Solar cells produce electricity at night: production has doubled now

Scientists at Stanford University have solar modules Built, which also supplies electricity at night. It achieves much better values ​​than prototypes – although the amounts of electricity are still low, it is sufficient for some applications.

It is a well-known fact that solar cells absorb light during the day – this is how they generate electricity. On the other hand, it emits light at night – albeit invisible to humans in the infrared spectrum. As a result, the modules do not simply go to the level of ambient air temperature and corresponding heat compensation occurs, but instead cool a little more.

This temperature gradient between the solar module and the surrounding air can be used by the thermoelectric effect. With some additional technology, the unit can be used to generate some electricity. However, the return is low compared to what the system can do during the day. The researchers’ system achieves 50 milliwatts per square metre.

no wear and tear

However, this is already double what prototypes of a similar technology were produced a few years ago. And developers want better results in the future. However, there are clear limits to the process: even in theory, at best, one to two watts per square meter can be achieved.

Of course, this is not power generation that can be used to supply the public grid. However, smaller applications can certainly be made around solar cells – whether that’s in the form of lighting with LEDs or powering various measuring instruments for which you’ll have to plug in rechargeable batteries to bridge the night. In contrast, thermoelectric elements also do not wear out, so they always give the same performance without any problems until the solar module reaches the end of its life cycle.

See also: Electricity in the dark: Researchers develop a “solar cell” at night


Outer space, light, night sky, night
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