Upsetting the balance beam: System integrative photovoltaics as purposeful manipulation of energy demand and microclimate in the built environment

Knowledge of the local solar resource and the goals of the desired structure can inform the process for energy conversion systems to be integrated into building systems in a purposeful manner for the lifetime of use-coined System Integrative Photovoltaics (SIPV). We show that the original Building Integrated Photovoltaic (BIPV) concept has become brittle with lack of exploration. The apparent goals of BIPV are to reduce fixed costs of installation and materials for photovoltaic modules by integrating them into the building envelope, but the mechanism or process for this integration has been largely absent. This strategy has led to a misinterpretation that one may simply replace the façade with PV elements. From a SIPV design criteria, solar technology implementation can enhance sustainable building practices by acknowledged boundaries for thermal exchange in addition to power conversion. The resources are available to address the system-surrounding interface via microclimate modification, which affects performance of both the PV and the envelope. Here, new design and engineering cases are compared for the next wave of photovoltaic integration with the built environment. Four studies are contrasted for residential integrative PV systems. These include the MorningStar Pennsylvania from the 2007 Solar Decathlon; Kieren Timberlake Architects' (KTA) Cellophane House installation for the MOMA in 2009; Darmstadt's SurPLUS house for the 2009 Solar Decathlon; and finally Penn State's Natural Fusion Green Roof Integrated Photovoltaic (GRIPV) approach for the 2009 Solar Decathlon.