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by torpfactory 2250 days ago
They even beat natural gas on operating cost for many installs these days:

Gas Furnace: 1 Therm = 29.3kWh, Cost $1.5 (at least where I live), Furnace efficiency = 95%. Cost per kWh heat delivered = $0.053.

Heat Pump (COP=5, EER=17): 1 kWh = $0.14, COP =5, Cost per kWh heat delivered = $0.028.

Heat pumps are quite a bit more expensive to install though.

1 comments

That depends on the cost of electricity, which varies widely across the continent. I ran the numbers a few years ago for central Ontario (napkin math), and natural gas was 2x or 4x the cost (I can't remember). Anyway, definitely not worth it, especially since it falls back to pure electric heat when it can't keep up. And the house is heated with NG anyway, no point in making that energy transfer even less efficient.

(NG fireplace heats the air, air heats the hybrid water heater coils, which heats the water via refrigerant and a noisy compressor. Instead of NG just heating the water directly.)