
generate electricity by burning firewood, in the scale of the windmills
They grow trees which are active on photosynthesis and
them at 1.5m to 2m high when they become a certain thickness. New
shoots come out at the cut and from the root. They are cut and stored
for winter firewood. This is called coppicing in England. Here in NZ,
an experienced person instructed us on how trees should be coppiced,
depending on the tree species, growing time, the necessary amount,
plantation strategy etc.
At the Experimental House, seven
seven alders, five poplars, four willows were planted around 7 years
ago, and now they have grown to twenty meters or higher as shown in
growing coppicing trees.
acacias have already been cut to 1.8m above the ground, and new shoots
are expected. The new shoots will be dried and carbonised to be used as
charcoal. If the shoots are carbonised, they can be stored and burnt
inside the house without creating smoke. They can be a valuable cooking
fuel. Trees are composed of carbon, oxygen, hydrogen and trace
elements. During charcoal making, they are heated without oxygen and
the oxygen and hydrogen is removed. The temperature at carbonisation,
which occurs from ca 400 to 1,000deg, creates a different character.
They are selected by cooking. Charcoal is used not only for fuel, but
also absorption of smell, soil improvement etc. The brown liquid
by-produced at charcoal making can be used as an antiseptic. It is said
that 1000kg of charcoal is produced from the trees which grow on
1,000m2 of land. I give my trees 500m2 and get 500kg of charcoal. I can
use 1.4kg per a day. I want to find out practically how much charcoal I
will have at the Experimental House.
At this stage, biogas
for triggering charcoal and with the help of sheep and chickens, can be
used for cooking. I want to design a cooking range with four elements
to use the different sources, one with biogas, two with charcoal and
one with the electricity from the windmills. Recently, I attended a
meeting held by raw foodists. They eat about 85% of their food raw in
order not to kill enzymes through cooking. This is a good additional
way to save energy.
There are three
windmills. From the far end of the hill, a 1kw generator, a 300w one
and 400w one, respectively are installed. Long pine tree posts are
easily obtained in NZ so a post 10m long, 20cm in diameter was buried
deeper than a meter, fixed with concrete, and supported by wires
tensioned with turnbuckles in three directions. At the top of each
post, a corrugated iron pipe of three meters long and 10cm in diameter
was attached, then a windmill connected. The height of each post is 9m
on the ground. They are shown in Fig1-1-28 with the electrical
equipment and batteries. Generated
From the left 400w, 300w and 1kw generators
||(iii) Electrical corner
Electricity generation from three windmills.
is first rectified and used to charge four batteries of 6 volts
connected in series with a capacity of 350am.hr. Then, the direct
current of 24 volt is fed to the inverter through a controller
producing a 50Hz alternative current of 240 volt. When the batteries
are fully charged, the controller switches the excessive electricity to
a heating element in the hot water cylinder to protect the batteries.
As the alternative current has a modified rectangular form and high
harmonics, we would like to investigate how a direct current can be
used without an inverter or a low pass filter. Even so, it is possible
to produce enough electricity for lights and a small refrigerator. On a
windy day enough electricity is produced for washing and vacuum
An anemometer was set under the middle
it has now been moved around 7m away to the top of a different post ca
5m tall. The correlation between the wind data and efficiency of each
windmill will be interesting to analyse. And its data is used as
outside climatic information to predict indoor climate i.e. wind speed
and wind direction. The power company in our area called Northpower
once recommended windmills for remote farms. They offered periodical
checks too. One of our two 400w generators was broken because iron rust
broke the copper coil, and it was replaced by a 1kw generator by the
company. It is a pity that this section of the company has now been
The 1kw generator is quite sensitive to the wind. In
future the 400w generator will be replaced by at least a 1kw one. The
inverter uses a certain amount of electricity to operate.
domestic electrical system is operated with a direct electric current,
an inverter is unnecessary and the efficiency is better, though the
life of a motor reduces, the voltage can not be changed and any family
appliances must be changed to operated on direct current. Anyway this
is an important subject for investigation for sustainable living.
Roughly speaking, the attachment for a windmill is expensive. NZ$15,000
was spent for the total system of two 400w generators and a 300w
generator. However, if a social system of recycle and reuse is
established the technique can be refined. The 300w generator is
sensitive to breezes. It may be left to be available for emergencies
while the 400w one should be upgraded to a 1kw one.
batteries were used for 12 years but they then finished their useful
lives. They will be recycled by specialists. However, a capacitor made
of carbon and aluminium has been developed in Japan to store much
larger amounts of electricity with much fewer hazardous materials. It
is interesting to connect it to the grid too. A lighting bulb could be
replaced with an LED light which uses one or less watt. For a battery,
the development of a capacitor type is greatly anticipated, because it
would be much less hazardous and the natural discharge is small. In
general, it is windy in spring and autumn when the atmospheric pressure
If there is no wind but a lot of sunlight, it is
to use a Sterling engine which has a focus at the hot temperature side
with a reflector, and/or a bimetal whose movement can operate rotating
gears. Discussion on this is at the end of the section.
1-1-6) Ground heat use
heat storage of the earth should be really appreciated. The layer of
the earth 8m below the ground surface retains the average temperature
on the surface, given usual thermal conductivity. At Kaiwaka it changes
from approximately 0deg to 30deg with an average of 15deg. The
deviation of the annual temperature change in the ground follows the
exponential envelope depending on depth, and even at 3.2m deep, the
deviation from the annual average is only about ± 2deg.
Actually, the basement temperature only changes from 12.5 to 16.5deg.
We can use this fact to cool the house in summer and warm it in winter.
Pipes imbedded in the ground for this purpose are called cool tubes.
They are very useful for a climate which has a very hot summer and very
cold winter such as Japan, though we can not neglect the heat island
We have two sets of three cool tubes 3.2m below
surface which run 10m to the basement from different sides. There is a
solar room on top of the experimental house to obtain buoyant or
lifting power to get the basement air to the ground floor after the
heat is exchanged through the cool tubes. The solar room windows facing
outside are double glazed and the walls on the house side are thermally
insulated with 60cm of fleece. There is a chimney on the roof to lift
the air in the solar room which is sucked through four ventilation
holes in the floor and two in the wall. When it is very hot and the air
in the solar room is warmed, more cool air from the basement can be
brought into the house. See Figs. 1-1-29 and 30. For this thermal
technique, the house is constructed to have air tightness, thermal
insulation and heat storage. In particular, every opening has triple
glazing for later thermal experiment. At Kaiwaka, they are double
glazed at present as shown in Fig 1-1-31.
Three cool tubes vents and the solar room.
The outlet of a cool tube in the basement.
Openings with high air tightness and thermal insulation.
