Challenge to Move from 'One Size Fits All' to PV Modules the Customer Needs: Preprint

Historically, PV companies requested a single qualification test for a single product. As the market has grown, there have been increasing opportunities for companies to differentiate their products while still maintaining high manufacturing volumes of each product. At the same time, as PV is deployed in an increasingly broad range of conditions, modules need to be able to withstand a wide rangeof stresses. In some cases, targeting a specific deployment condition may allow reduction of product cost. Realizing this opportunity will require the ability to confidently predict long-term performance based on accelerated tests and known weather conditions. By working together, the community can most quickly develop tests that identify which products perform well under which conditions. Thispaper discusses some of the challenges of predicting long-term PV performance, including the wide range of stresses that may be encountered, the variability of the stresses from moment to moment, the complexity of some degradation mechanisms, and the dependence of accelerated testing on module geometry. The paper also describes two international projects that deal with location-specificdurability evaluation and long-term module performance.