Moritz Riede, University of Oxford, Oxford, United Kingdom
Organic photovoltaics (OPV) has developed from a laboratory curiosity some decades ago into a technology that is now being successfully commercialized. Certified power conversion efficiencies are exceeding 20% in the laboratory and first commercial modules have passed the same stringent IEC tests used to evaluate the quality and stability of silicon PV, the incumbent technology. With properties like mechanical flexibility and a weight of 2kg/m² as well as tunable absorption/transmission, OPV is in particular suited for the built environment and distributed power generation, and for surfaces standard silicon PV cannot be used on (e.g. curved surfaces, low load bearing constructions, semitransparent windows etc.). These additional markets are estimated to be several TW_p in size. At the same time, first life cycle analysis (LCA) data of OPV modules made on real production equipment confirm the long postulated lower environmental impact, e.g. demonstrated less than 25% of the CO₂e/W_p per OPV module compared to the average silicon PV module, making OPV greener than any other commercial PV technology.
The large majority of R&D in academia has been carried out over the past decades on OPV made via solution-based methods, from the non-scalable spin-coating to scalable methods like slot die coating. Continuous optimisation has led to the recent power conversion world record mentioned above. However, with the exception of Epishine, which focuses on small OPV for powering the internet of things, companies have been struggling to translate this to successful commercial enterprises so far. Large area commercialisation of OPV is – despite the comparable little global R&D capacity – currently led by vacuum-deposition methods. It builds on the same methods which enabled the successful large-scale commercialisation of organic light emitting didoes (OLEDs) replacing the incumbent LCD in many display applications. In this presentation, the state-of-the art vacuum-processed OPV is reviewed as well as challenges and opportunities discussed when rapidly scaling this technology to TW_p.