Strengthening the case for recycling photovoltaics: An energy payback analysis

The energy payback time (EPBT) of photovoltaic materials when recycled is analyzed. In particular we are interested in under what conditions recycling yields energy payback improvements equivalent to efficiency. The sensitivity to dynamic variables such as composition, efficiency, and recycling rate is also evaluated. We found that, in general, for all technologies, as the efficiency increases, EPBT savings from recycling decreases at a decreasing rate. This result suggests that greater EPBT savings are obtained for low efficiency module recycling, especially when considering framed modules whose aluminum materials make up between 50% and 70% of the embodied energy. Solar PV technologies have exponentially increasing production suggesting an equally growing future waste stream. No policy currently exists in the US for end-of-life management, collection, or recycling. This study demonstrates the potential opportunity for energy savings from recycling and pinpoints metrics that would be important to such a policy.