[anchpop]

> I imagine that heat is being generated less efficiently than a purpose-built device.

All the heat that comes out of a lightbulb is being generated at 100% efficiency :)

(Although it's likely more expensive to heat your home electrically instead of via natural gas)

[mmcnl]

Heat pumps have higher than 100% efficiency because they extract heat out of air / water. 100% is a very low efficiency for electric heating. Anything lower than 400% is considered below average.

[BlueTemplar]

Sadly, heat pumps are still very rare. (They're much harder to do properly than just electric heating.)