aren’t you still limited by ambient air temp because the hot side of the Peltier needs to be cooled by air anyway?
You can certainly get subambient. Put some electrical current through a Peltier and one side gets cold, and the other side gets hot. Use the cold side to cool your components, and get the heat away from the hot side, and you can make it work.
It can be a bit tricky. The hot side is right next to the cold side and it gets really hot, so if you can’t get the heat away it’ll leak right back over. Peltiers use a lot of power so you need a beefy power supply, and that’ll be another source of heat. Assuming you can figure that all out, you also have to be careful that the cold side doesn’t get too cold or you get condensation. Electrical components tend to not like moisture very much.
I remember people experimented around with it back in early-mid 2000’s. General consensus nowadays seems to be is that it’s not terribly effective and not worth the trouble.
fhqwgads@possumpat.io 2 months ago
No, that’s why the baby fridge works. The peltier TEC in the fridge can produce temperatures below ambient, but generally not below freezing. Computer chip TEC coolers would go farther and push more power through the TEC and do things like water-cooling the hot side instead of a little fan.
The reason they don’t get used anymore more complicated. It’s my understanding that basically TECs have a sort of limit on the amount of heat they can push from the cold side to the hot side, because moving more heat moved means more energy and thus more waste heat. Apparently most modern chips are past that limit. TECs can only move something like 100w of heat - past that and they start to heat themselves up because of waste heat. Modern chips can be like 300w.
Sub ambient cooling also comes with a bunch of issues like condensation, so no one really uses it day to day. Also, chips are run so close to their limits now that cooling like that doesn’t get you nearly the performance difference it once did.