this post was submitted on 23 Feb 2024
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The power company here keeps pushing heat pumps, but it frequently gets down below freezing and often below 0F during the winter, and my understanding is that heat pumps just can't efficiently keep up with that, if at all, so supplementary heat is still needed. Is that no longer the case? "Every American" includes a lot of people in that same situation.
The article cites that it would save the average American $550 a year on utilities, so when you consider that it costs ~$15-30k to have a heat pump installed, we're looking at a 27-55 year break-even point.
It makes sense for new construction but they seem to be advocating for retrofitting existing homes, and I just don't see how they're making the claim that it's economically viable. It'd take some mega subsidies to make that possible for most people, I think.
COP is the ratio of moved heat to electricity used. Modern air-to-air heat pumps can maintain a COP of 2.5 or more below 5 def F. The 2.5 COP is important because it's the efficiency cutoff where, above that, even using methane (natural gas) to generate electricity, send that electricity to the home, and use that electricity to power a heat pump, you will use less methane than you would if you burned it directly for heat in your home.
A COP greater than 1 will still be better than resistive heat, and many modern heat pumps can maintain a COP above 1 well below 0 deg F.
Now, wherever you live, methane could be subsidized for homeowners, so the direct costs to the homeowner don't pencil out directly at the 2.5 COP cutoff, but that's no longer a question about efficiency, but around local government not correctly pricing methane.
EDIT: there was a week in January where it stayed below -10 deg F where I live, and my heat pump kept my apartment at 70 deg F with no issues, and only needed to run 27% of the time.
In addition to Thejevans points, your cost estimate is very high. That cost would be in line for a geothermal heat pump, which is far more efficient. Air to air heat pumps can be installed for more like $3-10k in most residential homes. And on the higher end that is a big house that is probably saving more than $550 a year.
Can you show me where you're getting those figures? I was basing my estimate on a quick google search of prices, and the estimate provided for air-source heat pumps here. (MassSave is an organization that promotes energy efficient and climate friendly appliance solutions in Massachusetts), which seems to suggest $22,000 is an average cost, which is in line with the other estimates I was finding. ($10-$20k to buy the unit and $15-$30k including installation.)
Edit: To be clear, I'm not trying to be contrary or argumentative; I've been looking into heat pumps as a possible option for us for years and if they've become justifiable from a cost perspective, I'd love to get those details.
I looked up prices in Massachusetts, they are higher than the national average. Looks like 2 main factors:
1 A higher than usual percentage of mini splits vs central air. These will be more efficient and have a lot of comfort benefits, but are considerably pricier then retrofitting a central air system. So if you are retro fitting CA, you could come in under average.
2 MAs impressive $10k+ incentive system for whole home heat pump systems has resulted in HVAC companies raising prices, because of course it has. This is why we can't have nice things.
I just looked up the energy star list of high efficiency heat pumps, chose the largest model, and googled a few of the prices to get about 7 to 10k. Which is still absurdly high for what they are, but I was looking at the highest efficiency ones so I guess they have fancier compressors or something else that lets them raise the price. I also got an average cost to replace an AC unit of 500 to 2500 dollars.
At the end of the day a air source heat pump is just an air conditioner with a 10 dollar reverseing valve, though they typically use very efficient air conditioners and add an emergency space heater aswell. Well if your being predantic an air conditioner is a heat pump, but generally in climate threads heat pump is shorthand for one that works in reverse for heating as well as cooling.
I really can’t imagine the level of grift you would need to have to get from that to 22k, unless you were using ground source or retrofitting central heating into a building that previously lacked it, though in that case you would probably use several minisplits to replace individual radiators or baseboard heaters.
I had a new multistage NG furnace, a heat pump, and a garage heater installed for 24000$, with a 6k rebate coming my way. Where did you get your numbers?
I did this about a month ago.
Answered this below, but it was based on a quick google search and the estimate provided by an organization in my state that's promoting heat pumps and other energy efficient appliance solutions. Based on what other folks are saying, it sounds like their estimate is just grossly high.
We hit 0 degrees a month ago and the heat pump was not running. Only the furnace would run when it was that cold. I've read that they can work down to 0 though, so I think the installer might have configured it wrong. I've been meaning to call them to get that looked into.
From what I read there are ones that work in the negatives mostly around -10 as the limit though.