The sun in 15 minutes provides us with enough energy for all our needs for 1 year. It costs nothing and does not pollute at all. Although the energy reaching the earth from the sun is enormous, its intensity is so low that a large car if driven by solar power would require a collection of 600 square metres - about the area of 6 average homes. At present equipment to collect the sun's energy is very expensive. The cheapest method is to use flat plate collectors to heat water.

In sunnier climates large schemes have been proposed. French scientists in the Pyrenees have reached temperatures of 4000°C which will melt diamonds, using a whole hillside as a collecting area. A team in Berkeley University, California, are trying to obtain energy from chlorophyll, the green colouring of plants that is reponsible for photosyntheis. Another suggestion is to build solar power stations in space and beam solar energy to earth as microwave power, but development costs are likely to stop this project even if the technology could be solved.

SOLAR CELLS