added to cache on November 30, 2007

Sabine Lichtenfels (english)
Solar Village
May 1st: The first solar soup

Solar Village update Nov 2006

Sol e Adobe

The Project of the Solar Villages
Solar Power by regional means and without large industry
An eco-village, as a proto-type of the global future village, needs an environmentally friendly and decentralised energy supply that can be produced by regional craft companies and independent of large industry.
This is the vision that solar technologist Jürgen Kleinwächter and his enterprise Bomin Solar in Lörrach/Germany has been working on for decades. He has developed a model for solar energy supply to an African village with 50 inhabitants, the Solar Power Village;. Without photo voltaic it produces energy for cooking, pumping water, wheat milling and electricity. In order to build a first 1:1 - model of this village in Europe he is working in cooperation with the Healing Biotope 1 Tamera because, as he says: Only a community can guarantee the social and cooperative form of living that is necessary for ways of living with an autonomous supply of energy.
How did the Solar Power Village develop?
During a field study in villages in West Africa Jürgen Kleinwächter noticed the needs of the people there. In the Sahel zone women walk an average of 40 km per day, only to collect wood. Then they crush wheat for 1-2 hours. At the well, which becomes deeper and deeper, they have to pump the water with their own muscle power. Children become sick due to the bad quality of water. The vegetable gardens suffer from the wind and the heat in this arid climate. For all these problems, which - if they remain unsolved - lead to rural exodus, he developed an alternative: The Solar Village.
He says: Solar cooking reduces deforestation, desertification and erosion. This simple technology allows for local production, i.e. decentralized work places. What is new about the system is the applied solar technique which can be produced independently of industrial production in regional craft outlets.
The Solar Power Village is a combination of various modules which serve the production, storage and use of solar energy. The single modules will be described in detail below.
Module 1: The Green house
Under the roof of a 30-40 sqm sized green house this size may not be adequate for European conditions, a row of fresnel lenses are mounted and follow the movement of the sun. The fresnel lenses focus the sunlight on a focal line. In this focal line, there is a receiver through which vegetable oil flows. Kleinwächter: Vegetable oil is available everywhere in the 3rd World. Here the oil serves as a carrier of heat. As the oil flows through the concentrated energy zone it heats up easily to 220°C. The green house is covered by a highly transparent and long living (25 years) layer. This allows - among visible parts of the sunlight spectrum - especially UV to pass through, thus we have several advantages. The direct sunlight is received by the receivers, the diffuse light gets through into the interior of the greenhouse.  The good clima supports the growth of vegetables underneath. Kleinwächter: "The temperature in the green house is as confortable as a day in spring, and allows the growth of salad even in the summer", Kleinwächter declares. "By the way, because of the UV-light the vegetables are of a very good quality; you can not compare it with the usual products from green houses.
The special layer belongs to the few parts of the Solar Village that can not be produced in regional work. From the green house the oil then flows into a heat storage.
Module 2: Storage
The oil is stored in a large, well insulated cylinder; which can also be locally produced. The hot oil store allows 24 hour usage and avoids the use of expensive and environmentally degrading batteries. It provides autonomous energy for several days. As a second heat storage Kleinwächter developed a chemical, but environmentally friendly storage, a Magnesium Hydrate Alanate Storage, which can not be described comprehensively here.
Module 3: Cooking Place
In the Solar Power Village cooking is done in a specially developed cooking place. The hot oil flows through double plates, which have the form of cooking pots. With the temperature of the oil (220°C) one can fry, cook, and bake around the clock. "Through which the first dream of the African women would be fullfilled", Kleinwächter tells happily. "One can regulate the temperature and have the same comfort as with an electrical stove."
The cooking places can also be produced locally and would support the regional economy.
Module 4: The Stirling Motor
Another part of the hot oil flows into the low temperature stirling motor. This machine uses the temperature difference between the hot oil and cold water, in order to produce mechanic energy. This energy can be used in different ways, f.e. to move a flywheel and by this either wheat mills, water pumps or to produce electricity. All three possiblities of usage have been built and tested in the laboratory of Sunvention; the water pump has been developped the furthest. In 2004 in Lörrach, the Enterprise Sunvention together with technolgists from Tamera, built up the first model of the Solar Power Village.
Kleinwächter: Technically it works. What is lacking is a group of people who build up a 1:1 model for about 50 inhabitants, who really live there and use it, as a research and study model that can be visited and studied by people from so called third world countries.He is sure he has found this group of people in Tamera.
Here exists a huge amount of experience in cooperative living; this is necessary because energy consumption in single or small family households is too great. A form of living with autonomous energy supply in the sense of organic, decentralised technology needs a communitarian form of living. In Tamera one considers the implementation of this village as an inter-disciplinary research project.
The technologists, architects, ecologists, crafts people and those who deal with social design want to develop a complex, self-sufficient and socially sustainable model village in which the pioneering solar technology of Jürgen Kleinwächter could be integrated.
This projects needs funding. For more information:
Healing Biotope 1 Tamera, Monte do Cerro, 7630 Colos, Portugal
Tel. 00351-283-635306,
Print Version