Net energy and cost benefit of phthalocyanine and heptamethine transparent photovoltaics in commercial buildings

Abstract

There is a growing interest in using transparent organic photovoltaics (TOPVs) to generate on-site electricity and reduce building energy demand. This study evaluates the use of chloroaluminium phthalocyanine and heptamethine-based TOPVs in five types of commercial buildings and four climates in the U.S. The building energy demand is modeled with and without TOPVs, along with the electricity generation from the TOPVs, and the cradle to gate life-cycle cumulative energy demand to manufacture the TOPV modules on glass. The net energy benefit is positive for all five commercial buildings in all four locations meaning that more energy is produced or saved than used in manufacturing TOPVs. The energy payback times for TOPVs are less than other building integrated PV technologies. All commercial buildings save energy, cost, and greenhouse gas emissions with TOPVs, and the best applications depend on the building’s window-wall ratio, occupancy, and usage. In the future, the spectral properties of TOPVs could be tailored to save more cooling and heating energy based on the building’s structure, climate, and energy demand.