Effect of PVC greenhouse in increasing the biogas production in temperate cold climatic conditions

Abstract This paper presents an investigation on a new concept of greenhouse coupled biogas plant for enhancing the biogas yield during winter months when the slurry temperature decreases considerably. Using this concept, two of the biogas units (having a capacity of 8 m3 and 85 m3, respectively) at Masoodpur Village (near New Delhi), were experimented upon in January 1984. Continuous observations for about 1 week, 1 yr after installation of the greenhouse over the biogas units, have indicated that the biogas yield has increased by almost 100%. Subsequently, an analytical model has also been developed to validate the experimental observations and to predict the thermal performance of biogas plants, with and without greenhouse, under any climatic conditions. It has been observed from a comparative study of the conventional and the solar-assisted greenhouse coupled biogas plant that the temperature of the slurry can be raised from 20°C (in the conventional plant) to nearly 35°C, the optimal temperature for anaerobic fermentation.