Designing Ecological Habitats - Gaia Education

tHe solar village of tamera : tecHnical & ecological knowleDge for peace villages 177
in Portugal. “Very quickly we had the vision to get this Sunpulse machine
ready for production and economically affordable,” Paul continues. “This is
one of the things we are working on now.”
The Sunpulse and most of the other solar systems were developed by
the German inventor Jürgen Kleinwächter, a physicist who has dedicated
his work to inventing technologies which make the life of the poorest people
in the world easier. “Many women of African villages have to walk 20 or
30 km per day to find firewood,” Jürgen says. “For them I developed solar
systems which can be built with local means and can be used for the most
urgent needs, like producing heat for cooking, energy to pump and clean
water, and electricity.”
The SolarVillage team in Tamera works closely together with Jürgen to
further develop his inventions under real-life conditions. Jürgen adds, “In
this way practical solutions will emerge that are suitable for the future while
simultaneously improving the quality of life”. The core of the SolarVillage
is a 25m-long energy greenhouse. Under its roof, lines of transparent lenses
are mounted – Fresnel lenses which focus sunlight onto a tube. Through this
tube plant oil flows, heated by the sun to more than 200ºC. The hot oil is
then stored in a tank and can be used for cooking day and night. Called the
‘Sunpulse Hot Oil’, it can also be used to provide electricity (1.5 kW) from
the thermal energy.
In addition, the community kitchen of the SolarVillage uses SK 14
parabolic reflectors, cooking cases, and the Scheffler Reflector. Large,
impressive, and shining, the Scheffler Mirror is a 10m 2 parabola – a sun
reflector with a fixed focus, meaning that the sunlight is focused on a fixed
point that is the cooker. It is designed in such a way that the burning point
remains fixed and does not wander by constantly adjusting the mirror’s
position to the sun. The German Wolfgang Scheffler invented this adjustment
mechanism based on the principles of a mechanical clock, made from parts
of bicycles. On a sunny day the fixed focus for a solar oven, for instance, can
be run without needing any manual adjustment. Through this fixed focus of
the Scheffler Mirror, the construction of solar kitchens is possible, since the
mirror supplies continual condensed light energy.
The basic idea which led to the development of the Scheffler Mirror was
the desire to make solar cooking as comfortable as possible and available
indoors. Depending on the season of the year, the output of a reflector with
a surface of 10m² varies from between 2.2 kW during summer and 3.3 kW
during winter with a sunbeam input of 700 Watt per m 2 .
Another solar system in Tamera, which is mainly used during the harvest
times, is the solar dryer. A roof of plastic is mounted over a grid where
tomatoes, apples, herbs and oranges are drying. A fan run by solar energy
keeps the air dry and clean and prevents molding. “The solar dryer was
built in a very short time out of literally nothing,” Barbara Kovats states,
“Now it provides us with dry fruit all year long. It allows us to preserve the
abundance of the summer. For a village this could be a small business.”
For Paul Gisler, these easy-to-build developments are merely the