Harvard Scientists are working on a new renewable energy system that can harvest the power from the earth’s infrared energy. Our planet is constantly releasing hundreds of millions of gigawatts of infrared radiation into space, and now physicists at the Harvard School of Engineering and Applied Sciences (SEAS) envision two devices that could capture it. The research team proposed a pair of devices similar to photovoltaic power systems – but instead of capturing incoming visible light, the devices would generate direct current electrical power by emitting infrared light.
It might seem unfathomable to produce energy by releasing energy, but as it turns out the power is real, if a bit modest. The principal investigator Federico Capasso and his team developed two devices to utilize infrared radiation, which normally imbues gasses with energy to produce heat.
The first would be analogous to a solar thermal power generator, which normally takes the solar energy to heat up water and produce steam energy. The Harvard device employs a similar principle using a “hot plate” that heats up to the temperature of the Earth. Above it there would be a cold plate that efficiently radiates heat upwards. Supposedly this simple heat difference could generate a few watts per hour throughout the day and night.
A second proposed device would also utilize temperature difference to generate electricity except on the nano-sized scale. The scientists theorize temperature differences between nanoscale electronic components—such as diodes and antennas—could continuously push current to create a stream of electricity.
The Harvard researchers believe that while the optoelectronic approach has never been used practically, it’s feasible thanks to recent technological developments. These new technologies include advances in plasmonics, small-scale electronics, new materials like graphene, and nanofabrication. As for the low energy production, the scientists believe that their infrared emission systems could be coupled with a normal solar cell to get extra power at night without an extra installation cost.