Quantcast
Environmental News for a Healthier Planet and Life

‘Anti-Solar’ Cells Could Keep the Power Going at Night

Science
‘Anti-Solar’ Cells Could Keep the Power Going at Night
Photovoltaic cells that work at night could generate renewable energy from the heat difference between Earth and space. vencavolrab / iStock / Getty Images Plus

Solar panels that work at night? The idea isn't as far-fetched as it might seem.


A University of California (UC), Davis engineering professor is developing prototypes of an "anti-solar" cell that would work in the opposite way from a typical solar panel. Instead of being cooler than the air and absorbing sunlight, it would be warmer than the air and give off infrared light.

"A regular solar cell generates power by absorbing sunlight, which causes a voltage to appear across the device and for current to flow," the professor, Jeremy Munday, explained in a UC Davis press release. "In these new devices, light is instead emitted and the current and voltage go in the opposite direction, but you still generate power. You have to use different materials, but the physics is the same."

While this might sound high tech, Euronews explained that the principle behind it has been used to cool homes at night for centuries:

You are using the same theory when you open your windows and doors after a hot day to cool down your house. Essentially this form of passive cooling uses the night sky as a massive heat sink, drawing warmth away from the earth once it gets dark.

Munday, who published a concept paper of his idea in the January 2020 issue of ACS Photonics, said that his device could generate around a quarter of the energy a traditional solar panel can during the day — that's up to 50 watts of power per square meter. While less powerful, his device can be used at any time.

"Solar cells are limited in that they can only work during the day, whereas these devices can work 24/7, which is the real advantage," Munday told CNN. "Nobody wants to lose power once the sun sets."

His "thermoradiative cell" would also work during the day if it were pointed away from the sun or otherwise blocked from direct sunlight, the press release explained.

Munday told CNN that the device could be used to achieve carbon neutrality, because it could run on waste heat generated by industry.

"While these panels can produce carbon-free power [...] when attached to waste heat sources, they can also produce carbon-free power by just sitting on your roof, like a solar panel," he said.

Munday is working on prototypes of these cells with the hopes of improving their efficiency and the amount of power they can generate, according to the press release. However, he acknowledged to CNN that traditional solar panels have "decades of development" on his idea.

Munday isn't the only researcher to seek to generate renewable energy from the heat difference between Earth and space. In May of 2019, a team of international researchers announced that it was possible to generate electricity by pointing an infrared semiconductor at the sky.

"The vastness of the universe is a thermodynamic resource," paper author Shanhui Fan said in an American Institute of Physics press release published by EurekAlert! at the time.

On Dec. 21, Jupiter and Saturn will be so closely aligned that they will appear as a "double planet." NASA Jet Propulsion Laboratory / YouTube

The night sky has a special treat in store for stargazers this winter solstice.

Read More Show Less

EcoWatch Daily Newsletter

Rough handling can result in birds becoming injured before slaughter. Courtesy of Mercy for Animals

By Dena Jones

The U.S. Department of Agriculture (USDA) was sued three times this past summer for shirking its responsibility to protect birds from egregious welfare violations and safeguard workers at slaughterhouses from injuries and the spread of the coronavirus.

Read More Show Less

Trending

A view of the Arctic National Wildlife Refuge during Arctic Bird Fest on June 25, 2019. Lisa Hupp / USFWS

By Julia Conley

Conservation campaigners on Thursday accused President Donald Trump of taking a "wrecking ball" to the Arctic National Wildlife Refuge as the White House announced plans to move ahead with the sale of drilling leases in the 19 million-acre coastal preserve, despite widespread, bipartisan opposition to oil and gas extraction there.

Read More Show Less
The Bond Fire, started by a structure fire that extended into nearby vegetation on Thursday, Dec. 3, 2020 in Silverado, CA. Kent Nishimura / Los Angeles Times / Getty Images

Hot, dry and windy conditions fueled a wildfire southeast of Los Angeles Thursday that injured two firefighters and forced 25,000 to flee their homes.

Read More Show Less
Hospital workers evacuate patients from the Feather River Hospital during the Camp Fire on Nov. 8, 2018 in Paradise, California. People in 128 countries have experienced an increased exposure to wildfires, a new Lancet report finds. Justin Sullivan / Getty Images

The climate crisis already has a death toll, and it will get worse if we don't act to reduce emissions.

Read More Show Less