Power Generation and Visual Comfort Performance of Photovoltaic Toplighting Technologies in Transient Spaces

Abstract

Advances in long-span glazed structures and interest in high-performance building design has proliferated semi-conditioned spaces with large areas of overhead glazing. These spaces are often programmed with intermittent occupation where variability of the indoor climate is an intentional factor of the experience. Technological options for glazed canopy structures have likewise evolved, gaining functions such as power generation which diversifies the benefits of overhead glazing beyond weather protection and daylighting. Here we model the multiple benefits of current and emerging toplighting technologies deployed in the overhead glazing of a train station and compare power generation and visual comfort. A common building integrated photovoltaic system comprised of monocrystalline cells embedded in the interlayer of laminated glazing is compared with a dynamic, tracking solar collector technology that concentrates and largely intercepts direct solar energy but is transmissive to diffuse sky radiation. The concentrating system generates 6% more power annually with a 70% higher peak power production compared to a typical fixed PV system while at times significantly reducing glare.