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This new solar thermoelectric generator (STEG) traps heat on one side and cools the other, making electricity from the hot-cold gap via the Seebeck effect. Unli

This new solar thermoelectric generator (STEG) traps heat on one side and cools the other, making electricity from the hot-cold gap via the Seebeck effect. Unlike solar panels, which need direct sunlight, STEGs can use ambient heat and scattered light. That’s why they still work in shaded or cloudy areas—any temperature difference can generate power. Today they’re only ~1% efficient (vs. ~20% for solar), but the new design is 15× better than earlier STEGs. They won’t beat solar panels yet, but could be useful in spots where panels underperform.

eden-u4 1y ago
so they are basically using a similar idea to that of a stirling engine in thermoelectric generator or they use a different mechanism to produce energy?
- kalx 1y ago
  They both use heat. But stirling converts mechanically, whereas STEM converts energy to electricity «directly».
  - deleted 1y ago
    [deleted]
- vasco 1y ago
  Two materials (often n-type and p-type semiconductors) are joined at two junctions, one junction is heated and the other cooled. The temperature difference makes charge diffuse from the hot side toward the cold side, and this charge is what turns into the seebeck voltage they describe. It was just very hard to get anything meaningful out of this because you can't easily get such a temperature difference. If you've read of the peltier effect, it's the same thing as this, just in reverse.
blackjack_ 1y ago
I did data collection for a paper looking at the Seebeck effect in magnetic insulators about ~10-15 years ago, and it seemed like everyone in the whole physics department considered spintronics pretty dead. It feels great to see some big promising applications coming out of the field.
- hatenberg 1y ago
  It’s explicitly part of Chinese science and technology strategy to think outside the box and it’s what’s pushing them forward on areas like semiconductors as well. Given the massive advantage in talent they’ve built up while the Us reverts to Drill Baby Drill we know how this ends. Eventually the Us with push for atmospheric dimming to “fix” the negative externalities of their approach which had the nice side effect of degrading solar …. FMl
  - znpy 1y ago
    You’re being downvoted but i don’t think you’re entirely wrong. China has been pursuing some stuff that the western world had essentially abandoned, getting interesting wins (eg: thorium reactors).
    - braiamp 1y ago
      He's wrong in the "why" tho. It's not that they must think outside the box, it's that they _must_ not all focus on a single point of research. I'm pretty sure that they are also pursuing popular research topics, because it would be pretty bad if they fall behind for not doing the obvious.
  - idiomat9000 1y ago
    Competition is great.
  - stuaxo 1y ago
    Solar and batteries will keep getting cheaper, its going to get harder to maintain fossil fuel use under those market conditions.
fulafel 1y ago
PV panels work in shaded or cloudy settings (at reduced power of course).
- namibj 1y ago
  Yeah, I'd expect anything solar thermal to scale worse than current standard n-topcon glass glass PV panels.
- hinkley 1y ago
  What doesn’t work is concentrated PV, due to the scattering.
newswangerd 1y ago
Would it be possible to do both on a single panel? In other words, put photovoltaic cells on the sunny side and thermoelectric generators on the shady side.
- ortusdux 1y ago
  Photovoltaic efficiency drops as the panels overheat. Some have demonstrated active cooling methods that are net energy gain. I wonder if it would be cost effective to use these between the panels and cooling system?
- namibj 1y ago
  No.
IshKebab 1y ago
But do they actually out-perform solar panels in any situation yet?
hinkley 1y ago
Some of the cooling tricks could likely be used on standard PV, since overheating affects efficiency.

eden-u4 1y ago

so they are basically using a similar idea to that of a stirling engine in thermoelectric generator or they use a different mechanism to produce energy?

kalx 1y ago
They both use heat. But stirling converts mechanically, whereas STEM converts energy to electricity «directly».
- deleted 1y ago
  [deleted]
vasco 1y ago
Two materials (often n-type and p-type semiconductors) are joined at two junctions, one junction is heated and the other cooled. The temperature difference makes charge diffuse from the hot side toward the cold side, and this charge is what turns into the seebeck voltage they describe. It was just very hard to get anything meaningful out of this because you can't easily get such a temperature difference. If you've read of the peltier effect, it's the same thing as this, just in reverse.

blackjack_ 1y ago

I did data collection for a paper looking at the Seebeck effect in magnetic insulators about ~10-15 years ago, and it seemed like everyone in the whole physics department considered spintronics pretty dead. It feels great to see some big promising applications coming out of the field.

hatenberg 1y ago
It’s explicitly part of Chinese science and technology strategy to think outside the box and it’s what’s pushing them forward on areas like semiconductors as well. Given the massive advantage in talent they’ve built up while the Us reverts to Drill Baby Drill we know how this ends. Eventually the Us with push for atmospheric dimming to “fix” the negative externalities of their approach which had the nice side effect of degrading solar …. FMl
- znpy 1y ago
  You’re being downvoted but i don’t think you’re entirely wrong. China has been pursuing some stuff that the western world had essentially abandoned, getting interesting wins (eg: thorium reactors).
  - braiamp 1y ago
    He's wrong in the "why" tho. It's not that they must think outside the box, it's that they _must_ not all focus on a single point of research. I'm pretty sure that they are also pursuing popular research topics, because it would be pretty bad if they fall behind for not doing the obvious.
- idiomat9000 1y ago
  Competition is great.
- stuaxo 1y ago
  Solar and batteries will keep getting cheaper, its going to get harder to maintain fossil fuel use under those market conditions.

fulafel 1y ago

PV panels work in shaded or cloudy settings (at reduced power of course).

namibj 1y ago
Yeah, I'd expect anything solar thermal to scale worse than current standard n-topcon glass glass PV panels.
hinkley 1y ago
What doesn’t work is concentrated PV, due to the scattering.

newswangerd 1y ago

Would it be possible to do both on a single panel? In other words, put photovoltaic cells on the sunny side and thermoelectric generators on the shady side.

ortusdux 1y ago
Photovoltaic efficiency drops as the panels overheat. Some have demonstrated active cooling methods that are net energy gain. I wonder if it would be cost effective to use these between the panels and cooling system?
namibj 1y ago
No.

IshKebab 1y ago

But do they actually out-perform solar panels in any situation yet?

hinkley 1y ago

Some of the cooling tricks could likely be used on standard PV, since overheating affects efficiency.