The life of a PV system: thinking on a 20 year timeline
PES asked Tyler Ogden, Lux Research Inc. to give us his expert viewpoint on the longevity of PV systems. Lux Research is a leading provider of research and advisory services, helping clients drive growth through technology innovation.
Utility-scale systems are now a competitive choice for electricity supply, with bids undercutting conventional sources of generation in some regions, while other regions see competitive subsidy-free deployments. This has largely been the result of declining module costs. Manufacturers have obtained significant economies of scale and have continued to adopt higher efficiency cell technologies.
Meanwhile other players across the supply chain that offer balance of system components and developed projects have reached maturity, contributing to lowering the capital expense of new installations to a point where sub dollar-per-watt systems are now feasible. However, the rate of cost declines has begun to taper off. If solar costs are to continue to drop and maintain the precedent of low-cost renewables, the industry must look elsewhere – must look forward in time.
The standard lifetime for a photovoltaic installation is 20 to 25 years, nearly double the time from when the global solar industry began to mature in early 2010s. The focus has primarily been in reducing dollar-per-watt costs to drive installations to where we are now, what will likely be above 100 GW of annual deployments. Indeed, the vast amount of photovoltaic capacity is only a few years old, providing a limited data source to begin investigating how performance can be improved and costs can drop over the full operational life of a PV system. However, multiple initiatives are underway to address the long-term variables of degradation and maintenance.
Under these market conditions, the U.S.’s Department of Energy declared its cost target of less-than $1.00/W utility-scale solar achieved three years early in 2017, while utility-scale costs in India, Mexico, China, and Egypt have likely been below $1.00/W for longer. Given this early achievement, the Sunshot Initiative has set new goals focused on the cost of generated electricity over the lifetime of a PV system, aiming for $0.03/kWh by 2030. To achieve this, two key areas need to be tackled at once.
Degradation is considered as a constant, a number included in a manufacturer’s linear power warranty that is accepted as is and passed on to cost of electricity calculation. However, the reality is unlikely to be so simple. A number of initiatives are underway to investigate how degradation may be climate dependent, and more significantly what type of materials may decrease climate-dependent degradation.
Led by NREL, the Durable Module Materials (DuraMat) Consortium will pool together resources across four national labs for the development of materials that can improve the durability and lifetime of photovoltaics. The consortium will receive $30 million across five years to support U.S.-based projects in academia and industry. DuraMat falls under the Energy Materials Network with the aim to accelerate the development, characterization, testing, and deployment of novel materials to reduce the LCOE of photovoltaic systems. The support from the Department of Energy (DoE) for the DuraMat consortium highlights the potential high payoff of materials to reach the cost goal of $0.03/kWh.