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Limits RegistryFraunhofer ISE (Germany) reported a four-junction III-V concentrator cell at 47.6% efficiency under 665x sunlight concentration in May 2022, listed on NREL's Best Research-Cell Efficiency Chart. It remains the highest confirmed photovoltaic efficiency of any kind as of 2026 — note this is a lab concentrator cell, not representative of any deployable rooftop panel (best one-sun silicon cells run closer to 28%).
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Fraunhofer ISE (Germany) reported a four-junction III-V concentrator cell at 47.6% efficiency under 665x sunlight concentration in May 2022, listed on NREL's Best Research-Cell Efficiency Chart. It remains the highest confirmed photovoltaic efficiency of any kind as of 2026 — note this is a lab concentrator cell, not representative of any deployable rooftop panel (best one-sun silicon cells run closer to 28%).
The highest confirmed sunlight-to-electricity conversion efficiency achieved by any photovoltaic cell, under standard reporting conditions, tracked on NREL's Best Research-Cell Efficiency Chart.
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Limits Registry. LR-SOLAR-CELL-EFFICIENCY. Solar cell efficiency (any technology). 2026.