Solar powered stirling engine for self-generating electricity

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In the energy deficient world, it is strongly felt that the use of solar energy as a possible source is not being fully utilised. So in an attempt to deploy its use, a novel concept of “solar powered stirling engine” is introduced in this paper. At present there are no solar powered Stirling engines ready for use in many countries. The Stirling engine used here runs using solar power from computer controlled solar beam concentrator. Stirling engine is unique in its sense that it uses only two pistons for its operation to produce motoring action unlike the conventional motors. A Stirling engine is basically a heat engine that operates by cyclic compression and expansion of air or other gas, the working fluid, at different temperature levels such that there is a net conversion of heat energy to mechanical work. This solar powered Stirling engine is coupled with a generator to produce power. The generator is usually a linear alternator which helps in reducing the number of moving parts and linkages that are required in a conventional generator arrangement. Moreover, the gas bearings provide a non-contact frictionless surface for the piston, thus eliminating the need of maintenance. Provision for storage of solar heat using salt storage system is implemented to make use during its absence. The Stirling engine is noted for its high efficiency (up to 40%), quiet operation, and the ease with which it can use almost any heat source. It has the ability to utilize effectively any burnable fuel, such as wood, rice husk, straw, agricultural waste and other readily available and cheap combustibles. This compatibility with alternative and renewable energy sources has become increasingly significant as the price of conventional fuel rise. This method of power production has no pollution, no noise. Incredibly, the absorber in the concentrator is very small (10″ × 10″) but has the ability of providing 10kW per hour. This is proven to be the most efficient way to convert solar energy to electric power. It is twice efficient and five times cost-effective than the conventional method using Photo voltaic cells. This engine is currently exciting interest as it is more efficient and safer than a comparable steam engine. Stirling engines are also being looked by NASA for the use in space exploration.