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They operate at up to 400% efficiency and represent serious low hanging fruit for household carbon footprint reduction and the main barrier is education, so no
by voisin 3y ago
They operate at up to 400% efficiency and represent serious low hanging fruit for household carbon footprint reduction and the main barrier is education, so no I don’t think they are overrepresented.
- zabzonk 3y ago400% compared with what? and how?
- AndrewDucker 3y agoThey can shift 4x the amount of heat than the same amount of energy would generate.
- jdlshore 3y agoA resistive electric heater converts 100% of its energy to heat, by essentially wasting it. A natural gas heater converts about 95% of its energy to heat, by burning it. A heat pump converts about 3x its energy to heat, by acting as a sort of reverse air conditioner that’s cold on the outside and warm on the inside.
- thaumasiotes 3y ago400% is probably the ratio of thermal energy released by the heat pump to energy (of whatever kind) used to operate the pump.
- bitshiftfaced 3y agoI take your meaning, and it's a good point. But it's still interesting, even if you swap the framing for "underrepresented outside of hacker news."
- SlightlyLeftPad 3y agoUnfortunately, in California the electricity price is 6x the price of natural gas.
- belthesar 3y agoThis is a fair statement, but it represents an incomplete truth. Quick term run down, then some quick math. COP: Coefficient of Performance. This is a ratio of how much you can augment the temperature for every unit of energy you put in. Your best, most efficient top of the line gas furnace has a COP of 0.98. This means that, for every 1 joule of energy, you're getting 0.98 joules of heat energy. Let's say that, for easy math's sake, you pay $1 per joule for natural gas, so your operational cost for the furnace is $1.02 per joule. Yes, numbers are crazy town, but simple math for simple explanation. A modern bog-standard heat pump has a COP of 4. The operational COP of the heat pump varies depending on the difference in temperature from inside to outside, but the vast majority of the state of California is going to operate at temperatures that can support the COP. Per your statement, electricity is 6x the cost of gas, so we'll say that every joule of energy going into the heat pump costs $6. This puts your operational cost at $1.50 per joule. It's certainly not a "better deal", but the cost delta can't simply be measured by the cost of the energy going into the heating system.
- sokoloff 3y ago> most efficient top of the line gas furnace has a COP of 0.98 That's a steady-state, best-case figure that is almost never achieved in practice. Very long run times and very low temperature operation is required to achieve those figures, and most homes are not setup to create those conditions. I'd not be surprised to learn that most 95+% efficient furnaces run at 90% realized.
- voisin 3y agoThis is super interesting. Do you have a source for this? I don’t doubt it, but I had never thought of it and it doesn’t surprise me that it is a misleading figure to begin with.