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A techno-economic analysis by researchers at the National Renewable Energy Laboratory (NREL) has shown that perovskite-silicon tandem solar modules could compete on cost with traditional photovoltaic panels. Production costs for US-made tandem products range from $0.29 to $0.42 per W, with module efficiencies ranging from 25% to 30%. Photovoltaic modules based on perovskite-silicon tandem solar cells could be produced in the United States at a minimum sustainable price of $0.35/W, according to a techno-economic analysis conducted by researchers at the U.S. Department of Energys National Renewable Energy Laboratory (NREL). “Our work is based on data we collected last year from equipment manufacturers and material suppliers,” lead author Jacob J. Cordell told pv magazine . “We assumed modules had efficiencies ranging from 25 to 35 percent.” The data were processed using the DCAM detailed cost analysis model, which is a freely available tool developed by NREL itself to build cost models for photovoltaic components and systems. The levelized cost of energy (LCOE) calculation was made assuming tandem efficiencies of up to 35%, lifetimes of 10 to 30 years, and GW-sized factories. The researchers presented a detailed techno-economic analysis of two-terminal (2T) and four-terminal (4T) solar cell architectures and stated that despite their multiple possible design configurations, they face similar manufacturing costs. However, 4T designs may be preferred in the future, as the 2T configuration excludes the use of back contact (BC) devices for the bottom cells. On the other hand, high-efficiency technologies such as BC and heterojunction (HJT) could be the preferred choice for tandem modules, primarily designed to maximize efficiency and power generation. Their analysis, however, also included PERC and TOPCon technologies. The research team found that without the policy incentives provided by the Inflation Reduction Act (IRA) , 25% efficient perovskite silicon solar modules could currently be produced in the United States at $0.359/W for 4T designs and $0.364/W for 2T architectures. They also determined that at 30% efficiency, 4T panels could be manufactured at $0.299/W and 2T modules at $0.303/W. “At 32.5% efficiency, the cost of the 4T module is below our estimated cost for a 22% efficient PERC Si module of $0.285/W,” the report said, noting that at 35% efficiency, the cost would range from $0.257/W to $0.306/W. According to the scientists, the solar glass, backsheets, encapsulation and electron transport layer (ETL) precursors in the perovskite subcell are responsible for the higher cost of tandem modules compared to single-junction products, due to the materials and equipment required. Academics believe these costs could fall further in the near future as they expect silicon cell costs to continue to fall, while perovskite precursors and processing equipment could become more standard at an industrial level. However, according to Cordell, perovskite-silicon tandem modules will only be commercially available if their performance is proven. “Perovskite-based PV plants have recently been commissioned in China, and if data from these installations is made available, we may have interesting information about degradation over time,” he says. “A 2-year trial combined with accelerated testing can help bring this technology closer to market.” Cordell also said its difficult to gauge how much data is needed. Of course, to sell a product you dont necessarily need to increase market share, he said. It may take longer than expected to achieve this goal, as other degradation mechanisms may arise, as were seeing with TOPCon modules in the field right now. NREL scientists added that even taking into account silicon PV manufacturing costs in China, tandem modules may struggle to compete with their single-junction counterparts as the efficiencies of commercially available TOPCon, BC and HJT cells continue to increase and costs continue to fall. “However, our assumptions were based on a type of manufacturing equipment that doesn’t yet exist,” he said. “If tandem module costs are high right now, that doesn’t mean they will be high in two years. A larger perovskite industry can help change this.” Cordell also stressed that tandem modules will also offer an advantage in terms of efficiency per area. “It’s not just about cost per watt,” he said. “You also have to consider the cost savings that come with not having to buy or lease more land. This technology will be developed primarily with large-scale projects, at least initially.” The research work was presented in « Technoeconomic analysis of perovskite/silicon tandem solar modules », published in Joule . |
