The idea of solar panels producing electricity in the middle of the night seems entirely preposterous. After all, the reason solar panels are even called solar panels is because it is a material which relies on the sun to function.
Wait a minute, says UC Davis professor Jeremy Munday. He’s recently authored a concept paper which claims such a nighttime solar panel can crank out 50 watts of electricity under ideal night conditions. That’s about 15% as much power as a normal solar panel during ideal daylight.
Even though that may sound like a small amount of electricity, when you consider coupling many panels together into an around the clock array, it creates a compelling option to sustainably balance out the power grid.
“You have to use different materials” says Munday, “but the physics is the same.”
Regular solar cells make electricity by absorbing sunlight, which creates voltage and current. The nighttime solar panel, or “anti” solar panel works with the same physics as a normal photovoltaic cell, but the process to create electricity is reversed. It relies on a device called a thermoradiative cell (TRC).
TRCs have a unique property to them. If the TRC is hotter than its surroundings, it can give off more photons than it absorbs. TRCs have been successfully used by researchers to capture and convert normally wasted engine heat into electricity. In a TRC light gets emitted instead of absorbed and the current and voltage simply go in the opposite direction.
Researchers are currently working on prototypes for TRC panels that work at night. We’d love to see conventional solar panels integrated with TRCs to offer day/night electricity production capabilities. The future is exciting, we’re glad you’re a part of it with us.
Last modified: February 7, 2020