Breakthrough in Indoor Solar Cells Achieves Over 40 Percent Efficiency in Europe

Researchers at the Fraunhofer Institute for Solar Energy Systems ISE have set a new record by developing GaInP-based indoor solar cells with over 40 percent efficiency, ideal for powering Internet of Things (IoT) devices in low-light conditions without external power sources. These innovative photovoltaic cells are designed to convert weak indoor light, as low as 100 lux, into electricity effectively. Dr. Henning Helmers highlighted the significant efficiency advantages of III-V semiconductors, especially under LED lighting. The study, published in Applied Physics Letters, notes that n-doped GaInP cells significantly outperformed p-doped versions due to longer charge carrier lifetimes, enhancing electricity generation in poor light. This advancement stems from collaborative projects supported by Germany’s Federal Ministry for Economic Affairs and Climate Protection, among others, paving the way for energy-autonomous smart technology fueled by ambient light.