Techno-Economic Comparison of Different Solar Photovoltaic/Thermal (PVT) Absorber Designs for Ground Source Heat Pump (GSHP) Integration
Abstract
This study assesses the performance of a PVT+GSHP system using four different PVT collectors, each with unique design features, for a multi-family building in Stockholm. Thermal performance coefficients are obtained through outdoor testing of each collector under low-temperature conditions, and incorporated into a comprehensive dynamic system model in TRNSYS. The study varies the design and array size of the PVT collectors and evaluates their impact on the techno-economic performance of the system, considering traditional and undersized borehole fields. Technical performance metrics include annual thermal energy output, seasonal performance factor and back-up heater utilization, and economic performance is assessed with total life cycle cost (TLCC). The results show that when integrating PVTs with GSHP systems, lower collector costs should be prioritized over enhanced thermal performance. Despite the finned designs exhibiting a higher thermal yield (up to 10%) this only improves the seasonal performance factor by 0.6% compared to non-finned designs, but can increase TLCC by up to 5.2%.