[bulrush]

This is an interesting device as waste heat is pretty common: on your car, on your roof in summer, on lots of places in the summer, on AC coils, and more. It would be nice if this would be converted to a reasonably priced consumer device.

I've been hearing about this tech since at least 2012 but the original company folder, to be bought by another company, and that trail has been dead ever since.

https://www.machinedesign.com/mechanical-motion-systems/article/21836996/solidstate-silicon-device-turns-waste-heat-into-electricity

 

[cujet]

Any standard Peltier device can do that. The efficiency of this "rectenna" device is near nil. Engineers have been working on thermoelectric devices for decades and have refined the technology into useful products. However, it's good to know that there are real physical limitations (theoretical limits) with this technology, and there won't (can't) be massive breakthroughs. There are only a few materials that can be employed for this, and none of them do so with good efficiency.

The best we can do is roughly 5-7% efficiency. Far short of using heat to do mechanical work.

https://en.wikipedia.org/wiki/Thermoelectric_cooling

https://en.wikipedia.org/wiki/Thermoelectric_cooling

 

[bulrush]

Any standard Peltier device can do that.

But there are caveats. A Peltier device works only because there is a difference between the hot and cold side of the device. So for efficiency, the cool side must be kept very cold, which is not easily done in a hot environment. I've done the experiments myself and so has several other people on Youtube. A Peltier device technically works, but not very well. It is a fun experiment but is not a competitor to current power generation technologies like a gas powered plant.

 

[KLF]

https://hawu.pro/projekti/hawu-sahkokamiina-projekti/

These guys basically figured out how to implement bunch of peltiers in a portable stove. So you can charge your phone while cooking dinner