this post was submitted on 24 Sep 2023
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The article doesn't say just how much more expensive heat pumps are when comparing to gas furnaces. I live in one of the states at the top of that picture and just replaced my 20+ year old furnace and AC compressor. I specifically asked about heat pumps and they were reluctant to even price it out for me. It was over twice the cost. In addition they said the area I live in would almost certainly require an aux heat source, which they recommended gas for because direct electric heat is so horribly inefficient. I ended up going with the 98.5% efficient gas furnace, which also came with incentives and rebates from the power company.
Direct electric heat is very efficient. Practically 100%.
My understanding is that you would only need the aux source during extreme cold. So very rarely.
Right - in fact, from my knowledge, heat pumps only see use over direct electrical heating because they are effectively more than 100% efficient. They move more heat energy from outside to inside than they use in the transmission.
The breakdown between gas and electric heating isn’t necessarily a matter of how efficiently the energy is used once it gets to the home, it’s how expensive it is to get it there in the first place. In a lot, if not a majority, of places, it’s much cheaper to get gas piped in than it would be to pay for the same amount of heating via direct electric resistance. Heat pumps change the equation because they can make electric heating in places that don’t get outrageously cold economically competitive with gas.
Yep PGE makes it so that gas is tremendously less expensive than electrical in California. So a lot of people who would normally be upgrading right now will not be doing so.
My heat pump is around 300% efficient. It adds 3X the energy into the house than it spends by stealing that energy from outside.
Except when it's very cold outside, which is what was discussed here. Heat pumps are great (have one in my home), but it might not be ideal in very cold areas, especially if electricity prices are high compared to other energy sources.
You need to be in a very, VERY cold area for that to matter. While these places exists, I'm sure it's not the case for a lot of the states I've seen marked in that article. Heat pump can heat the inside of your house even when it's freezing outside.
...and it will never go below 100% because most have resistive heating as backup.
That's a misleading number. In most other cases where we are using electricity--motors, CPUs, lighting, etc--we consider the heat generated to be inefficiency. It might be more accurate to say that electric resistance heating is 100% inefficient.
If you're using resistance heating to heat your home, using electricity that's originally produced by natural gas, then you're using more natural gas compared to burning that gas for heat directly in a home furnace. Now, electric resistance heating can be a choice when it's fed by clean electrical sources otherwise. Even then, though, you would prefer a heat pump if possible.
And a heat pump powered by a natural gas power plant will bring more heat into the house for the same amount of gas, including losses in transmission. It will likely be more expensive to install and run, though.
But the heat is the goal.
What do you consider "extreme" cold?
I don't know. It's a curve though, not a cutoff.
Icing conditions can also be a factor; freezing rain in the high 20's F (~-4C for those who can't F) will build up a layer of ice on the outside unit especially since it's already the coldest thing around. That ice prevents air from circulating through, so it loses effectiveness. Running the strips for about a half hour or so, then running the air conditioner for about a half hour will defrost it quite effectively and restore it to efficient operation. It is my understanding some systems even do this automatically.
https://www.youtube.com/watch?v=MFEHFsO-XSI
I'd explain, but he does it better.
For anyone thinking about watching this video, it's GREAT, and has a ton of other interesting tech videos on the channel.
Knew what video was the second i saw the youtube link :D
And what is the problem with a gas hybrid heat pump? It's an ideal solution for places that get very cold, use the gas furnace for the weeks when it's below -5 and use the heat pump for many months around that. It's one of the most efficient ways to use a heat pump as you don't have to bully it through the coldest part of winter with very bad COPs, you're only using it when it's most efficient. And when your heating period is very long, that will only benefit your seasonal COP. So of course it's more expensive than a simple furnace, but it will also save loads of energy and redeem itself after 5-10 years.
The best part about this is you already have an AC, aka a heat pump, but you don't use it for heating?
I live in New England and gas hybrid is what I looked at. I’m sure it would be very effective, while greatly reducing various air pollution. They quoted $22k to replace my existing furnace and ac, and this was before the big round of price gouging. That is a lot of money.
