Assessing the energy performance of solar photovoltaic, thermal and hybrid PVT panels in a building context: A systematic study of the criteria’ definitions and studies parameters

• Criteria for energy performance evaluation of active solar technologies are screened. • Energy criteria for ST, PV and PVT panels are categorised and discussed. • Energy, primary energy and exergy criteria are the most used ones. This study presents a comprehensive analysis of 30 research papers that define criteria for evaluating the energy performance of photovoltaic (PV), solar thermal (ST), and hybrid photovoltaic-thermal (PVT) panels in building integration. A key focus is the simultaneous evaluation of both heat and electricity production, which is a crucial challenge in comparing these technologies. The papers are categorized into four key metrics for combining energy forms: energy, primary energy, exergy, and energy equivalence. Among these, primary energy is the most frequently used, as it converts electricity to heat through location-specific primary energy factors, providing a common way to measure both energy types. Exergy, utilizing the second law of thermodynamics, allows for a more refined assessment by considering the quality of energy forms, unlike the first law which treats all energy as equal. However, variations in exergy analysis can arise due to differences in how studies account for the exergy of incident solar radiation and the chosen reference temperature. Energy equivalence, finally, considers the specific HVAC systems used together with solar panels. Additionally, this study identifies parameters that are frequently highlighted in solar panel comparisons. The highlights of this work provide a nuanced understanding of how PV, ST, and PVT technologies perform under various evaluation criteria, offering clearer guidance for future research and practical applications.