Solar energy for low carbon buildings: choice of systems for minimal installation area, cost, and environmental impact

Abstract Solar application in buildings is limited by available installation areas. The performance of photovoltaic (PV) and solar collectors are compared in meeting the heating and cooling demand of a residential house using 100% solar energy through TRNSYS modelling of five systems that use air source heat pump and seasonal energy storage as optional assisting technologies. The results show that in a large scale, the PV working with air source heat pump is more efficient than the solar collector system. However, the photovoltaic/thermal (PV/T) is the most spatially efficient with an energy capacity of 551 kWh/m 2 , 10.6% higher than that of the PV. Compared with the air source heat pump heating system using grid power, using solar energy regardless of system formats can reduce emission by 72% in a lifetime of 20 years. Solar energy can become cost-effective if the utility price is increased to above 0.7 CNY/kWh. The results can help in renewable planning in the studied climate.