Performance Comparison of a BIPV Roofing Tile System in Two Mounting Configurations

This paper examines the performance of a building integrated photovoltaic (BIPV) roofing system commonly available to residential markets. In particular polycrystalline Si PV roofing tiles were integrated with concrete roofing tiles in two mounting configurations being used by roofing contractors. In the first configuration the tiles were directly mounted to the roof sheeting allowing little to no airflow under the PV modules. In the second configuration furring strips were attached to the roof deck to create a counter-batten system to which the roofing and PV tiles mount. This counter-batten system provides an air gap between the roof deck and the PV/concrete tiles which allows for convective cooling. A complete data acquisition system was applied to both mounting configurations and they were monitored for a summer period in Golden, Colorado. A performance comparison is presented for the systems while both are gauged against free-standing rack-mounted polycrystalline Si PV modules. As expected, modules mounted directly to the deck operated at higher temperatures and produced less power than those on a counter-batten system while both systems operated at higher temperatures than rack-mounted modules.