SIMPLE BoS: Towards a Multidisciplinary Integration of Photovoltaic Energy in Buildings
The Department of Energy has outlined the SunShot initiative, a plan to increase the adoption of solar energy by making it more cost competitive without requiring subsidies. A key component of this plan is to reduce costs associated with the balance of systems (BoS), which accounts for more than 40 percent of the total installed cost of solar energy systems. Balance of Systems encompasses the reduction of costs derived from all aspects related with the use of solar other than the photovoltaic panels and inverter. A careful understanding of architectural factors that may influence building energy performance is a critical and under-addressed aspect of the problem. The Solar, Installation, Mounting, Production, Labor, and Equipment Balance of System (SIMPLE BoS) project addresses the problem through a multidisciplinary team with emphasis on the integration of solar photovoltaic panels into buildings. Our goal is to produce new photovoltaic module racking and mounting designs, integration strategies, materials and wire management methods aiming to reduce the hardware and associated labor costs by fifty percent. Industry PV installers, university research engineers and students measured the field installation time of current commercial systems on project sites, providing a labor cost benchmark for BoS. Concept designs have been systematically improved through aerodynamic analyses, advanced structural optimization and building systems design integration. According to our estimates, material use reduction, part count reduction, use of commoditized materials, and low cost manufacturing processes have enabled greater than 50% BoS material cost reductions in residential, commercial, and utility designs. Cost-critical aerodynamic and structural aspects have been validated through complete and underway wind tunnel test, computational fluid dynamics (CFD), and finite element analysis (FEA). Current design concepts are introduced as case studies of multidisciplinary collaboration. The implications of multidisciplinary building systems integration is discussed, with reflection on education and practice of architectural design.