But it isn't? For e.g. outside sheds (heated to 7°C) the COP can theoretically go up to 27. For solar panels, the highest theoretical efficiency is well below 100% and the bound isn't communicated.

> It also fails to communicate that it's harder to move the heat when it is colder.

For heating that's less the case, but the efficiency of e.g. solar panels also varies depending on the temperature. That's not exclusive for heat pumps (although much more extreme there).

> You could even give it a different name to `void the scary word if you want, just don't call it efficiency because it's not.

Few people know what Coefficient of Performance means. If I give choose a new name, even less people will understand it. I try to either put efficiency in quotation marks or explain the concept, but efficiency maps (in the sense of energy I care about in and out) pretty well.

I think anti-education is too harsh, I'd describe it more as a white lie. It's the same as saying Mac & Linux systems don't get malware or saying in school maths that you can't take the square root of -1.

Wrong, but correct enough for understanding the point and allowing useful reasoning.