Experimental device generates electricity from the cold of space
The device created by Stanford University researchers has a similar optoelectronic system to that used in solar panels. However, solar panels need sunlight to generate electricity. The experimental device, instead of using radiation coming from the sun, uses radiation coming from the Earth.
The obvious róThe difference is that the researchers’ invention móhead to function at night, making it a potential source ofódłem of renewable energy, whichóre could operate around the clock. What’s more, the device is independent of the condition of theóin the weather.
The results of the scientists’ work were published in a recent issue of „Applied Physics Letters”.
– The vastness of the universe is a thermodynamic resource,” said article author Shanhui Fan. – As far as optoelectronic physics is concerned, there is really a very beautiful symmetry between the acquisition of incoming radiation and the acquisition of outgoing radiation, he added.
As opposed to using energy coming into the planet, as normal solar cells do, the experimental device allows electricity to be harvested as heat leaves the Earth’s surface. Current technology does not allow efficient capture of electricity in this wayób, but this may change in the future.
– The amount of power we can generate in this experiment is currently well below the theoretical limit, said Masashi Ono, coópublication author.
In experiments, researchers managed to generate 64 nanowatts per square meter. It’s a small amount of energy, but an important proofód supporting the very concept of the device. This allows the technology to be improved and refined, if only through quantum modifications of the optoelectronic properties of the materials usedów.
The infrared-responsive photodiodes mounted in the device work, so to speak „back”. When photons in the form of infrared radiation, które known róalso as thermal radiation, leave the system, a small amount of energy is generated. In this wayób experimental system uses what scientists call a „effect of negative illumination” – That is, the flow of outgoing radiation as heat escapes from Earth back into space. The configuration used in the device uses póinfrared conductor directed into the sky to convert this flow into electricity.
Calculations made after the photodiode generated electricity showed that, given the effect of theóatmospheric, the current device can theoretically generate almost 4 watts per square meter. This is roughly a million times more than the electricity generated during the experimentów. For leekównania today’s solar panels generate 100 to 200 watts ofów per square meter.
Experiments have shown that this type of device is a promising technology. But the same principle can be used to recover heat from machines, although there is still a long way to go. Currently, scientists are focusing on improving the performance of their device.