Thermodynamic sustainability assessment for residential building heating comparing different energy sources

Abstract

Residential sector is considered one of the largest consumers of primary energy in the world. The main part of total energy consumption in buildings refers to heating. The study presents a thermodynamic sustainability assessment of different energy sources for residential building heating. The paper presents universal methodology, which can be applied to energy and exergy analysis for all types of buildings. Various options of energy sources were studied, namely: coal, natural gas, electricity, district heating, air-water heat pump, biomass and district heating with a cogeneration. Energy and exergy analyses were conducted and appropriate efficiencies were determined. The calculation of an environmental impact factor and exergetic sustainability index for all types of considered energy sources was performed. The results showed that exergy efficiency was very low in all analyzed cases except for biomass, which leads to poor thermodynamic compatibility of energy quality from the supplied side and the energy used for building heating. It was shown that the highest exergy efficiency was in the case of biomass utilization (about 29%), due to the energy used from renewable energy sources. The minimum environmental impact factor (2.48) and maximum exergetic sustainability index (0.403) were found for the case of biomass utilization.