No sun? No problem.
A new thermoelectric device can generate electricity for an LED light bulb even during the blackest night, according to a report by researchers.
The secret is using a phenomenon known as radiative cooling, which happens when surfaces on the ground radiate heat into the atmosphere. This process can make a surface cooler than the air surrounding it, which explains why frost forms on grass even if the air temperature is above freezing.
Researchers say their device is a useful form of renewable energy, especially because lighting demand peaks at night. “Beyond lighting, we believe this could be a broadly enabling approach to power generation suitable for remote locations, and anywhere where power generation at night is needed,” lead author Aaswath Raman, an assistant professor of materials science and engineering at the University of California, Los Angeles, said in a statement.