Techno-economic and environmental analyses of a solar-assisted Stirling engine cogeneration system for different dwelling types in the United Kingdom

Abstract

In this study, a hybrid cogeneration system that combines photovoltaic-thermal (PV-T) collectors with a Stirling engine, and a battery-pack-based energy option is proposed for residential applications. The system’s purpose is to fulfil the electrical and heating requirements of different types of houses in the United Kingdom, including detached, semi-detached and mid-terraced houses. This study includes a comprehensive assessment of the techno-economic feasibility and environmental impact of the proposed integrated energy system, after determining the appropriate sizing of the system’s components for the three different house types. The exergy efficiency of the integrated system for detached houses (with a 1 kWe-Stirling engine plus 28 m2 of PV-T collector array) is found to be higher compared to that for the semi-detached and mid-terraced house configurations, with the highest efficiency of 22 %. In terms of economic performance, detached houses have the lowest levelized cost of electricity (0.622 £/kWh), levelized cost of heat (0.147 £/kWh), and levelized cost of total energy (0.205 £/kWh). Furthermore, the system demonstrates the maximum potential reduction in CO2 emissions in detached houses. The achieved CO2 emissions reduction rates for different house configurations fall within the range of 30 % to 45 %. The proposed hybrid cogeneration system shows promise as an effective and sustainable solution to meet the energy demands of various residential house types in the United Kingdom, offering improved efficiency, cost-effectiveness, and substantial reductions in carbon emissions for detached houses.