Quantification of energy savings from dynamic solar radiation regulation strategies in office buildings

•For the first time, we study the impact of independent management of the direct and diffuse solar radiation on total energy consumption.•Solar radiation dynamic range impact-analysis on the primary energy requirement (PER).•Energy savings impact of resolution of solar radiation regulation.•We lay the ground work for specification development of next generation dynamic fenestrations.•We study and propose optimization control strategies.

Traditionally, glazing-specific technologies have been studied at a theoretical or experimental level with the goal of identifying the optimum thermo-optical parameters that the glazing should have in order to provide energy savings. In this work, we focus on quantifying the impact of the direct and diffuse solar radiation components on energy savings for office buildings following a technology-agnostic approach. More specifically, the question to be answered is: “How can independent management of the solar radiation components offset electric lighting, but on the other hand, possibly put additional load requirements on space-heating/cooling, and fans?” We use EnergyPlus to simulate an adiabatic perimeter office space, with typical zone characteristics, under various solar radiation levels. The solar radiation values are derived from an EnergyPlus weather file. We process that original weather file and create new weather files with reduced solar radiation by specific percentages and simulate the same adiabatic office. We only reduce the direct and diffuse solar radiation components of the original weather file in order to study the impact of regulated solar radiation on the zone’s lighting, heating, fans, and cooling primary energy requirement. Second, we perform a dynamic solar radiation regulation analysis on a monthly, daily, and hourly basis. We show that faster regulation response time of the solar radiation leads to higher energy savings. The reference scenarios for the North, East, South, and West-facing zones require a total of 71, 106, 87, and 99 kW h/m2y respectively. An hourly solar radiation regulation can lead to maximum energy savings of 18%, 33%, 37% and 36% for each orientation. Finally, we perform a study that quantifies the impact of potential technological constraints, such as reduced dynamic range and resolution of the solar radiation admittance, on energy savings.