4 ms·

Doubles efficiency? From what I understand, the efficiency was pretty lousy to start with: https://www.youtube.com/watch?v=CnMRePtHMZY https://www.youtube.com/w

Doubles efficiency? From what I understand, the efficiency was pretty lousy to start with: https://www.youtube.com/watch?v=CnMRePtHMZY https://www.youtube.com/watch?v=CnMRePtHMZY Aren't there theoretical limits to this sort of cooling too? But, if this innovation causes Technology Connections to make yet another heat pumps video, I'm all for it.

jfengel 1y ago
Efficiency is pretty lousy. But sometimes you don't want to lug around a compressor, like inside a portable device (such as a food cooler, portable computer, or even a prosthetic limb). In that case inefficient is often better than nothing.
- bradfa 1y ago
  But also if this is an indication that more research effort is going into this because of breakthroughs, that’s a good thing. Double the efficiency a few more times and pretty soon it could be competitive in many uses. Solar panels used to be horrible at efficiency. Now they’re pretty amazing and extremely competitive in the power generation market. It, similarly, took a few decades of these kinds of efficiency improvements to get there.
  - criemen 1y ago
    > Solar panels used to be horrible at efficiency. Now they’re pretty amazing and extremely competitive in the power generation market. To be fair, in my understanding economies of scale kicked in _hard_ for solar, making it much cheaper to produce single panels, moreso than making each individual panel more efficient.
- AngryData 1y ago
  Ehh, we have managed to make pretty tiny compressors these days. Small enough that people are putting AC units into cosplay costumes. You can also buy compressor based ice coolers now that are lighter and last longer than one full of ice or one full of ice and peltier coolers.
  - foxyv 1y ago
    A lot of them are small enough to power with a single Solar panel too. The ice chest ones usually use about 48 watts.
  - Nvorzula 1y ago
    I'll throw in my own niche usecase for thermoelectric - deep sky imaging. I do astrophotography as a hobby (taking pictures of galaxies/nebulae/etc). This involves doing long, multi-minute, exposures repeatedly all night long. The heat generated from such long exposures produces what are called "hot pixels" - noise generated by heat disrupting the electronics. To combat this, dedicated deep sky imaging cameras run a thermoelectric cooler to bring the sensor to sub-zero temperatures. These sensors tend to be about 23.5×15.7mm in size. Niche, sure. But I saw an opportunity to bring up an aspect of my own life where I sincerely do not think even the smallest compressors would be practical. Plus, the lack of moving parts in thermoelectric is very attractive.
gcanyon 1y ago
HA! I know we're not supposed to do "me too" posts, but literally the second I saw the headline I was thinking of the Technology Connections videos I've seen comparing thermoelectric to <anything else> and how inefficient it is in comparison. My memory is more than 2x, but I figure it's worth checking the videos to be sure before making an ass of myself. But before that I figure it's worth it to check the comments already to see what people are thinking. And of course, your comment is at the top of the list. Someone should code an "HN TC poster-bot" that scans headlines for topic matches and just immediately posts the relevant TC video. All of which to say, TC is awesome and everyone should check it out.
- hnuser123456 1y ago
  Well, the thing is, heat pumps/compressors can be more than 100% efficient by using phase change, they can be "200-300% efficient". It's not clear that TEC will be able to do that, and they're currently around 5-10% efficiency. They're good for active cooling phone holders, maybe a chilling cupholder or stuff like that. Novelty items where you have USB power and want to cool something maybe 10-20 degrees below ambient and can have a heatsink/fan on the hot side. You can stack them for a bigger delta T, but the efficiency drops even more, and you end up needing to use increasingly smaller modules on the cold side, so only good if you need to get something small and well-insulted down to very cold temps, not active cooling.
  - sandworm101 1y ago
    10% efficient, without working fluids or moving parts, can be epicly more practical than 300% with those things. In very small or hard to reach places, peltiers are often only real option.
    - rcxdude 1y ago
      Yeah, pretty much. I haven't seen a compressor-based cooler that's a few cm across. But it's not something that will replace AC, fridges, or freezers, which is where they get hyped in popular media. It's a niche technology for niche applications.
thinkcontext 1y ago
There are current applications for solid state cooling. Why wouldn't you welcome those applications being more efficient?

