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The production of low-cost wind generation through decentralized power stations in India is discussed.

The evaluation of the financial aspects of biomass gasifier power projects for the decentralization of power supply in India, based on the usage of dual fuel engines and 100% producer gas engines, isn presented.

A generalized analytical equation for the top heat loss factor of a flat-plate collector with one or more glass covers has been developed. The maximum computational errors resulting from the use of the analytical equation with several simplifications are + or - 5 percent compared to numerical solution of the set of heat balance equations. The analytical equation is considerably more accurate than the available semi-empirical equations over the entire range of variables covered. An additional advantage of the proposed technique over the semi-empirical equations is that results can be obtained for different values of sky temperature, using any given correlation for convective heat transfer in the air gap spacings, and for any given values of fluid (air in the present case) properties.

An approximate method for calculation of the hourly output of a solar still over a 24-hour cycle has been studied. The hourly performance of a solar still is predicted given the values of the insolation, ambient temperature, wind heat-transfer coefficient, water depth, and the heat-transfer coefficient through base and sides. The proposed method does not require graphical constructions and does not assume constant heat-transfer coefficients as in the previous methods. The possibility of using the values of the heat-transfer coefficients for the preceding time interval in the heat balance equations is examined. In fact, two variants of the basic method of calculation are examined. The hourly rate of evaporation is obtained. The results are compared to those obtained by numerical solution of the complete set of heat balance equations. The errors from the approximate method in prediction of the 24-hour output are within + or - 1.5 percent of the values from the numerical solution using the heat balance equations. The range of variables covered is 5 to 15 cms in water depth, 0 to 3 W/m squared K in a heat-transfer coefficient through base and sides, and 5 to 40 W/m squared K in a wind heat-transfer coefficient.