Hume concrete pipe with a 30cm inside diameter is used for the cool
tube. The concrete surface in the basement is also efficient in terms
of heat exchange. There is a wooden floor 80cm above the floor where
one third is open. The open side can be changed depending on the
dominant wind direction. Thus, the outside air comes through the cool
tubes and there is additional heat exchange with the concrete floor as
it comes through to the basement. The heat exchanged air in the
basement is lifted up by the buoyancy in the solar room through 12
ventilation holes of 10cm in diameter on the ground floor where there
is a living room, a kitchen, two bed rooms and other rooms. This
relationship can be described by a calculation linking three equations,
firstly Bernoulli's describing air flow, secondly that of thermal
transfer, and thirdly that of heat balance in a room. They are shown in
Temperature changes in the northern
bedroom in July
1996 and in February 1997 are shown in Fig.1-1-32, where a continuous
thick line shows the measured temperature, a red line the calculated
result, and a thin continuous line the outside temperature. If the
daily average outside temperature is compared with the inside
temperature it is obvious that the ground heat affects the indoor
climate. The calculation was done by one of my students Dr. Hirotaka
Azumi. More details are given in Chapter 2. The gained heat, in
negative numbers, through the cool tubes on the hottest day and the
days before and after is shown in Fig 1-1-33.
Air-conditioning in the northern bed room using ground heat.
Fig.1-1-33 Heat gain
from the ground through the cool tubes.
change on the hottest day and the days before and after.
(b)Heat gain on these three days
this system, the temperature in the basement is 16.5deg in summer and
felt as uncomfortable as an air-conditioner in an office. If one stays
there for long, it is necessary to make adjustments with a thick cloth.
The air there is always fresh and not the same as that produced by an
air-conditioner and all that needs care is the temperature. However,
more research should be done on the health implications.
point is the leaking rain water from the joints of the cool tubes. They
are caught with rain drainpipes at the exit of each cool tube and
collected at a corner of the floor. Fortunately the house is on a hill
and there is drainage to the creek in front. Rain in winter means a lot
is collected but the relative humidity doesn't rise very high. A metal
layer 40cm thick surrounds the outside of the concrete block basement
walls;a perforated drain pipe 10cm in diameter has been placed at the
bottom which funnels all the rain water to a corner. The purpose of the
system is for the basement not to be lifted by rain water buoyancy. The
rain water which leaks through the cool tubes is removed via the
outside drain pipe.
Plans for the near future, experiments, and challenges
cooking range will be placed in a corner in the kitchen. It has two
charcoal ranges, a biogas range and an electricity range. The main
cooking range use charcoal, but when I look back on my childhood fire
triggering with this kind of range was very difficult. Thus biogas will
be used for this purpose. This is an urgent project as is charcoal
making. A sketch is given in Fig.1-1-34.
Fig.1-1-34 A cooking range
using a variety of energy sources.
Upgrading of the windmills
has been proven that three windmills are useful. They give us a certain
useful amount of energy with the atmospheric pressure change in spring
and autumn or during unstable times in winter. The 400w generator will
be replaced to one of the same type as the 1kw generator.
Electricity generation by a Sterling
wind does not blow strongly in the Japanese summer, but the sun is
strong. Electrical generation by temperature difference can be
utilised. A Sterling engine is an external-combustion one and has high
and low temperature sides. Both are connected through air and generate
a piston movement if the hot side is heated. The movement can be
transformed to rotation with two driving wheels. It was invented in the
early 19th century in Scotland. Its model is shown in Fig.1-1-35.
Fig.1-1-35 A model of
energy can be focused on the hot side with a reflector or a Fresnel
lens. The cold side can be exposed to the surrounding air. The rotation
of the driving wheel is used for electricity generation. Tracking the
sun is done on a rotation table, with the time and location of the
place obtained from a calculation with a small computer, whose
electricity is obtained from the engine. The resultant electricity will
charge the batteries for the windmills.
Electrical generation by a bimetal
deformation of a bimetal that is proportional to temperature can be
collected as shown in the following sketch Fig.1-1-36. The back and
forth movement can be transformed to the rotation of an attached gear.
It will be changed to a faster one with a few gears and be set in a
thermal insulation box which faces the sun. The temperature there is
expected to be more than 250 deg.
Fig.1-1-36 A sketch of
electricity production with bimetals.
Heating system with solar energy gained
from the solar room
have seen that the thermo-siphon is useful to store solar energy. By
having the system in the solar room and storing the day time solar
energy in the hot water cylinder, we can send the heat to a radiator on
the ground floor for cold winter nights. I hope the trusses are strong
enough to support them. Having a solar panel on the deck and a hot
water cylinder in the attic, the height difference between them
decreases and the energy needed for a pump to rotate the water is less.
solar energy other than that falls over the solar panels warms up the
air there. As it composes the vertical temperature distribution, we can
expect quite high temperatures near the ceiling. An air duct intake is
placed there and the hot air is sent to the distribution air duct under
the basement ceiling. The air moves up to the living space and comes
back to the solar room, while the heat is stored in the house. This is
thermo-siphoning through air. With the two improvements winter should
The formulation will be given in Chapter 2 or 5. If
system is solved and connected with the indoor thermal behaviour, we
can improve the usage of thermo-siphoning.
A sleeping chamber in the basement
annual temperature change in the basement is from 12.5 to 16 deg while
a human being produces 100 to 150w. If a small thermal insulated
chamber is assembled, it could be turned into a bedroom. We must not
forget to at least have air ventilation holes. Thermal-insulation walls
can be done with wine cask boxes filled with dry grass and connected
with rice straw.
with solar energy absorption by porous materials
solar energy absorption of stainless wool is unexpectedly large as was
mentioned in the section about direct solar radiation collection. Black
pipes are placed not too deeply in the layer and the inside water is
connected to a hot water cylinder and stores solar energy as shown in
Fig.1-1-37 Solar energy store
with the solar panel using stainless wool.
heat can be used during the winter night
too. The system must be sufficiently thermally insulated and the front
glass pane adequately resistive against high temperatures. If it tracks
the sun, maybe manually, much more heat will be obtained. The negative
radiation in the night is large on a fine winter day and should be
avoided by covering. The systems would supplement each other. Except
for the heat exchange part this has the same mechanism as the solar
generation with the temperature difference in the house
may be possible to use the temperature difference in the house to
produce electricity using the heat pump and turbine principle.
Temperatures are from 12deg in the basement to 30deg in the solar room
in winter and from 16deg to 50deg in summer.
