South Africa is currently facing a two-pronged energy crisis a shortage of electricity and oil at over $100 a barrel. The sun produces enough energy to provide for almost all of the power requirements of the world if this free energy can be harnessed. South Africa is blessed with a climate that is dominated by sunshine, making it an ideal candidate for developing solar power to complement and possibly replace the use of fossil fuels in the production of electricity.
An associate is developing a domestic solar power system using alternative technology. If this works, this could cause a revolution in the generation of electricity as the majority of people in sunny climates could become self-sufficient in their electricity needs. The bonus is that the energy is free, infinitely renewable and does not produce any harmful emissions.
Two main systems are currently in use for harnessing the sun energy. The use of solar panels to provide hot water using the sun’s thermal power, and photo volactic or PV panels that transform the sun’s light emitting properties to produce electricity.
A third route is to use the sun’s thermal power to produce electricity. The world’s largest solar powered generator is in development in Israel’s dessert area the Negev. The system uses a huge array of curved mirrors to heat oil that in turn heats water to produce steam. The steam powers large turbines that produce electricity that can be distributed as part of the national electricity grid. The heat produced exceeds 260 degrees Celsius.
The still to be developed domestic solution works on a similar but scaled down principle. Mirrors with a sun-tracking device focus the sun’s rays onto a small area. The heat produced is used to power a small steam turbine that produces electricity directly to the household. Surplus power is stored in large purpose built batteries to provide for night-time power needs. At present the main unknowns are the amount of space required for the mirrors. Will the average household have enough space to be able to use this system effectively, or will it be necessary to move to a power sharing system where one unit is used to power several houses?
The more established systems are currently being used for thermal heating to supply the majority of a household’s hot water needs. This has been widely used in Israel for the last fifty years. For other household requirements PV panels have been used effectively to provide lighting and other electrical requirements. The main problem of using the PV system is that it requires a huge investment to provide for even a portion of current electricity needs.
One company that has employed solar power in its buildings is BP. The roof of its Cape Town head office is covered in PV units, and the entire building has been designed to be energy and light efficient.
At present there are limitations to using solar power. These include the prohibitive cost of PV panels and the amount of sunshine available per day to tap into. PV panels are able to make use of light even when the sky is overcast, but electricity cannot be generated directly from the sun during the night. Harnessing solar energy to produce power has not been a top priority of most governments in the past, but the potential for solar power as a major source of energy is a reality.
