APOLLO · A Proactive Approach to the Recovery and Recycling of Photovoltaic Modules

Current recycling practices for Photovoltaic (PV) waste modules are unrefined and recover low volume and low value materials. To be economical and sustainable the recycling of PV waste needs to efficiently recover all of the material constituents at a quality suitable for the reuse in new PVs, with minimal impact. APOLLO will create a circular approach to link legacy recycling, future production and future recycling. A pilot line will be demonstrated and used to process an input of 40 tonnes of PV waste which will be recycled, resulting in enough reclaimed materials for 1 tonne of remanufactured silicon and 30 exemplar PV modules. Incoming modules will be streamed by glass composition, enabling batch recovery of high-quality glass, to be used for new solar-grade glass. A novel continuous ‘sonification’ technique, (ultrasonically excited etchant) will rapidly separate silicon, silver, copper and other metals in a sequence along a pipe-based process. Used liquid etchants will be recycled in a closed loop resulting in low waste, small footprint. Further, recovered silicon will be refined to a purity suitable for new PV-grade ingot growth. The objective is to deliver purified silicon with a minimum purity of 99.9999%. Multiple innovations increase the percentage weight recovery from 18% to 93%. APOLLO will prove the suitability of the recycled silicon by growing new ingots, manufacturing solar cells and then new PV modules. 20 PERC-based modules, 10 Tandem modules and 30sqm of single junction perovskite cells will be made. These modules will incorporate new designs, materials and manufacturing methods, and be designed for disassembly and recycling. Blockchain-based Digital Product Passports (DPPs) for PV will be designed and implemented as well as an online marketplace for reused, remanufactured and/or recycled PV components. DPPs provide secure and trustworthy data for the life of the product and aid recycling by supplying material, hazards and history on request.