Outside bath heated by burning Kikuyu
that was brought in from Africa has very active photosynthesis. A book
says that its efficiency of photosynthesis is 8.1% compared to 4.7 to
4.8% for all other grasses, and kikuyu easily covers half of the North
Island. It was imported about 50 years ago and from this we can imagine
how energetic it is. If nothing is done, the North Island could be
covered with this grass and the land could not be used for other than
stock farming. We quite like the idea of changing a disadvantage to an
advantage by finding a good use for kikuyu – for example it
be used as fuel. While not an urgent project it would be interesting to
build a shed for a bath on the slope, where Kikuyu could be burnt to
top up the water temperature warmed by solar energy. It will be called
Kiku (chrysanthemum) yu (bath) from the sound of the grass. It will be
nice to feel relaxed, review the day and think of tomorrow. We must
however consider how much additional energy is needed to harvest the
A variety of items for solar energy use were
mentioned in the details for house design. They are classified as
※ Direct collection of solar energy
2 Solar cooker
3 Collection by the two
dimensional (cylindrical) reflector
4 Energy collection of
the sky radiation
5 Porous material uses for solar energy
6 Hot water by solar panels
generation by a Sterling engine
※ Solar energy
collection through plants
8 Coppicing for firewood and charcoal
Methane generations by the Ozeki septic tank
10 Solar energy
and Kikuyu burning for bathing
※ Energy collection
through natural phenomena
11 Windmills electricity generation
Ground heat use
cooking, mainly items 1, 2, 8 and 11 (only during strong winds) will be
used. Coppicing (8) is especially handy for energy storage. 9 will be
used for triggering charcoal, but can be used for cooking with the
contribution of animals, e.g., chickens and sheep. It saves a lot of
energy to have raw food meals and this also does not kill the enzymes
in the food.
Hot water from the solar panel 1.8m x 2.4m wide
enough to enable a person to have showers, do dishes and washing
through almost the whole year. If dead trees, fallen leaves, Kikuyu etc
are burnt ina fire place with a wetback, the double area of the solar
panels is enough to supply hot water for a four member family.
3 and 7 are used successfully, their electricity can be added to the
batteries. The top priority of the electricity is for a PC in order to
have communication. A small refrigerator and lights can be used too.
While quite an amount of food can be stored in the basement and crops
can stay in the garden as long as possible, a small refrigerator is
For heating the house, 6 and 12 are necessary.
use of the solar energy obtained in the solar room should be circulated
using thermo-siphoning through water and air as mentioned before. The
inside eastern wall will be cobbed to allow less heat loss in winter
after checking by calculation. Item 10 is for relaxation and is not a
In such a way, we need to see solar
energy from a
broader angle and viewpoint. Then, grasping the seasonal change of each
obtainable energy source and knowing the total amount through the year,
we should plan our practical energy use pattern with reference to this.
We have to properly align solar energy with daily demand, and if it is
not enough, use other possible energy types available at the time to
cover the shortage. For that purpose, we need to store each energy
type. Batteries, a gas container, heat storage in water and/or walls,
storage in the ground, a tank for rain water, firewood and charcoal
etc, all are delay systems, and should be well planned and applied.
1-2) House designing and planning
most important starting point for living sustainably is to observe and
learn at the site: landform, geology, the climate through a year (wind
direction and velocity, fine, cloudy and rainy days, water level change
etc). Then after researching the site conditions, careful consideration
should be made on how each detail shown in 1-1) should be used in a
house design and plan. Thermal conditions and planning with the sun in
mind should be the very first priority. Here we just point out that it
is very important to start with this in the planning stages and the
main strategy for thermal conditioning will be developed in Chapter 2.
a house is thought of as one system, thermal conditions are solvable by
linking two equations for heat balance and air movement with the one
for thermal transfer through the enclosure. Using this technique, a
comfortable thermal condition plan can be realized in the house after
taking into account the house direction, the design of eaves, the
dimensions of doors and windows, thermal treatments at the boundaries
and so on. This is the most active use of the sun. A computer program
to do this was made by one of my students, Dr. Hirotaka Azumi (a
temporary lecturer at Sohai College in Osaka). In a comparison between
the measured results and the calculated results given earlier, the
calculated one follows the measured one quite well, having a largest
discrepancy of 1.5 degrees which is explainable by human disturbances.
The program is ready for practical use and more details are given in
Furthermore, environmental planning is also
create a comfortable indoor climate. The synthesized evaluation for
this will also be provided in Chapter 2.
(2) House construction with local
place in the world has their own locally developed and specific ways
for housing and living. These are the results of their
creations from long past experience and communication with nature. You
could say they are a gift from nature. Before mass production was
introduced, these ways were passed from generation to generation. From
here on we will call this 'vernacular'.
There are so many
of this in Japan. Rice paddies in curving terraces are a great
infrastructure which was obtained after many years trial and error,
learning from the direction of the sun, the wind direction in different
seasons, water supply and drainage and so on. Crops are of course for
food and stalks can be used for a rice straw rope, a pair of grass
sandals, 'susa' binding in a clay wall, a sweeper, even thatching and
so on. 'Shoji' and 'fusuma' sliding doors are elaborate works from our
ancestors. They are the reflection of our old saying, "A house should
be built thinking of the summer climate".
It is a great pity
many of these things are fading. We have to look back once again and
connect old treasures to a sustainable life with scientific
Thatched houses are widely
seen throughout the world and are a typically vernacular form of
construction. A variety of materials are used such as local grass, crop
by-products, even seaweed. For the purpose of thatching, grass must be
hollow with a strong straw wall, for instance 'susuki'(zebra grass),
water reed, rice straw, wheat straw, tall fescue etc. Ways of thatching
are basically similar, but differ depending on local conditions such as
rainfall, snowfall, how the wind blows or local topography. They
thatched learning and talking to nature. If birds come, flowers bloom,
or moss grows on the thatched roof, this depends on the thatching
material, the local climate, the slope of the roof etc.
refined craft is fading in the strong wave of industrialization and it
breathes very feebly. In addition, thatching material is difficult to
procure. The common spaces to grow 'susuki' in Japanese villages are
vanishing and their storages for years to thatch or renovate a roof are
fewer and fewer. This sort of thing is an important subject to do
further research on to support a sustainable way of living.
2-1-1) Thatching process
thatching is stitched in and out and tied down over a purlin from the
bottom to the top as shown in Fig.1-2-1. At the experimental house, it
was done over the plywood roof and our German thatcher, Norbert
Kleinschmidt in Nelson, had a hard time. A few photo snaps of his
thatching are shown in Fig.1-2-2.
Fig.1-2-1 Basic method for
Fig.1-2-2 A few photo
snaps of thatching.
2-1-2) Maintenance of the thatched roof
following is an extract from my diary. When Norbert first came to do
renovations was three years after he thatched the roof. He could not
spend much time and it was not a large renovation.
possums and birds damaged the roof and I did a bit of mending, but I
could not do much because I could not get materials. Seven years after
his thatching, he came over for the first major renovation. We went out
to get thatching material in the form of bulrushes before he came.
Through the local paper (“The Bugle”) we placed
asking where we could get the grass. We got a few responses and went to
two of them to collect bulrush with a few helpers. For me this was the
first time to collect it directly myself. It was unexpectedly hard
work. I could not keep working over the space of a week. Thatching is a
wonderful trade but it is hard work to collect just the base material.
