4 ms·

There are lots of resistive heaters out there. In areas where it gets cold only one day a year, it's the preferred option. They are also used as "emergency he

There are lots of resistive heaters out there. In areas where it gets cold only one day a year, it's the preferred option. They are also used as "emergency heat" for heat pump systems, again for the 1 day a year it's below -17F or whatever. These are absolutely no more efficient than cranking out some renders on your GPU. If you plug a computer into electricity and it draws 1000W, the room gets 1000W of heat. If you plug a space heater into electricity and it draws 1000W, the room gets 1000W of heat. Computers cost thousands of dollars, a 1000W space heater costs $9.99. To answer the OP's original question, the reason that resistive heating is used for space heating is because the heater itself is cheap. A GPU burning power to heat and do computational work is 100x more expensive for the heat output. If you have $1000 to spend on heating, you just get a heat pump or a real furnace. The reason that people choose inefficient heaters is for the lower capital cost. Let's say that 1 day a year, you need heat. Getting 2kW of heat for 24 hours will cost $20 once to buy the heater, and $15 in electricity each time you use it for the 30 times over the 30 year life of your house, so you're spending $470. Meanwhile, if you wanted to be 3x more efficient and go with a heat pump in that room, you're paying at least $1000 for the heat pump and installation, but only $150 for the electricity. You come out behind even though you saved a ton of energy. Meanwhile if you're heating every day for 3 months in the winter, you wouldn't want to be anywhere near resistive heating, because the higher energy costs add up almost instantly. TL;DR: the economics of resistive heating don't favor initial capital outlay that would be required to make them do useful computations while heating. People use resistive heating for "an emergency" and don't want to pay a lot of money for something they never use.

ProfessorLayton 3y ago
Even if capital costs weren't a factor, space heaters make a lot of sense in very common situations involving heating a particular area. It doesn't matter if heat pumps are 3-4x more efficient if one has to heat up 6x-8x the area instead of a small room that's currently being occupied (i.e. a home office).
- jrockway 3y ago
  Yup, very true. Something else I thought of is that if you are a landlord paying the capital costs, but your tenant pays the electricity bill, then you're incentivized to pick the cheapest heating system, not the most efficient one. This factor probably makes resistive heating more widespread than it should be.

ProfessorLayton 3y ago

Even if capital costs weren't a factor, space heaters make a lot of sense in very common situations involving heating a particular area. It doesn't matter if heat pumps are 3-4x more efficient if one has to heat up 6x-8x the area instead of a small room that's currently being occupied (i.e. a home office).

jrockway 3y ago
Yup, very true. Something else I thought of is that if you are a landlord paying the capital costs, but your tenant pays the electricity bill, then you're incentivized to pick the cheapest heating system, not the most efficient one. This factor probably makes resistive heating more widespread than it should be.