HEATING CHARACTERISTICS OF A SOLAR-CO₂ AIR SOURCE HEAT PUMP COUPLED SYSTEM WITH VALLEY-ELECTRICITY HEAT STORAGE
Keywords:
Solar energy, CO₂ air source heat pump, TRNSYS, Heating performanceAbstract
Taking the heating system of a rural household in Yinchuan as the research object, a simulation model of a solar-CO₂ air source heat pump heating system was developed based on TRNSYS, and its operation from November to March of the following year was simulated and analyzed. The results show that the system can reliably satisfy the indoor winter heating demand of rural households, with heating temperature fluctuating little and remaining stable at approximately 18.0 ℃. Regarding the electricity consumption of the coupled system, the energy use of the space-heating pump and the heating circulation pump rises in step with the extreme-cold heat load in winter, showing a pronounced negative correlation with outdoor temperature; in contrast, the energy consumption of the solar collector pump is governed solely by solar irradiation and remains stable throughout the entire heating season. Over the whole heating season, the collector harvested 6,276.26 kWh of heat and the air source heat pump delivered 6,359.19 kWh, the two contributions being nearly equal, with the total heat output of the heat pump slightly exceeding that of the solar collector. The carbon emissions of the solar-coupled heat pump heating system are only 1,433.94 kgCO₂, equivalent to 24.5% of those of a coal-fired boiler (the highest-emitting option), demonstrating remarkable energy-saving and emission-reduction effects. This study aims to refine the theoretical framework of solar-CO₂ heat pump coupled heating and to provide data support for the engineering design and operation-and-maintenance optimization of clean heating projects for residential and public buildings in cold regions.References
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