Integrating multiple renewable energy sources into buildings is essential for achieving a net-zero carbon future, especially within the building sector. This study incorporates a photovoltaic-thermal (PVT) array in a conventional ground source heat pump (GSHP) system and presents four distinct designs that change based on system layouts and energy recovery mechanisms. Two innovative indicators, COPTLR and SCOPTLR, are proposed to effectively measure the efficiency of hybrid energy systems which include GSHPs, as well as to examine the overall utilization ratio of shallow geothermal energy. By applying numerical investigation, long-term systematic analysis is presented along with economic metrics and proposed innovative performance indicators. The findings indicate that the proposed cooling and heating retrofit mechanism, along with the implementation of a schedule control, can reduce the GSHP power consumption by 63.2%. Meanwhile, investment tax credit (ITC) and favorable retail tariffs can lower the long-term levelized cost of energy (LCOE) to 0.077 $/kWh. The minimum values of COPTLR and SCOPTLR in the proposed system are 0.492 and 0.483, respectively. This investigation fully demonstrates the advantages of the designed solar-geothermal system and highlights the effectiveness of the proposed performance indicators.

中文翻译：

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基于创新指数的太阳能地热系统与能源改造的比较分析


将多种可再生能源整合到建筑物中对于实现净零碳未来至关重要，尤其是在建筑领域。本研究在传统的地源热泵 （GSHP） 系统中结合了光伏热 （PVT） 阵列，并提出了四种不同的设计，这些设计会根据系统布局和能量回收机制而变化。提出了两个创新指标，即 COPTLR 和 SCOPTLR，以有效衡量包括 GSHP 在内的混合能源系统的效率，以及检查浅层地热能的整体利用率。通过应用数值调查，提出了长期系统分析以及经济指标和提出的创新绩效指标。研究结果表明，所提出的制冷和供暖改造机制以及进度控制的实施可以将 GSHP 功耗降低 63.2%。同时，投资税收抵免 （ITC） 和优惠的零售电价可以将长期平准化能源成本 （LCOE） 降低至 0.077 美元/千瓦时。所提系统中 COPTLR 和 SCOPTLR 的最小值分别为 0.492 和 0.483。该研究充分展示了所设计的太阳能地热系统的优势，并突出了所提出的性能指标的有效性。