The cut bulrush was dried in the greenhouse and thought to be enough of
an amount for the renovation. But Norbert needed all we had collected
just for the lower half of the renovation. In the meantime, I had
informed the local newspaper that he would perform and also explain the
renovation. We got about 15 people to a meeting and they were quite
interested in what we were doing.
We discussed the second
the roof and decided to change it to a shingled roof because of the
shortage of bulrush. Norbert came back and started to remove the thatch
from the upper part, selecting good sections for later use on the lower
slope. The top of the bulrush was damaged to about 5cm, but the rest
was fresh enough to be reused. I cut the top with a special cutter, and
the fresh parts were bundled and kept in the greenhouse, later they
were moved to the attic.
There are two ways to
renovate. If a
hole is large and there is space under the wire to tie down, long
bulrushes can be inserted tightly. If a hole is small and bulrushes
still remain under the wire, short bulrushes which are cut to the
proper length are hit into them with a wooden plate hammer. In other
words, the additional length is inserted into the remaining bulrushes.
If they are tight and wide, the inserted additional length must be tied
down too. In the middle of a long wire, a wood screw is tied. The
length of the double wires is the thickness of a thatch. It is screwed
on the purlin. A half split bamboo is tied down over the additional
thatch with the wires.
A bird net was put up in February 2002.
many people noticed it even at a close distance, and birds look like
they have given up nesting in the thatch at least. Norbert left me a
chair to be stuck in the thatch, under which there are two pins of a
thin iron plate, and a tapping hammer of a wooden plate as shown in
Fig.1-2-3. In the figure, the set of his tools for thatching are shown
as well. Good material which is hollow and has a strong wall is
necessary. Water reed is such a material, but it is considered noxious
thatching tools in the left and a few tools for mending.
possibility is if rice straw grows well and long and another is
to use long wheat straw. Recently, I was told that there is a native
grass called Kuta which grows two meters tall like a water reed in a
lake. I want to go and see it.
2-1-3) Thatched houses in the world
village is well known not only in Japan but in the world as a global
heritage area. There a wonderful collection of thatched houses at
Hattori-ryokuchi ethnic museum. Some photos from my collection are
shown in Fig.1-2-4.
houses in the world.
2-2）Rain water for daily household use
is no concern about acid rain in NZ as of now. Rainwater is drunk in
remote areas. Our ground rain water tank is made of reinforced concrete
with a height of ca.2m, ca.2.5m in diameter and a capacity of 15,000
litres. Inside the tank, no light comes in, and germs do not grow so it
is clean. Fig.1-2-5 shows the present water supply system from the
ground tank to the house. We drink the water once boiled, but if we
could find a suitable filter to kill bacteria and viruses, we could
save that energy. We have to study the sterilization effect of bamboo
charcoal. A hand or foot pump will be used to lift the water to the
header tank. The overflow at the top of the ground rain water tank
discharges the floating organic mix. If we have a U-shaped pipe to see
the inside water level, it would be handy.
Fig.1-2-5 Rain water supply
the entrance to the water tank, a sludge trap is connected as shown in
Fig.1-2-6 Sludge trap
to eliminate large rubbish like tree leaves.
rain water from the spouts includes tree leaves and other rubbish,
first they drop into the big cylinder where a ball floats, and rubbish
is stopped by the floating ball. Then only the clear part above the
ball goes into the water tank. These days we drink the water directly
from the tap – we carefully observe the quality and there has
been no problem fortunately. I will pump up the necessary water for
daily use to the header tank, but at this stage I rely on electrical
Japanese clay walls are typically
vernacular. I gave a talk at a small international conference held at
the Dept of Architecture, Auckland University and needed to learn about
it quickly. Here the manuscript 'Vernacular aspects of Japanese clay
walls' is reprinted.
This report looks back at the history of
Japanese clay walls especially from the vernacular point of view and
how the technique developed by the climate and culture can be
applicable in the present day and harmonizing with nature. It has been
said that a Japanese house must be designed and built for summer. The
Japanese summer is very hot and humid; the environment must be thought
of more than any other factor. Accordingly, air flow is very important
to decrease discomfort as is the intercept of the sun by deep eaves.In
the past, a house structure was mainly of timber frames and a wall was
only a partition or a curtain wall. In other words, the frames
supported the entire load. While many Western walls had a role in
supporting loads, Japanese ones were not counted on to give this
support. However, one thing that we must not forget is that Japan gets
a lot of earthquakes. For that reason a komai mesh in the clay wall is
An old example 1300 years ago is found in the
temple's clay wall. As the base of plastering, a lath called 'komai'
was woven. In olden times, the lath was knitted with thin wooden
blanches or split branches and stitched with rice straw ropes. Over the
lath, earth or clay mixture with cut grass 'susa' was plastered as a
first coat. The 'susa' was used to link dry cracked clay pieces. Rice
straw, hemp or paper etc was used for 'susa'. For rendering or the
first coat, very clayish earth was mixed with 'susa' of rice straws
15cm long. Less clayish earth was sieved and used for the middle coat.
The next coat was created with 'susa' of rice straws ca 3cm long. The
finishing coat was white earth or slaked lime in the Heian era (8th to
12th cent), and later, slaked lime finish was applied to make the white
surfaces of castles and mud-walled storehouses.
to be used for 'komai' in the middle of the Heian era. Bamboo 'komai'
were used in most of the clay walls in the Momoyama era (16th cent).
'komai' has a basic role to prevent cracks and to be clung to by dry
clay, but it has to be noted that it worked to hold the wall against
earthquakes as well. The plaster trade was established in the Momoyama
era, but its origin went back to the Nara era (8th cent). The technique
to mix paper into slaked lime was a unique Japanese way. Slaked lime,
Ca (OH) 2 was obtained from calcium oxide, CaO by mixing water.
castle walls had to be solid and fire-resistant against enemy attacks,
they needed to be finished to be thick enough to do this. Walls of the
Himeji castle were plastered 49cm thick.
Its structure is
basically the same as in Fig.1-2-8, there 'komai' provided the
essential groundwork too. The first coat plastering was given over to
'komai' and to get a good assimilation of later plaster, rice straw
ropes of 30cm were hung. Clay balls mixed with 'susa' were twisted into
them by hand making a thick wall foundation. At the Hikone castle,
'komai' were doubled and pebbles were filled in between, then the rear
side of 'komai' could not be plastered by hand. As the surface of a
horizontal plane had to be plastered upwards, bamboo sticks rolled with
rice straw ropes were nailed to the plane to create a good bond with
the first coat. Its thickness naturally became thinner. Then the middle
coat was done and finished with slaked lime. In such a way, the whole
surface of the Himeji castle was plastered in white and it is called
the White Heron castle.
