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Comment by seunosewa | Hacker News Reader

"One of the most common complaints about heat pumps, experts said, was that they would stop providing heat on very cold days. But advances to heat pump compressors have made them more efficient, cost effective and successful at providing heat in colder temperatures."

Yeah this is a key issue that shouldn't be glossed over like this. We need more data about how much they have improved.

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My heat pump has what they call "Emergency Heat" which is basically just some heating coils they add in like a traditional electric furnace. So on days when the heat pump can't do it's thing, it works just like the old furnace that I replaced. Emergency heat also kicks on when the differential between the current temp and desired temp is large. 99% of the time, the heat pump seems to do just fine on it's own.

Newer heat pumps still have electric heat, but also can extract heat from ambient air down to -10F. Mr Cool for the DIYer, Mitsubishi for the workhorse. Reverser valves do the work of switching heat pumping direction.

I suspect that most of the reluctance comes from people using gas furnaces, not people using electrical resistance heating. Compared to electrical resistance heating, a heat pump has no downsides other than a higher initial cost which is very quickly paid back from energy savings, since electrical resistance heating is staggeringly expensive.

Resistive heat is staggeringly expensive to operate in cold climates and the people most often using it are renters who have no choice. The heat pump law and subsidy I'd most like to see is for retrofitting rental units with heat pumps, especially in places where the renter is paying for utilities. Make sure the landlord can't block the improvement (or force them to do it and cover some costs).

I like carbon pricing in theory as a market solution, but it really only works when the person paying the extra cost can make different choices about their usage. Those of us rich, old, or lucky enough to own homes can retrofit for efficiency as we see fit. Renters are stuck with whatever heat source, air sealing, and insulation they draw in the lottery, especially in the current housing crunch. If the renter is also paying the utilities the person with the carbon-pricing incentive to make improvements isn't allowed to and the landlord has no reason to change.

Where is an electric furnace typical? Electric heat would be several times more expensive for me to operate than my gas furnace.

>One of the most common complaints about heat pumps, experts said, was that they would stop providing heat on very cold days.

Heat pumps have "emergency" electrical resistance heaters for this. Source: owned homes with heat pumps for the past 20 years.

My parent tried heat pumps twice. They are incapable of even handling the usually not-very-severe winters of central Texas without resorting to turning on their pathetically weak resistance heaters, an those can cost nearly $100/day to run! Their second Gen system was much newer and more expensive, but not much better.

The definitely are not capable of handling any subfreezing temperatures. Natural gas is, overall, FAR more efficient for heating when the supposed efficiency of the heat pump gets slammed by the inefficiency of electric heat.

So that answers the OP's question of why we don't use them: They're fiddly, expensive to buy, and both don't work in, and are insanely expensive to operate in the cold.

That's not been my experience and I live north of 46 degrees latitude, with an average December temperatures much lower than, for example, Abilene, TX, with a total electric bill in the neighborhood of ~$250/month in December/January. The Coefficient of Performance for electrical resistance heat, and natural gas are both 1.0, (so you need the same number of joules to heat the air to the same temperature from either energy source). Maybe electric rates are really high in Texas in the winter? Or the gas rates are really low, and the house is huge?

Is it possible your parent's house is not well insulated/sealed? Potentially _really_ uninsulated? I've talked to people here (45 degrees latitude) who are happily using their heat pumps and we're looking at models for ourselves. One caveat being the people I'm talking to live in above average performance homes (in terms of insulation and air sealing).

For a video that glosses over the details but loudly proclaims this “ugly truth” there’s this one. I can’t tell if he is a paid shill for the gas industry or just obtuse, or maybe a voice of common sense in the wilderness….

https://youtu.be/GhAKMAcmJFg

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