Auxiliary Energy Sources and CO₂ Emissions in Solar-Assisted Heating

This study evaluates the environmental performance of a solar-assisted heating system under the climatic conditions of İzmir by comparing five auxiliary heat generation technologies, namely a heat pump, natural gas boiler, oil-fired boiler, wood-fired boiler, and district heating system. Dynamic simulations were performed under identical operating conditions using T*SOL software. The solar subsystem, climatic data, thermal loads, and control parameters were kept constant in all scenarios to isolate the influence of the auxiliary energy source. The results indicate that all investigated systems exhibit comparable thermal and energy performance characteristics. However, notable differences were observed in environmental performance due to variations in the carbon intensity of the auxiliary energy sources. The findings demonstrate that the environmental benefits of solar-assisted heating systems depend primarily on the selected backup heating technology rather than on differences in thermal performance. Therefore, the integration of solar energy systems with low-carbon auxiliary technologies is essential for maximizing greenhouse gas emission reductions and improving overall sustainability.