In today’s climate of growing energy needs and increasing environmental concern, alternatives to the use of non-renewable and polluting fossil fuels have to be investigated. One of such alternatives is solar energy. Solar energy is quite simply the energy produced directly by the Sun and collected elsewhere, normally the Earth. The sun creates its energy through a thermonuclear process that converts about 650,000,000 tons of hydrogen to helium every second. The process creates heat and electromagnetic radiation. The heat remains in the sun and is instrumental in maintaining the thermonuclear reaction. The electromagnetic radiation (including visible light, infra-red light, and ultra-violet radiation) streams out into space in all directions.

Only a very small fraction of the total radiation produced reaches the Earth. Much of the world’s required energy can be supplied directly by solar energy. More still can be provided indirectly. Among the renewable resources, only in solar power do we find the potential for an energy source capable of supplying more energy than is used.

Due to the nature of solar energy, two components are required to have a functional solar energy generator. These two components are a collector and storage unit. The collector simply collects the radiation that falls on it and converts a fraction of it to other form of energy (either electricity and heat or heat alone). The storage unit is required because of the non-constant nature of solar energy; at certain times only a very small amount of radiation will be received. At night or during heavy cloud cover, for example, the amount of energy produced by the collector will be quite small. The storage unit can hold the excess energy produced during the periods of maximum productivity, and release it when the productivity drops. In practice, a backup power supply is usually added too, for the situations when the amount of energy required is greater than both what is being produced and what is stored in the container.