Apart from photovoltaic cells, there is another way to produce electricity with the Sun. This technique uses the Sun to heat water or air in a closed tank. High temperatures are reached by using parabolic mirrors which concentrate the Sun's rays. The heat increases the volume of water or air in the tank creating pressure which is then released to operate a turbine linked to a generator.
This technique uses the same principle found in thermal or nuclear power plants but with the Sun, a clean and renewable energy (instead of coal, petrol or uranium).
This solar popper project uses the same principles and manages to boil water in a test tube and expel a plug. This demonstrates that it is possible to transform the heat of the Sun into motion.