jfengel 1y ago

Efficiency is pretty lousy. But sometimes you don't want to lug around a compressor, like inside a portable device (such as a food cooler, portable computer, or even a prosthetic limb). In that case inefficient is often better than nothing.

bradfa 1y ago
But also if this is an indication that more research effort is going into this because of breakthroughs, that’s a good thing. Double the efficiency a few more times and pretty soon it could be competitive in many uses. Solar panels used to be horrible at efficiency. Now they’re pretty amazing and extremely competitive in the power generation market. It, similarly, took a few decades of these kinds of efficiency improvements to get there.
- criemen 1y ago
  > Solar panels used to be horrible at efficiency. Now they’re pretty amazing and extremely competitive in the power generation market. To be fair, in my understanding economies of scale kicked in _hard_ for solar, making it much cheaper to produce single panels, moreso than making each individual panel more efficient.
AngryData 1y ago
Ehh, we have managed to make pretty tiny compressors these days. Small enough that people are putting AC units into cosplay costumes. You can also buy compressor based ice coolers now that are lighter and last longer than one full of ice or one full of ice and peltier coolers.
- foxyv 1y ago
  A lot of them are small enough to power with a single Solar panel too. The ice chest ones usually use about 48 watts.
- Nvorzula 1y ago
  I'll throw in my own niche usecase for thermoelectric - deep sky imaging. I do astrophotography as a hobby (taking pictures of galaxies/nebulae/etc). This involves doing long, multi-minute, exposures repeatedly all night long. The heat generated from such long exposures produces what are called "hot pixels" - noise generated by heat disrupting the electronics. To combat this, dedicated deep sky imaging cameras run a thermoelectric cooler to bring the sensor to sub-zero temperatures. These sensors tend to be about 23.5×15.7mm in size. Niche, sure. But I saw an opportunity to bring up an aspect of my own life where I sincerely do not think even the smallest compressors would be practical. Plus, the lack of moving parts in thermoelectric is very attractive.

gcanyon 1y ago

HA! I know we're not supposed to do "me too" posts, but literally the second I saw the headline I was thinking of the Technology Connections videos I've seen comparing thermoelectric to <anything else> and how inefficient it is in comparison. My memory is more than 2x, but I figure it's worth checking the videos to be sure before making an ass of myself. But before that I figure it's worth it to check the comments already to see what people are thinking. And of course, your comment is at the top of the list. Someone should code an "HN TC poster-bot" that scans headlines for topic matches and just immediately posts the relevant TC video. All of which to say, TC is awesome and everyone should check it out.

hnuser123456 1y ago
Well, the thing is, heat pumps/compressors can be more than 100% efficient by using phase change, they can be "200-300% efficient". It's not clear that TEC will be able to do that, and they're currently around 5-10% efficiency. They're good for active cooling phone holders, maybe a chilling cupholder or stuff like that. Novelty items where you have USB power and want to cool something maybe 10-20 degrees below ambient and can have a heatsink/fan on the hot side. You can stack them for a bigger delta T, but the efficiency drops even more, and you end up needing to use increasingly smaller modules on the cold side, so only good if you need to get something small and well-insulted down to very cold temps, not active cooling.
- sandworm101 1y ago
  10% efficient, without working fluids or moving parts, can be epicly more practical than 300% with those things. In very small or hard to reach places, peltiers are often only real option.
  - rcxdude 1y ago
    Yeah, pretty much. I haven't seen a compressor-based cooler that's a few cm across. But it's not something that will replace AC, fridges, or freezers, which is where they get hyped in popular media. It's a niche technology for niche applications.

thinkcontext 1y ago

There are current applications for solid state cooling. Why wouldn't you welcome those applications being more efficient?