Fig.1-2-7 Clay wall
of the Himeji castle.
the beginning slaked lime was mixed with rice porridge, but rice was a
precious food and an alternative was needed. Ground shells were also
used together with slaked lime. A seaweed (Gloioperitis) was boiled and
used as glue. The glue of the seaweed was used with the slaked lime
too, and it was used for the coating of common houses since around
1600. Before then seaweed was only a food so it could be said that this
was a technical innovation. It is said that oil was mixed in to improve
workability. The glue improved adhesion and held moisture. Also it made
the mixture stickier and improved workability. This technique was
applied to a mud-storehouse. The main house was built with wood and
burnt easily. A solid store house was needed. There they applied the
same technique as for the thick wall construction of a castle.
constructing 25 castles around 1609, many plasterers lost their jobs
and moved to work onbuildings and mud-storehouses using seaweed glue
and a lime of ground roasted shells, because they could not use the
rice glue due to the extravagance prohibition law that was in effect.
was made as small as possible and the then skilled plastering made
strong doors and windows which were multi-layered and air tight. During
World War II, houses mortared on the lath and wooden houses were
completely burnt down by bombing, but mud-storehouses remained here and
Such structures have great heat storage and are
against solar radiation. They can be used for indoor environment
control depending on the local climate. If 'komai' is doubled with an
air gap in between and plastered from both sides, it lessens the heat
The partition of a thin wall started to use
bamboo for a
'komai' net and had structural stiffness. A tea ceremony room was build
very modestly using a tree as it was for columns and clay walls. 'susa'
was shown on the finish to make the texture enjoyable and create a
modest expression. And 'komai' was partly left open as a window.
Unfortunately, the modest expression turned to an ornate one later on.
In the Edo era (17th to 19th cent), there was legislation against
luxury and extravagance, and there was an influence to create beauty in
modestness. It seems that politics some times affects even construction
It is just a partition but it occupies a large area
house. It was necessary to be artistic and using a variety of earth,
the most sophisticated skills were shown in the plastering technique.
Katsura-rikyu Palace left a wonderful creation as a German Architect
Bruno Taut noted. The plastered surface was finished with slaked lime
mixed with paper fibre 'susa', and afterwards its surface was
scratched, in a way called 'parari' and with a coarse but fine finish.
This technique has disappeared. The climate and the local building
materials created different constructions in Edo (present Tokyo) and
Kyoto. This is the exquisiteness and charm of vernacular methods.
Cobbing (plastering) process at the
the excavation for the basement, the soil was left for cobbing from
three layers of soil. David Studholme and Ron Hutt from Waimate in
South Island tested the soil to determine which layer of soil was the
best for cobbing. Cobbing was done over the 2x4 structure from both
sides. Our traditional 'komai' lath was knitted with split bamboo, but
we found that it took so much time that it was decided to knit only the
eastern inside wall. Actually two of my students did this and it took a
good month for the area of 8m x 9m to be completed. The other area was
made with stapled wooden battens. The first coat was expected to be
done in the Japanese way, with the mixture of clay and 'susa'. During
discussions sand was already mixed. The first coat needed quite a
period to dry but it turned out to be impossible to do this for further
layers. The later two layers had cement mixed in. As a result the
cobbing was not done with a consensus which was my mistake.
basis of Japanese cobbing is firstly a 'komai' lath, which is knitted
split bamboos and stitched with rice straw ropes, and secondly, to cob
layers over the keys of cracks. 'komai's bending strength works well
against earthquakes and 'susa' is clung to by the clay to hold the wall
when it is dry. The first coat adds the mix of clay and 'susa' and one
waits until it is dry (see Fig.1-2-8). The clay becomes hard and gets a
lot of cracks, but the 'susa' holds each other. On the rear side of
'komai' a lot of keys come out and the surface of the first coat gets a
lot of cracks. These are the keys for the second coat. This is mixed
with sand and the surface cracks become finer. These are the keys for
the next coat. The finishing coat is the mixture of clay, fine fibre,
sand and seaweed glue (or rice glue).
finishing coat is
mixed with cement, the clay part wants to get rid of water and the
cement part wants to get water and crystallize with it. They should be
slowly and carefully dried, otherwise the surface will get cracks. At
Kaiwaka, because it was plastered over the 2 x 4 structure, a large air
gap was created to be used for thermal insulation. A variety of
materials were used as fillings. Wadded news paper, wadded plastic,
bulrush, fibreglass, and fleece were filled in the air gap to compare
the thermal behaviour there with the wall of air only. The heat flow
and thermal conductivity coefficient there will be measured. The
windows and doors are triple glazed in different styles. Later, the
heat flow for each style will be measured. When the thermal
conductivity of bulrushes filled in a 12cm width of the 2 x 4 wall is
estimated at 0.063, the overall coefficient of heat transfer is 0.43
which compares equivalently with that of a commercial modern wall. It
tells us that with a traditional cobbed structure thermal comfort can
Fig.1-2-8 Plastering a clay
wall with 'komai' lath.
the second coat over the first one.
Finishing coat with
mixture of rice gruel at the dark section.
shown in Fig.1-2-9 first and second coats were tried, but unfortunately
we could not finish the discussion and reach consensus. Recently, we
have a bad influence upon the Eastern and Western walls. Japanese
cobbing uses the hardness of dry clay like concrete, but in NZ they mix
a bit of cement in and clay must include sand. When the original
selection was made I believe sandy clay was chosen because of that. In
terms of nature-friendliness, an adobe structure is wonderful and
widely built throughout the world. However, lack of earthquake
resistance is a point against it. Bamboo tends to be forgotten as a
building material. It can be used to reinforce clay structures. It can
be bent while it grows. Its round shape can be squared if forced by
four panels and the square bamboo can then be a beam.
looked for a seaweed gloioperitis which is used as glue for the
Japanese clay wall, but we could not find it in NZ. This felt strange,
because the ocean between NZ and Japan is connected. Indeed, some
familiar Japanese fish can not be found in NZ and NZ has a lot of fish
which we don't have in Japan. Even though the ocean is connected, apart
from migratory fish, fish species are local after all.
conclusion I believe that traditional Japanese clay construction is
very suitable for NZ which experiences similar earthquakes. Going
forward I want to redo the walls in the Japanese way to create a good
(3) Cleansing of exhausts and drained
water from daily activity.
best prevention of environmental pollution is to do it at the source,
nothing else is possible. If a pollutant is known its processing is
easily found. On the other hand, if processing is tried after things
are mixed, it may be necessary to choose an easy way, such as burning,
which produces secondary contamination. The pollution from a family
house must be done following the principle of cleaning it at the
source. Human activity must not contaminate the outside environment.
The pollutants created by human activity are excretions, soapy water
from a shower and doing dishes, carbon dioxide by cooking and heating
etc. If all pollutants are processed well and returned to nature, human
activity does not cause any harm to the earth and its living system is
gasification of organic wastes
septic tank is a wonderful invention as was explained in 1-1-1). It
processes at the source excretions, garbage etc to biogas, and a large
infrastructure such as a sewage system is not necessary. It does not
need any energy to warm the liquid. Consequently, the energy that is
used to burn excretions is not needed. This is just an ideal system
where natural processing is applied. In NZ, cow manure at milking is
spread with water and reaches a creek and then is carried to the ocean.
