Solar assisted biogas digesters I: Thermal analysis

Abstract

A thermal analysis has been made of a number of viable solar systems, namely (i) a solar canopy, (ii) a shallow solar pond (SSP) water heater, (iii) insulation and (iv) an SSP with a solar canopy around the digester, to boost the biogas production in conventional KVIC biogas plants during the winter months. Numerical calculations for a typical sunny winter day (17 January 1984) in the climate of New Delhi show that an SSP water heater on the top of the gas holder, covered with a solar canopy, is a good option from thermal point of view.