Ernie Willson wrote:
....
It is true that the old incandescent bulbs do provide heat, however,
like resistance heat, they are very inefficient. IIRC a good heat pump
will provide about four to six times as much heat as a resistance heater
or incandescent for the same power consumption.
....
While I'm not going to say lighting is the ideal way to heat, and
there's truth to the heat pump, it achieves such efficiencies only when
source temperatures are relatively high whereas the resistance heater is
the same irregardless.

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