A place where many people gather, such as an airport, produces a lot of
garbage and excretion during a flight. Auckland airport gets 7 tons of
this refuse a day which is burnt at the corner - I hope that Ozeki
septic tanks could be used there. The biogas turns to carbon dioxide
when it is burnt. Its processing is described in the following section.
3-2) Cleansing of drained water and
carbon dioxide in the green house
the area next to the Experimental House, there is a greenhouse that is
4.5m wide and 10m long. It has an agitation pond and three cleansing
ponds, with an air duct from the kitchen. It sends the burnt gas in the
kitchen with an electric fan over the plants in the greenhouse, cooling
it down on the way. Photosynthesis by the plants analyses and absorbs
the ingredients of grey water and change carbon dioxide into oxygen.
Please refer to the early stage plan and results in "Nature-friendly
experimental house - Third report from Kaiwaka - Clarification of
carbon dioxide after cooking and drained water by the photosynthesis of
plants in the green house" Journal of the Japanese solar energy,
vol.22, No.4, p34-37(1996).
In the beginning, it was planned
a short experiment with ponds of plywood frames, because the alkalinity
of concrete does not work well for experimental purposes. Recently, the
ponds were changed to use reinforced concrete walls so as not to have
any leakage and a variety of water grass have been tried. The following
is a report on the present situation.
evacuation wastes of a household must be returned after cleansing. If
each home makes the effort, an infrastructure may not be necessary.
Excrement is processed into biogas and the gas is used for cooking. The
rest of pollutants, i.e. carbon dioxide after cooking, drained soap
water from sinks, a shower room, a washing machine and kitchen sinks,
so called grey water, must be cleansed. In this project we rely for
cleansing on the photosynthesis of plants. Carbon dioxide after cooking
is guided through an air duct to the greenhouse. Grey water is
collected in the agitation pond and sent to the next cleansing ponds of
zig zag channelling where plants grow. There are a few systems like a
wet land system which process with plants in a pond or a greenhouse.
Most of them treat excrement and grey water together. Furthermore,
there is no system that treats the exhaust gas from cooking in the same
Cleansing ponds in the greenhouse
cleansing ponds that come after an agitation pond were constructed in
the greenhouse; their plan and section are shown in Fig.1-3-1. The
three ponds have sand layers with different depths and zig zag channels
for the water to run a longer course. The sand layer is expected to
have bacterial activity, and the longer the grey water runs, the
cleaner it becomes through the plants photosynthesis. The newly
constructed concrete ponds are shown in Fig.1-3-2.
Fig.1-3-1 The plan
and section of an agitation pond and three cleansing ponds.
agitation pond and three cleansing ponds in the greenhouse
addition, an air duct with an electrical fan takes the carbon dioxide
created after cooking into the greenhouse. The gas is cooled by the
outside air in the meantime and falls over the plants (see Fig.1-3-2).
The carbon dioxide is heavier than air at the same temperature.
the water after a shower still retains a higher temperature, it
bypasses a thermally insulated pond where the heat is used for the
fermentation of dough and then goes to the agitation pond as well. The
whole drained grey water is gathered in the agitation pond before being
moved to the first pond.
When the project was planned we
to do the following:bulrushes for thatch roof renovation in the first
pond, water hyacinths for biogas generation with active photosynthesis
in the second pond and watercress for food in the third pond. However,
the period of stay at the House was limited to only 4 months a year at
this stage and water use was unexpectedly not great.
especially even the first pond was not filled with water because of
active evaporation. We were told water hyacinths were noxious because
of their energetic propagation. As a result, the second and third ponds
were not used. In addition leakage was noticed and it was decided to
change them to concrete ones. The existing plywood was used as the
outside frame and concreted about 8cm thick with the reinforcement of
iron bars. The first pond is ca 1m deep. A concrete panel 2cm thick was
made with a 2cm mesh in the middle, to be a water guide for the zig zag
channel. River sand was placed ca 79cm deep. The level difference
between the inlet and exit was less than 5mm. Water was filled to a
10cm depth above the sand surface. The second and third ponds were made
with concrete too and were to get gradually deeper. In such a way, if
cleansing ponds are in a greenhouse, the grey water will not mix with
rain water and can accelerate plant photosynthesis because of the
warmer climate. This can be considered a part of solar energy use.
2) Plant growth in the first pond
was used for thatching the roof. About ten stocks were planted in the
first pond on 30/08/94 with the idea of using them for later renovation
of the roof. Spring was chosen for the transplantation. However, other
weeds started to grow as well. Some time later, I got a few stocks of
water reed from Norbert and planted them in the first pond. When he
brought the seeds to NZ from Europe, he received permission from the
quarantine office, but we were later told they are considered noxious
too. We noticed leakage in the first pond and decided to line them with
concrete. When we turned over the sand under the peacefully coexisting
weeds there was a layer of hairy roots from water reeds that was 30cm
deep. It might have given nutrients to them. A further surprise was
that under the layer in the sand thick roots of water reeds ran left to
right up and down showing a dominant strength of growth. This power
would easily overcome other water grasses in the same way as kikuyu
does to other grasses. We then understood the reason why they are
treated as noxious and burnt all the roots. Once we wanted to have
enough water reeds to thatch the roof and planted a few seedlings for
this purpose in the bottom field, but they were covered with weed mats.
3) The change to concrete ponds
concreting started in February 2003 and was finally over in the end of
September. Plywood was used for the outside frame, ready made iron
meshes were placed in the middle and concreting was done between a
movable corner for the inside frame and the outside frame. A separation
panel for the zig zag channelling was also made with concrete with a
2cm iron mesh in the middle. The thickness of the concrete walls is
somewhat not even due to our workmanship and the final dimensions are 6
to 8cm inside those of the drawings in Fig.1-3-1. To prevent leakage
the surface was painted. Sand was filled as in Fig.1-3-1 reusing used
sand as much as possible. The sand layer is expected to have bacterial
activity and also creates a filtering effect. Once we were told that
the planned grass was noxious we tried some other kinds of grass but
they still need further investigation. In summer, the sun is too strong
for them and a shade screen of 30% cut was stretched under the ceiling
of the greenhouse as protection.
In June, 2003, a few old
roots from the latest harvest were transplanted to the first pond. The
grass grew healthily with clear green shoots and looked to be growing
well in the grey water. It also grew grains earlier than the ones that
were in the rice paddy – their tops were already bowing by
January 2004 which was early. About ten seedlings were transplanted
from the seed bed at the end of the previous year, and they started to
produce grains as well. Azolla was put into the first pond and covered
the latter half of the pond. It looks like it is moving up towards the
mouth but more observation of this is necessary. However, the grains
were not well developed. This might be because the pond was always
filled with water or because the energy was not sent to the grains, or
maybe because in the night the greenhouse gets colder and aphids
attacked the grains because of the still warm air which they like.
the second pond, azolla and water cress exist but duck weeds are
dominant. Whatever is growing, the water at the exit seems already
The third pond has two water lilies, penny warts,
oxygen grass and eel grass. As the water level decreased quickly even
with the shade screen, another screen was added over the pond. The
decrease was thought to be caused by evaporation and photosynthesis.
