Chinese manufacturer LONGi says it has developed a solar cell with a conversion efficiency of 35.5%, verified by the European Solar Test Installation, a recognised reference laboratory for calibrating photovoltaic devices. The claim matters because it far exceeds the roughly 25% efficiency typical of commercially available solar panels, potentially signalling progress towards more powerful panels — though the gap between record-breaking lab cells and mass-market products remains significant.

The cell uses crystalline silicon-perovskite tandem technology, which LONGi regards as the future of solar power and which theoretically could reach 43% efficiency. This is the company's latest in a series of incremental gains, having previously hit 33.9% in November 2023 and 34.6% in June 2024, and LONGi says it now holds the world record for this specific technology. However, the US Department of Energy's National Renewable Energy Laboratory reportedly built a cell with 39.5% efficiency back in 2022, and specialised cells for niche uses such as satellites can already reach around 50%; the bigger challenge going forward is scaling such high-efficiency cells for affordable mass production.