[NathanielK]

> because they don't actually generate heat Heatpumps still do use electricity(or other power), and all that electricity also ends up as heat. It's why heatpumps have higher CoP than the same system as a refrigeration cycle.

> Thermodynamics would not take kindly to you having a >99.999...% efficient anything

Well the cogen gas powerplants here can produce 50kWh of electricity from burning 100kWh of natural gas. I can use 50kWh of electricity to put 200kWh of heat into my house with a heatpump.

Seems like a good deal to me, and I think carnot would be fine with that.