The white surface inside had a lot of yellowish algae and the water
looked to be not that clean, but when it was scooped out by hand, it
looked very clean. Of course, final judgement should be made after
water tests. Recent observation concluded that the decrease of water
was caused by leakage at the joints of the concrete. We are going to
On the 26th of November 2005, we had hail stones
in our village area exclusively. Large ones in this storm were as big
as a golf ball. Locals who have lived here for a long time said that
they had never experienced this kind of unusual climate. The ground was
covered in white and the bird nets over the rice paddy could not let
the hail through and were broken at three stitched joints. The
greenhouse roof also got hit and 6 glass panes were broken.
is evident by inspection alone that the water in the third pond is much
cleansed. It runs through zig zag channels to three differently
designed ponds. While it does this plants and bacteria in the sand
layers analyse and absorb ingredients in the grey water. The additional
carbon dioxide, the warmer climate in the greenhouse from the mild
local climate make the plants grow well and have active photosynthesis.
For better cleansing we get rid of any floating grass from time to
time. It will be interesting to see the effect if we make the width of
channelling panels narrower, thus letting the water run further. By
investigating the air density measurements we should be able to find
how much carbon dioxide is changed to oxygen through photosynthesis. It
should also be checked by water testing how much nitrogen, phosphorus
and other ingredients in the grey water are absorbed and eliminated
through the ponds.
The most appropriate and best species for
third pond could be a future subject of investigation. We will visit a
few lakes to see floating grasses. Evaporation through high
temperatures can be counted as cleansing. The active growth of the
plants is the absorption and storage of solar energy and could be used
as an energy source. A part of this could be given to the septic tank,
part could be compost, and part could be food etc. It is interesting to
look at a plant from a variety of angles. If a greenhouse is to be used
just for cleansing the grey water and carbon dioxide from family use,
it could be smaller than at the Experimental House.
agitation pond looks to be within the limits for frogs to be able to
live in. They eat mosquito larvae and as a result not many mosquitos
are seen in the greenhouse. They have a new ecosystem there. The other
ponds offer more comfortable environments to live and some forget to
hibernate. It is meaningful to use a greenhouse as a solar energy
collector but there is a question over how negative radiation in the
night could be treated. It might be worth investigating how the
environment would be changed and used if a cover is used for thermal
insulation and to intercept the radiation.
In such a way, by
treating the carbon dioxide and grey water, I believe the harm to the
environment is dramatically decreased. I want to emphasize again here
that a pollutant must be treated and processed cleanly at the source.
This should be the hard and fast rule for any contamination. Nature
lets us live and we must not fiddle and meddle with it. Under the sun,
each one's life should not put a load on nature – it should
closed system. Then nature is welcoming, flowers, birds, insects, small
animals etc come by themselves and we find delight and joy.
(4) Self-sufficiency based on organic
the basis of (1) to (3), if we produce our own foods based on organic
farming, we need not earn money from others, and then we are liberated
and can become free.With this, we can proceed to joy and happiness.
are surrounded by a world full of unnatural human products; chemical
fertilizers, herbicides, pesticides, genetic engineering etc. We need
to strictly protect ourselves in order to 'survive'.
at the Experimental House is not one of large scale production.
Depending on one's taste and given time, we can properly plan to
efficiently get necessary nutrients and then we need not work very
hard. In my case, rice is the primary crop. If brown rice is eaten, a
variety of nutrients are included such as essential amino acids,
vitamins, starch etc. I need not grow much of any other food. Soya
beans are the important supplier of protein. Black sesame is necessary
for anti-oxidization. I want to eat salad and vegetables in season. As
animal protein egg is essential.
One of my friends said that
agriculture goes well through experience. I think this is very true.
After failures one learns the way and the joy in success is great.
However, as time is limited, without the exchange of one's experiences
and information, proper growth will be hard to get.
2000 years in its history of rice growing, which means 2,000 times of
trial and error. However, if 2,000 people cooperate and analyse their
results with knowledge and information, a good method can be worked out
in a short period and a local place gets the best way to grow for their
specific conditions. This applies not only for growing rice, but for
all other crops as well. As this project is diverse, I could not spend
much time on agriculture, but by slowly getting experiences and
establishing a daily work routine, I have enjoyed growing crops.
soil in the hill is clay and it is very difficult for plants to root
deep into this. The clay can become hard like concrete and provides
little nutrients for plants. The bottom part is most fertile because
sand and nutrients were deposited there by the creek in front. The soil
on the foot of the hill which faces south is clayish, but softer than
the one on the hill. We have carried fertile soil to the hill top as
time has permitted. A vegetable garden should be close to the kitchen.
A vegetable garden was started on the west side of the house measuring
about 70m2. However, the soil is of two extremes, hard or pulpy and
difficult to work.
Further, kikuyu grass which was brought
Africa grows very quickly and reaches sometimes to a depth of 40cm. It
took quite a while to get rid of the kikuyu. While I was commuting
between both countries I could not do much to it. Kikuyu grass is one
that is considered an African grass in a book on photosynthesis. It
says that most grass
Kazuo Shibata; "Light and plants: energy
and entropy at photosynthesis", Baihu-kan, 1982.
a photosynthesis efficiency of 4.7 to 4.8%, but kikuyu has 8.1%. Any
other grass can not supplant it. If it is together with other grasses
in an area it takes over completely. Indeed, in the past 50 years since
it was introduced to NZ, meadows and lands have been almost covered by
it in Northland. It keeps growing through the year. Farmers need not
have any animal barns as they can just provide hay from the meadow
(grown in summer). While it may be a good grass for stock purposes for
other agriculture it is very troublesome. At the Experimental House
considerable time was needed to suppress it. Various things were tried
- turning kikuyu over with a hoe and pulling it thoroughly, or covering
it with a wide weed mat. As growth appears to be suppressed under pine
trees, putting pine leaves under the weed mat was tried. The
introduction of this grass is one of the worst examples of
inconsiderate human thought.
