Techno-economic analysis of hybrid renewable energy system with solar district heating for net zero energy community

Abstract A techno-economic analysis of a hybrid renewable energy system, consisting of a solar thermal system, seasonal thermal energy storage (STES), heat pump systems, and district heating network for a net zero energy community has been conducted. Thermal and electric energy performance of the proposed systems were evaluated using detailed simulation models and experimental results of the Jincheon eco-friendly energy town in South Korea. Comparative environmental and economic analyses on two conventional systems that use gas-fired boilers (Case 1) and a centralized heat pump system (Case 2) were also performed. Assessment criteria in the environmental analysis include equivalent CO2 emissions and primary energy savings. The levelized cost of heat, a benefit-cost method and a payback period calculation were conducted to evaluate the economic benefit. The analyses were also conducted with different sizes for system components. Results showed that the increase in solar fraction of the proposed system reduces CO2 emission by up to 61% compared with Case 2 and enhances primary energy savings by up to 73% compared with Case 1. The levelized cost of heat was lower for the proposed system than the conventional systems. The proposed system showed a 6 year payback period and a benefit-cost ratio of 1.7.