Quantifying dynamic solar gains in buildings: Measurement, simulation and data-driven modelling

Solar energy is an essential renewable energy source for buildings, such as electricity generated by building-integrated photovoltaic and both electricity and thermal energy offered by building-integrated photovoltaic-thermal systems. Additionally, the fraction of solar energy that penetrates the building envelope is known as solar gain, which considerably impacts the internal thermal dynamics in most buildings. Therefore, controlling solar gain plays a key role in passive solar design strategies or minimizing heating/cooling loads for buildings, since solar gains are generally preferred during the heating period (e.g., winter) but undesirable for summer. Gauging the dynamics of solar gains in buildings is vital for characterizing indoor thermal dynamics and optimizing solar gain control. However, there is a lack of summaries in the literature on the available approaches to quantifying solar gain dynamics in buildings. Hence, this paper summarizes and reviews three approaches available in the literature for gauging solar gain dynamics: measurement, simulation, and on-site data-driven modelling. Furthermore, the pros and cons of these approaches are summarized and discussed. Additionally, recent studies highlight that integrating basis splines (B-splines) into data-driven modelling of dynamic solar gains has proven to be a promising solution for significantly enhancing the accuracy of solar gain dynamics using limited on-site data.