The only heating around here these days is electrical (edit: except for wood stoves, which are usually allowed). Oil isn't allowed, and gas heating doesn't exist. So yes, "no gain" means that the heat output is equivalent to the electricity input (at the low turning point, which is around -20C for my pump - I should qualify that though, it used to be when it was new, but the tech who checked my pump a couple of years ago said it had lost some of its efficiency due to various things including some difficult to remove grime inside, but there still was no point in actually replacing it).
Of course, there's also the installation costs of a heat pump. But it did pay for itself in a reasonably short time. If it hadn't been that efficient it wouldn't have - first, there's the actual price, which is not as much these days as it used to be, but then there's the actual installation by a pro, and I believe that part has only gone up since then.
Is that "no gain" in terms of energy (i.e. heat energy out = electricity in), or financial (i.e. cost of electricity consumed by heat pump = cost of equivalent gas-fired system)?
EDIT: or is it "well-to-wheels" style energy (i.e. primary energy consumed by heat pump = primary energy consumed by gas boiler), or is it CO2 (same emissions)
I suppose this would be true if gas is expensive where you live. It's really cheap here, our heating bill is like $80/mo in the coldest of months for a 3k sq ft house. A heat pump even with the efficiency gains would be on par with that (unless we jumped into solar, which I have considered).
Even without a system that has >100% efficiency (i.e. a heat pump), home heating systems often use a source of heat that is significantly less expensive per watt than electricity. (For example, natural gas.)
Heating with electricity is a profound waste though when natural gas is a fraction of the price. And if you do have to heat with electricity, a heat pump is going to be far better than mere resistance.
An alternative to using heat pumps is to use gas heating. Gas heating lets you achieve >100% "efficiency" relative to electric heating because you don't have to pay the price of converting the gas into electricity.
Natural gas is dirt cheap in most of the U.S., so it does make it hard for heat pumps to compete, especially if electricity is expensive. Just checked my most recent gas bill and I only paid $1.09/therm (plus 7% sales tax and $10 fixed fee).
OTOH if you’re heating with propane or fuel oil, heat pumps are probably a good alternative.
If you're running your electric heating from a natural gas-fuelled power station, which has an efficiency somewhere along the lines of 40% (if you're lucky), then using a heat pump with a COP of 2 means you are heating your home with 80% efficiency. Modern gas central heating systems can be >90% efficient.
Alternatively, if you go by the relative price of electricity compared to natural gas, typically electricity has three times the price for the same amount of energy. In that case, you would need a heat pump with a COP of >2.7 to make heating cheaper than using a gas burner.
Such heat pumps do exist now. The benefit is that if/when the electricity grid transitions to renewables, you are sorted.
That's not true, even if you produce electricity from gas, using a heat pump to heat your home rather than a gas-powered central heating is more efficient.
This is completely false. Gas heating is way, way less efficient than a heat pump. And don't bring up low temperatures, modern heat pumps can have back up resistive heaters and combined use will still be far, far more efficient than gas heat. If you can install geothermal that's better still. Stop spreading fossil fuel industry lies.
In Vermont, we are in our first year with heat pumps. Have a wood stove as backup and supplement when we want to go pantsless mode. The original oil burner is currently turned off, out of commission waiting on some parts. We could go without the wood stove, and have done so for stretches.
We installed Mistubishi Hyperheats, 3 external units, 5 heads. Zero interest financing by installer, for about 21k all in including electrical work. Earlier this year we also did air source hot water heater, for about 4k all in.
We were spoiled by the whole house air conditioning over the summer, and the heating has been performing just fine. It about doubled our electric consumption, but that bill is still less than my oil bill was, before the price of oil nearly doubled.
We're motivated primarily by a desire to minimize fossil fuel consumption, and then to mitigate volatility in fossil fuel markets. With this install we completed electrifying all utilities in the house , and have a rooftop solar array that previously offset the entirety of our consumption, but will not at current levels.
The heat pumps will just about pay for the cost difference between them and a new oil burner before their parts warranty is up. Add in the cooling, and the increased control and comfort we have, and it's a pretty sound investment, IMO.
As an anecdote, the conversation at the local bar in Rutland, VT the other night was all about people planning to get heat pumps, or promoting them after having them installed. Not wealthy tech enthusiasts, but bartenders, small business owners, and working class families. With the IRA inventives, and the price of heating oil -- it's becoming a normal thing, not an exception.
No you’re not exaggerating. I have both a high efficiency electric heat pump and a high efficiency natural gas furnace. Not only is the gas furnace significantly cheaper to operate, which surprised me given my heat pump is newer and among the most efficient available, but my gas furnace is also far more effective when the temperature is low (approaching freezing and below). The heat pump takes a lot longer to adjust temperatures and it feels like it struggles to keep up. The one complaint I have about my gas furnace is that it needs electricity to operate (ignition and blower fan) but that could theoretically be handled with a backup generator. There are alternatives that are fully independent of electricity though.
I’m also definitely wary of dependence on the grid and the sweeping rush to legislate every daily activity (cooking, driving, heating, etc) into that dependence. Over a decade back we had a bad storm that knocked out power for over 10 days. Luckily our natural gas and water service worked just fine, which kept us from freezing or starving. Ban based governance leaves a bad taste in my mouth.
Heat pump based electric heat in out mild climate emits less CO2, even factoring in transmission and conversion losses, than burning the gas in the most efficient condensing gas heater. It still costs about 3x as much in terms of energy cost, but emits less CO2.
However, the city regulators, like I said above, are stupid, so you often can't get a permit for a heat pump, because of noise ordinances. These things sound like an A/C compressor, so you can only install it if there is enough distance to your neighbors, and that's usually not possible in newer, denser developments, precisely the kinds where natural gas is banned, so you are now forced to use resitive heating, which uses 3-4x as much power as a heat pump, and costs more than 3x as much, due to our tiered electric prices (additional units cost more than early units)
when I looked into this for my house I found that gas was more like 10x cheaper than electricity. So a 3-4x efficiency advantage for a heat pump still made no economic sense
Sure, lets say $500 for a heat pump, $50 for a heater. Then what 'yield' are you getting on the $450. Let's say heat pump is 2x as efficient (should be understimate). Let's say that you run 2kw normal heater for 1 hr / day winter only for 3 months. That's 180kwh. @12c that's $21.6. So you save $10 a year. A 2.2% yield tax fee. So admittedly not great.
OTOH a mining rig, well who knows that IS complicated. You might lose money, or spend a lot of time tweaking but break even.
Heat pumps are dramatically more efficient. A good gas furnace is 95% efficient. Meanwhile, a ductless heat pump can be 300%. They more more energy than they consume. That's the huge advantage.
Converting gas heat to heat pumps, even if they have a gas heat backup for worst case days in northern latitudes, would still be a big win in the net environmentally.
While impressive to be boring electricity use was about 30GW but direct heating by gas and oil consumption was another 150GW or so. Heat pumps might reduce that in theory but still quite a way to go...
Of course, there's also the installation costs of a heat pump. But it did pay for itself in a reasonably short time. If it hadn't been that efficient it wouldn't have - first, there's the actual price, which is not as much these days as it used to be, but then there's the actual installation by a pro, and I believe that part has only gone up since then.
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