Thermal Influence of Adhesive-mounted PV on Underlying Roof

N. Shukla
Fraunhofer Center for Sustainable Energy Systems CSE,
United States

Keywords: BIPV, building physics, adhesive-mounted PV, building energy analysis

Summary:

The adhesive-mounted rooftop Photovoltaic (PV) system has drawn attention in recent years because of its potential to significantly reduce the cost of PV installation on the building roofs. In a typical adhesive-mounted PV system, a PV module is adhered directly to the roof shingle using special adhesives. This raises concern about the undesirable heat build-up under the module, which may translate into higher daily peak temperature of the roof shingles, leading to reduced life of these roof elements. The objective of this study was to investigate whether the adhesive-applied PV system will cause a heat build-up under the module. Two identical test hut structures with 2.44 m x 3.66 m footprint and 4:12 slope south facing roof were built in hot desert climate of Albuquerque, NM. Adhesive-applied PV modules were installed on one of the roofs, while the other roof served as a reference for comparison. During the summer period testing, daily peak shingle temperature on the PV test structure was observed to be almost 5–15°C cooler compared to the reference structure. Average daily peak heat flow through roof deck was almost 50% lower than the reference.