Since I resigned from
University at the age of 60, I have worked steadily with limited time
for 8 years, but I still have to improve the soil further. The only way
to do this is to mix compost in. Kikuyu can be good compost. Although
it was only for seven months, I had a sheep at one stage and added his
manure. He died of facial eczema leaving me with wonderful memories.
gardens are dotted through the property. One of 70m2 is on the hill,
the second one of 30m2 is on the southern foot of the hill and called
the middle island, and the third one of 30m2 is on the bottom next to
the rice paddy and called the lower island. The latter two were places
where kikuyu grass grew. Each vegetable garden has a different soil
quality and gives me an interesting comparison.
of 131m2 produced 60kg in 2001, 80kg in 2002, 48kg in 2003, 78kg in
2004, 66kg in 2005, and 38 in 2006. The amount harvested is affected
not only by the climate of the year, but also shows a biannual
behaviour pattern (except for 2006). The unexpected harvest of 2006 is
discussed in Chapter 5. I am pretty sure that NZ can grow rice well. In
terms of efficient land use, I don’t need to use any other
while the paddy is out of rice growth. All the old roots were left in
autumn 2005 after the harvest, covered with black plastic sheets to
suppress couch grass. However the 2006 year harvest was very bad. I
think this was caused by the covering sheets not allowing enough sun
light and oxygen to reach the roots in spring. This result is discussed
in the chapter 2.
A vegetable garden for a four member family
at least 100m2 of land. My aim is that to always have something with
the proper nutrient balance growing throughout the year. I grow two
kinds of soybeans, one is a NZ variety and another is from the edamame
species. I have harvested these for three years. The edamame grows more
and larger pods. A black sesame produces a sprout. Vegetables were sown
a bit earlier in the middle of September and many of them flowered.
Shifts in sowing should be done.
fertilizers: 16 elements are necessary. C, H2, O2 are taken from air
and the ground. The other 13 are from soil. N2 for leaves, phosphoric
acid for fruits and plenty of potassium for the roots. Calcium for root
tops, magnesium for chlorophyll and sulphur for protein must be added
appropriately. Seven trace elements are required - iron, manganese,
zinc, copper, boron, molybdenum and chlorine.
The liquid in
section of the Ozeki septic tank is composed of non-organic substances
after all the organic matter is decomposed. It must include the above
elements - especially the trace elements. It is said to having good
soil gives a good environment for microbes. For farm work, some books
in Japanese language, for instance, one by M. Fukuoka, one by G. Tokuno
etc, were used for reference.
of July 2005, the following crops are grown and harvested. See
Fig.2-2-2 in chapter 2.
(Yukihikari from Hokkaido), potatoes (Maori, red and white), Kumara
(sweet potato), buckwheat, soybeans (NZ, edamame): they are possible to
grow from the middle of Oct. to the middle of Dec, broad beans, red
beans, kidney beans, sweet corn.
mizuna, pak choi(2 species), kale, komatsuna, a variety of lettuces,
cucumbers(three species), tomatoes(14 species), chicory, melon, water
melon, broccoli, cauliflower, Brussels sprouts, Spinach beet, silver
beet, spinach, zucchini, cabbage (green, purple), snow peas, pumpkin (2
species), Egg plant (2 species), leek, green pepper, Japanese pepper,
okra, nira (garlic chive),
Beetroot, radish, daikon (2
turnip, burdock, carrots (3 species), onion, yacon, asparagus, Japanese
shallot, Japanese taro, Japanese yam,
Hot chilli, shungiku,
grapefruit, lemon, fig, apples (Fuji and Golden delicious), kiwi, cherry
(2 species), apricot, peach (yellow), mulberry, olive, strawberry,
chestnut, hazelnut, almond
and nut trees not yet harvested
nashi pear, citrons,
macadamia, avocado, walnut etc
listed above, quite a number of crops are harvested at the site and I
continue to learn. Though I have to suppress kikuyu and improve the
soil quality, if I plan and work better according to the season, the
mild climate will help me. However the present crops alone give me rich
nutrients and a healthy diet. Planning is important - when crops should
be planted and harvested, and what quantities are necessary. Weeding
must be done frequently, because weeds are so energetic. Using the
smallest area required means less weeding is necessary. Potatoes
continue to grow on and on and hinder planned work. I bought a few
sackfuls of sheep manure from a boy scout. I also got manure from my
sheep later on, but he died because of facial eczema. Chickens could be
a replacement source. Some crops need their growing plans changed now
to harvest them longer. When a new branch comes out between a stalk and
an established branch, it should be taken off for tomatoes, egg plants,
peppers etc. In order to make the stalk healthier, first fruit should
also be removed. After a vegetable garden is established, I want to
apply Fukuoka's natural farming with no cultivation and no fertilizer.
few views of my vegetable gardens and rice paddy are given in figures.
Scenes of the rice paddy.
vegetable garden 1
vegetable garden 2
of the vegetable garden and fruits trees.
the production of crops alone does not give you any food. Cooking is
the next issue. In the beginning of summer 2003 with the help of a few
young people we started concreting the ponds in the greenhouse. I
cooked for them my brown rice and stir-fried the vegetables of the day.
The latter dish was cooked only with pepper and salt as seasonings.
Every dish used tomatoes and zucchinis, and it looks like the
ratatouille from Province, South France. I call it Kaiwaka ratatouille
of the day.
Though I have not yet produced food such as oil,
and grapes for wine, I received a good confidence boost about food
production as I was able to serve every day so many wonderful dishes to
hungry young people. Oil will be squeezed from olives and black
sesames, salt will be made from sea water being boiled in the solar
cooker. The water left after crystallising salt will be used to fix the
protein of soybeans into a tofu. fermentated soy beans, i.e. natto and
brown rice with red beans are highly essential foods for me. They are
said to be good against thrombosis and have many health benefits. I
want to grow mushrooms and shitake mushrooms.
be energy saving as well as able to cook well. I mentioned earlier a
cooking tool which uses the thermal insulation of vacuum called Shuttle
Chef, one which does not waste the flame heat giving a skirt around the
pot called Hakase Nabe, and our handmade thermal insulation box with
fleece. Avoiding Teflon treated frying pans, I got an enamel processed
one made in France. Because it is heavy and keeps heat well after
cooking, the taste is improved. If we look at daily cooking, we would
be able to find a lot of areas to improve.
that I have learnt to make with ingredients grown at the Experimental
vinegar pickles of sliced turnips and radishes, salad leaves of turnips
and radish squeezed with salt, pickles of Japanese shallots, sukiyaki,
fried rice, stir-fried vegetables, noodle soup, schnitzels of meat and
fish, cucumber squeezed with salt, salted Chinese cabbage, baked
potatoes and sweet potatoes by the solar oven and so on.
tofu; soak 1 soybean in 3 water over night, crush it with a blender,
and boil it for 5 to 6 minutes. Stir it so as not to burn on the bottom
and get rid of foam. Keep at 70 degrees and mix in bittern to fix the
protein. 9gr of bittern to 100cc of soy milk is what is needed.
a variety of energy given by the sun, constructing a house of
comfortable indoor climate using local materials, not contaminating the
house surrounds in order to blend into nature, and being
self-sufficient based on organic farming, we are able to use leisure
time freely. Finally, one is liberated and becomes free. I have been
doing my best to establish the sustainable way of living as soon as