Façade-integrated photovoltaics: a life cycle and performance assessment case study

• Published in: Progress in photovoltaics Vol. 20; no. 8; pp. 975 - 990
• Main Authors: Perez, Marc J. R., Fthenakis, Vasilis, Kim, Hyung-Chul, Pereira, Anthony O.
• Format: Journal Article
• Language: English
• Published: Chichester, UK John Wiley & Sons, Ltd 01.12.2012; Wiley; Wiley Subscription Services, Inc
• Subjects: Applied sciences; BIPV; building integrated; CED; Energy; Equipments, installations and applications; Exact sciences and technology; facade PV; façade PV; LCA; life cycle assessment; Natural energy; Photovoltaic conversion; Solar cells. Photoelectrochemical cells; Solar energy; New York City; Performance evaluation; CED; Building integrated photovoltaics; Photovoltaic system; Energy input; LCA; Cladding; Single crystal; Low energy; Case study; Life cycle; BIPV; Electrical network; Database; Irradiation; Concrete; Silicon; façade PV; Low-power electronics; Inventory; Wafer; building integrated; life cycle assessment
• ISSN: 1062-7995; 1099-159X
• DOI: 10.1002/pip.1167

ABSTRACT The Solaire Building has the first façade building‐integrated photovoltaic (BIPV) array in New York City. This paper presents the life cycle impacts of the Solaire BIPV and extrapolates its performance to other façade systems. Engineering diagrams, detailed material inventories and 5 years of irradiation and actual performance data in 15‐min intervals offer insights into current BIPV construction and performance. The Solaire BIPV employs waste‐stream monocrystalline silicon wafers. Correspondingly, zero energy input was allocated to this BIPV from wafer production, resulting to a very low energy payback time (EPBT) and global warming potential burden (0.8 years and −10.2 g CO2/kWh, respectively). A negative EPBT results from subtracting the impact of the thermally and structurally equivalent concrete and brick wall that the BIPV array replaced. Data from current photovoltaic‐dedicated Si wafer supply were also used; these resulted with an EPBT of 3.8 years and a global warming potential of 61 g CO2/kWh. The performance ratio and EPBT of the Solaire system were compared with those in the International Energy Agency Photovoltaic Power Systems Task 2 inventory database. The drawback of façade BIPV is its vertical orientation, receiving lower incident irradiation than rooftop and ground installations. Nevertheless, BIPV offers two main advantages over such installations: it does not require any ‘virgin’ land for its operation, and it replaces structural units, thus avoiding the cost, embodied energy and corresponding emissions related to those. We detail herein how the replacement of traditional cladding materials can offset the performance drawback of BIPV, in terms of environmental burden and EPBT. Copyright © 2012 John Wiley & Sons, Ltd. A performance and environmental characterization of a prototypical curtain wall BIPV array on the Solaire building in New York City yielded further insights into the benefits of building‐integrated applications. A novel approach was used to appraise the material inventory comprising the BIPV to account for the façade cladding that the array entirely replaces. The array employs recycled Si wafers and as such the Energy Payback Time and Global Warming Potential were significantly lower than for other PV systems.