Economic assessment and regional adaptability analysis of CCHP system coupled with biomass-gas based on year-round performance

Abstract

The combined cooling, heating and power system (CCHP) coupled with biomass-gas could meet energy consumption stably and have favorable thermal performance with a renewable energy contribution rate of 72.11%. The economic benefits of biogas-fueled CCHP system based on annual performance and regional adaptability are studied. Three government subsidy policies: direct government investment, electricity price subsidy for biomass power generation and government discount are selected to assess the effects of economic performance under different proportions. Net present value (NPV), investment payback period (PP) and internal rate of return (IRR) are used as economic evaluation indicators. Without policy subsidies, the NPV, PP and IRR in the cold area are 36,300 yuan, 12.26 years and 5.19%, respectively. Under the limitations of technology, the system is more suitable for areas with uniform cooling and heating load currently. Sensitivity analysis showed that the anaerobic fermenter and biogas slurry price have the greatest impact on the economic benefits. Based on electricity price subsidy (0.47 yuan/kWh), supplemented by direct government investment (20%) are suggested (PP is 8.0 years). It is proposed to form a unified mechanism of government lead, policy incline, enterprise investment and resident support for making the CCHP system coupled with biomass-gas develop vigorously.