Jan Braune, having experienced the stifling Indian summer with its ever present power cuts, is intrigued by the alternatives promised by solar power
Tamil Nadu is a sunny state and increasing numbers of people are interested in solar energy. But when people begin to speak about solar power in general, various things become mixed up. I visited the regional solar energy testing centre which is part of the School of Energy, Environment and Natural Resources, Madurai Kamaraj University, and the highly experienced and upcoming solar company SolSen in Madurai.
From the technical point of view, solar power consists of three main aspects: solar collectors, solar panels/ photovoltaic cells, and solar cookers.
With solar collectors, one can heat up water that can be used for preproduction, precooking or in larger hotels when they require warm water. Two different types of solar collectors are currently in use. The tube based collector with a tank on top (pic.1) has water delivered from the tank. Under the tank, vertical transparent tubes are used which in turn contain black tubes. The cold water in the black tube which comes from the tank is heated by the sun and forms steam, which rises up through the outer tube, is collected and can be used as hot water. The second construction uses a very small horizontal pipe work under a glass layer. The water coming out from the top pipe goes into the network, is heated and is collected at the bottom where it flows to the tank. Solar photovoltaic is more complicated in its technical construction, and produces electrical power which can be saved in batteries or can be used for direct consumption.
Silicium-based panels produce power through physical-electrical reactions with the help of crystals between different layers.
Solar cookers collect sunlight with the help of mirrors which focuses the sunlight on one point. If you are far away from an oven you can use this method for preparing your family meals.
Solar cars are still a distant dream for the public, but for restaurants and production companies, solar collectors are very interesting indeed. The number of customers is rising fast, effectiveness reaches up to 70 percent, investment costs are low, and more and more different models reach the market. Solar panels (photovoltaic) are not very common. In Europe, especially in Germany, many private households are using solar energy. But scientists are still conducting research to find better and more effective ways to collect and save the energy. In India, the prices of power are very low in comparison to European prices for energy and the panels are still expensive. In the last few years, China has started to produce panels and now the prices are being reduced very quickly, even when there remain many doubts about the quality.
SolSon in Madurai works in all fields of solar power and imports the majority of the relevant parts of their products from Germany and Europe. At the same time, they are looking for cheaper ways of production, due to increasing competitors in the market. According to them business is still going well, and a new factory is on its way in Tamil Nadu. In the future, probably Malaysia and Thailand will deliver the required machines.
Globalisation and global warming are taking place in the world and in Tamil Nadu annoying power cuts are part of every day life. Solar power is a promising alternative.