The benefits of concentrating solar hybrid systems: A unified benchmarking framework

Compact hybrid photovoltaic-concentrating solar thermal (PV-CST) systems have emerged as a promising strategy to enhance solar energy utilization by simultaneously delivering electricity and heat. Despite their potential, their assessment remains challenging due to the lack of consistent metrics capable of capturing the relative value of these distinct energy outputs. To address this gap, we introduce a unified benchmarking framework for hybrid PV-CST systems that explicitly accounts for the relative value of heat to electricity. Within this framework, we introduce the Effective Improvement Range ( EIR ), a novel metric that quantifies the resilience and competitiveness of hybrid configurations under varying heat-to-electricity value ratios. We apply this framework to three spectral-splitting hybrid architectures, named semitransparent-thermal, semitransparent-photovoltaic, and PV-mirror, each evaluated considering four photovoltaic materials (Ge, Si, GaAs, and GaP). The benefit of hybridization is assessed by benchmarking each configuration against its standalone photovoltaic and thermal counterparts, as well as against state-of-the-art reference technologies. Our analysis reveals that each hybrid architecture exhibits a well-defined optimal heat-to-electricity value ratio. Among the designs considered, GaAs-based PV-mirror systems emerge as the most robust and competitive across a broad range of conditions, offering up to 43% performance improvement over market standards. In contrast, semitransparent thermal and photovoltaic architectures yield only marginal benefits, limited to specific operating regimes and locations. These findings highlight that hybrid PV–CST systems evaluated offer modest gains over established technologies, emphasizing the need for rigorous and unified benchmarking frameworks to accurately identify and guide the development of truly competitive hybrid solar systems.