EU scientists record 99.5% sunlight absorption leap for solar towers

Researchers at the University of the Basque Country (EHU), in collaboration with the University of California, San Diego (UCSD), have developed copper cobaltate nanoneedles coated with zinc oxide that achieve an unprecedented 99.5% sunlight absorption. This breakthrough surpasses the previous benchmark set by vertically aligned carbon nanotubes, which absorb about 99% of sunlight but degrade quickly under high temperatures and humidity. The new nanoneedles demonstrate superior optical and thermal stability, making them highly suitable for use in concentrated solar power (CSP) towers, which require ultrablack materials capable of withstanding extreme environmental conditions. CSP technology, unlike conventional photovoltaic systems, stores solar heat as thermal energy by heating molten salts, enabling electricity generation even when sunlight is unavailable. Despite its advantages, CSP has been limited by material challenges and higher costs. The new nanomaterials developed by EHU and tested in high-temperature labs represent a significant step toward more efficient, durable, and reliable solar tower