Solar great, but the sun isn’t there when we need it most. We cannot rely on solar energy, when we need light and power at night. Or can we? Scientists at the University of New South Wales have found a way to use ‘solar at night’ technology to our benefit.
At night, Earth radiates infrared rays into the frigid space – this is the energy our planet has collected throughout the day. Image credit: Kevin Kandlbinder via Wikimedia (CC BY 4.0)
The big problem with solar and wind power is that it’s unpredictable. The wind doesn’t blow and the sun doesn’t shine when we need more energy. At night, for example, our energy needs often increase, because, ironically, the sun goes out and we start to get cold and need light. But that’s when we can get some energy from Earth’s radiant infrared heat.
Basically, the sun heats up the Earth and it charges like a battery. As the sun sets, the Earth begins to give off the heat it accumulated during the day. Scientists in Australia have made a major breakthrough in renewable energy technology by producing electricity using a semiconductor device known as a polarized thermal diode. The device is made from a material found in night vision goggles and, as scientists have demonstrated, can generate electricity from infrared light.
It’s basically nighttime solar energy, because that energy originally came from the sun. While photovoltaics allow us to generate electricity directly from sunlight, heat-sensing diodes generate electricity from objects that emit infrared rays into a colder environment.
Of course, conventional solar panels are actually still much more efficient – heat-emitting diodes can generate about 100,000 times less electricity than the energy supplied by the solar panels. The scientists believe that this result could be greatly improved in the future – it could theoretically produce about a tenth of the capacity of a solar cell.
Dr Michael Nielsen, co-author of the paper, said: “Even if the commercialization of these technologies is far from complete, starting a growing idea is an exciting place to be. become a researcher. By leveraging our knowledge on how to design and optimize solar cells, and by borrowing material from the existing mid-range infrared optical detector community, we hope to make progress. fast in realizing the dream of solar power at night. ”
Scientists are also thinking that this kind of infrared-generated energy could be used to power small devices, like wearable electronics. In that case, the electricity can be generated from the infrared light emitted by the human body. It can eliminate the need for batteries in some devices. However, of course, commercialization and technological improvement will have to be at the forefront before any of that is a real possibility.
The source: UNSW
