Infrared: A Renewable Energy Source? Infrared energy emitted from the Earth into space may be potentially harnessed as a renewable energy source in the future.
Physicists at the Harvard School of Engineering and Applied Sciences (SEAS) proposed a device that would resemble a photovoltaic solar panel. But instead of capturing incoming visible light, it would generate electric power by harvesting energy from Earth’s infrared emissions into outer space.
The researchers proposed two possible designs (one macro, one nano) for an emissive energy harvester (EEH) to harness such infrared emissions.
The first design, a thermal EEH, would generate electricity by drawing the heat of surface ambient air through a cold plate that could radiate the energy into the atmosphere, with the flow of heat generating work.
Keeping the cold plate cooler than the ambient temperature would be difficult, but this device illustrates the general principle: differences in temperature generate work, the researchers said.
The alternative design uses rectifying antennas, or rectennas, warmed by ambient air as part of a circuit that generates direct current using temperature differences between electrical components.
“Today’s technology is not sufficient to make an efficient, cost-effective, optoelectronic EEH, but we have described a number of paths that could plausibly lead there over time,” the researchers wrote.
“Now that we understand the constraints and specifications we are in a good position to work on engineering a solution.”