Model Construction and Performance Analysis of a Solar Energy and Above-Ground Biogas Digester Complementary Coupling Energy Supply System

Abstract

A rural household complementary coupled energy supply system based on solar energy and above-ground biogas digesters is established. Based on the dynamic mathematical model of the whole process of energy supply, production capacity and energy use of the system, taking Minqin typical new rural buildings in the cold area of northern China as the research object, the operation performance of the system is analyzed, and the multi-attribute benefit evaluation of the system is carried out. The results show that during the whole heating period, the heat supplied by the solar heat collection subsystem and the biogas production subsystem to the biogas digester is 10% and 9.29%. The heat provided by domestic hot water is 90% and 90.71%; The total heat demand of the system is 4636.22 MJ, and the total heating capacity is 4728.96 MJ, which can fully meet the energy demand of users. Compared with the traditional energy supply mode, the average CO2 emission reduction rate is 65.85%, the average NOx emission reduction rate is 98.13%, and the annual cost is 2014.17 yuan.

Keywords: Solar energy, Above-ground biogas digester, Rural energy supply, Complementary coupling system, Multi-attribute evaluation