> The prototype delivers 100% heating at 5°F at double the efficiency, and 70% to 80% heating at -5°F and -10°F
So, 2 EER (2x of resistive heat) at 5F, 1.8 at -5F and 1.6 at -10F? Is that right? Seems awkwardly worded.
So, 2 EER (2x of resistive heat) at 5F, 1.8 at -5F and 1.6 at -10F? Is that right? Seems awkwardly worded.
Yes (or double of previous model as another commentator points out-- hard to say).
> 1.8 at -5F and 1.6 at -10F?
They've not told us the efficiency-- just that it provides 70-80% of nameplate amount of heating at those temperatures.
They could choose the lowest temperature, find it's power input, then fix it at that amount. But at low temperatures the concern is usually less "efficiency" and more "am I going to freeze to death", because in most of the cold areas temperatures aren't usually that cold for that long (though in others it definitely is, and if you're running at 1.6 COP for a significant amount of time, you're better off with more insulation than a heat pump).
A COP of 2 @ 5F isn't a "breakthrough" vs. the first commercially available model I could find numbers for, and a COP of 1.5 at -10F seems implausible:
https://www.nordicghp.com/2017/01/heat-pump-effective-temper...
Honestly though, this press release is so poorly written, I wouldn't trust the numbers match up to anything.