energy conservation; solar water heater; solar energy; flat-plate collector
An attempt is made to conserve conventional fuel by use of solar energy. For a given energy demand pattern, conventional fuel can be saved by replacing it with a solar hot water system for domestic applications, including cooking. Numerical computations are also done for the payback period of the solar hot water system in a dynamic economic environment. It is concluded that (a) the payback period is exceptionally low for complete replacement of electricity (4.98 yr) round the year, and for the replacement of other fuels, like firewood, cooking gas and kerosene oil, the payback period is around 10 yr, and (b) the solar water heater is very economical for round the year use.