I live in southern Wisconsin, and that's about what they quoted me in the past year for a top of the line system of both the AC and furnace. That's a multi-stage system that runs at a low level all the time (that's the most efficient way to run it). This is before tax incentives.
A more basic system was around half that cost. If your AC and furnace need replacing, anyway, it's not much more.
Tbf, minimum cost is going to be $4k, so for him/her the minimum was $8k. We don’t know their financial situation but that is a lot of money to cough up.
Thing is, it's not much more than replacing the AC/furnace, anyway. They only last around 20 years. Often less, because people don't do preventative maintenance on them.
Totally agree, but not everyone has the finances to do a big upfront cost like that. Same story as the $10 vs $50 pair of shoes from a century ago.
First off, that's what government incentives are for. Exactly the sort of program that OP is pointing towards.
Second, this stuff breaks eventually. That's part of home ownership. I realize this isn't a perfect solution, but you really do need to plan for this sort of thing. In the case of my wife and I, we were easily able to cover it with a home equity loan (along with solar panels and a new rood and a few other things). We could only do that because we've been in the same house for over a decade, live in an area with rising house prices, and have good credit. These things will easily pay for themselves in the long run, so the home equity loan makes good sense.
But I'm fully aware not everyone can do that. This is a place where government needs to step in to do it faster.
The article does eventually mention that heat pumps cost more, plus replacement rate is limited by when existing stuff goes bad., after way too much filler text.
Of course they gloss over it a bit and use an example “ if a heat pump cost $5,000 …”. If I could do that, I would have. I did get one quote before giving up, and even if you read it as “$5,000 more than conventional options…”, it’s not close to that either.
However the biggest problem with the article is claiming that being more efficient means less operating costs and make a claim about how much money you’ll save. Sure, they’re very efficient , but it’s more complicated than that. Where I live, the preferred alternative is natural gas, and it’s price per energy is much cheaper than electricity, so you’d save very little, if any
I was renting a place while rehabbing my home. We completely removed the natural gas from our house and went induction range, electric oven, heat pump water heater and heat pump air conditioner/furnace. The place we were renting was about 3 blocks away. It had an old but not terribly old gas furnace, standard gas range and oven, gas water heater, and no air conditioner. It turned out to be a really great way to compare the two setups. One mostly gas, somewhat inefficient (which is standard out there), the other ultra modern power saving equipment throughout the house. The rented place had baseboard heating as well, but that is so wildly inefficient that we turned them off and never used them. Sweet jesus it was like lighting cash on fire.
My last bill gas + electric at the old place was $210. My first full month bill at the new place was $90, and that includes an AC running at the new place that didn't exist at the old place.
It is a shocking level of savings, and we aren't even in winter yet where my gas bills at the inefficient place would regularly hit $200.
The first 4 HVAC companies I called told me the same thing. They said I had to have a back up natural gas or resistance based electric heater. They don't know what they are talking about. My current heat pump can operate down to -30 C. The coldest it ever gets here is -16 C and that's only for a few hours per year.
I think "they don't know what they are talking about" is a bit much; it's possible they're required by code. They're usually labeled "emergency heat" on the thermostat because that's their intended use.
I've been watching the Texans comprehensively fail to deal with weather that's slightly different than what they're used to, and just shaking my head the whole time, thinking to myself "you guys don't have backup heaters? No space heaters? None of you own generators? Not a single one of you has a hearth and fireplace? I guess you can't shoot "it's unusually chilly" so you're out of ideas, huh?"
I've got five different ways to heat my home from four energy sources, because sometimes things aren't perfectly ordinary. I'm from the Sandhills of North Carolina, it rarely dips below freezing here, I've NEVER seen it below 20F, we usually get 2 or 3 inches of snow a year in 3 or 4 flurries. When I was in 7th grade, we got three feet of snow. Between a kerosene heater to get us through the ensuing power failure and then heat strips to defrost the outside unit once power came back on, we were safe and comfortable.
Backups aren't for "most of the time."