> the APL team achieved nearly 100% improvement in efficiency over traditional thermoelectric materials at room temperature

Peltier effect refrigeration has very low efficiencies (5%) so while this is an amazing accomplishment it will not replace other more mechanical cooling methods.

For sure this doesn't replace mechanical cooling.

But efficiency is extremely important in this context, not just for saving energy, but because the inefficiency manifests as heat generated, which undermines the intended refrigeration. So as far as Peltiers go, a doubling of efficiency is like a 3x ~ 4x improvement in effectiveness. Peltiers are already used for cooling in some contexts (eg. cooling CCDs) and this greatly grows the envelope for where they can be effectively employed.

I'm not sure why we would want to replace mechanical systems. A portable AC unit with 10,000 BTUs uses ~650wh these days, and it'll turn a 50m^2 apartment into an icebox. That's not much more than a flagship GPU pulls. This is also about the least efficient class of aircon you can get.

Sure less energy usage is always better, and if we could get the same out of mere single digit wh power draws that would be cool. But I don't think thermoelectrics are ever going to get us there.

IIRC there is an application in solar panels where thermo electric cooling could play a role if we could get the efficiency just slightly higher.

I’m not sure what they mean by “traditional materials” here, but from their paper the COP is in the range of 1.3 - 6.8 depending on heat load which is similar to a modern household refrigerator. So yeah, it really does seem to be good enough to replace mechanical cooling.

The paper also references a Samsung hybrid refrigerator that already uses a thermoelectric device to improve efficiency (probably by letting the compressor operate in a more efficient mode most of the time).

According to the paper Samsung uses a bulk TEC device with a COP of 1.2 - 3 depending on heat load. That’s already fairly close to mechanical cooling. If it wasn’t it wouldn’t have made sense for Samsung to use it in a refrigerator whose whole selling point is efficiency.

I mean, clearly the 100% improvement is for the high heat load COP relative to that Samsung device, right? From 3 to 6.. and I think 6 is better than most commercially viable mechanical cooling solutions, no?