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Re:New York to Ban Natural Gas, Including Stoves, in New Bui... by jillesvangurp on Saturday April 29, 2023 @02:59PM (#35755952)
Heat pumps are about 250-300% efficient. Relative to resistive heating which is of course 100% efficient. Gas is about close to 100% (you loose some via exhaust). Ground source heat pumps work pretty much anywhere. Air source heat pumps can be more challenging but can also work at more extreme temperatures. They don't stop working but their efficiency drops a bit. And of course resistive heating doesn't stop working.

Heat pumps are used all over Scandinavia and well into the arctic circle, including rural areas in the parts of Scandinavia (i.e. the polar circle) that see extreme temperatures far more regularly and for far longer periods than NY. Of course relative to NY, they do have a more reliable power grid and excellent building standards. Triple (not double) glazing is the norm there, for example.

And of course more rural places would also feature wood stoves as a backup. There is mostly no gas network there; especially not in rural areas. Before heat pumps became popular about thirty years ago they would have used that or oil based systems.

Re:New York to Ban Natural Gas, Including Stoves, in New Bui... by nucleardog on Saturday April 29, 2023 @03:15PM (#35756132)
> And of course resistive heating doesn't stop working.

Well except…

> Of course relative to NY, they do have a more reliable power grid

Okay, yeah. That would pretty much be my concern.

Having been without power for over two weeks in the past 12 months the propane tanks and propane stove / furnace / water heater have been a lifesaver.

Powering the control boards / fans with a generator (or even UPS in a pinch) is a lot simpler proposition than trying to generate enough power to heat my house, water, and food with resistive heating.

Re:New York to Ban Natural Gas, Including Stoves, in New Bui... by UncleMeat on Saturday April 29, 2023 @05:34PM (#35757444)
Gas furnaces don't work without power by default. The fan that pushes the hot air through your house won't work. Many gas furnaces have electrically powered safety features that won't allow the furnace to function if the power is out.
Re:New York to Ban Natural Gas, Including Stoves, in New Bui... by nucleardog on Monday May 01, 2023 @10:07PM (#35782367)
Covered that already:

> Powering the control boards / fans with a generator (or even UPS in a pinch) is a lot simpler proposition than trying to generate enough power to heat my house, water, and food with resistive heating.

My furnace runs on 120V power pulling ~8A when running. That's ~1kW. Comparable sized resistive heating would use about 9kW.

1kW for a few hours a day is easy to provide through a cheap generator, a couple small solar panels and a single marine battery, or apparently a ~$220 wind turbine I can order on Amazon that can output up to 1200W. 9kW is a whole different ball game.

And that's just heating. My stove uses in the order of single-digit watts for seconds at a time. It can also just be lit with a match without power. My water heater does run a small exhaust fan while it's heating, but again... we're talking hundreds of watts instead of kilowatts.

Yes, all these options pretty much still need power, but the smaller power requirements are a hell of a lot easier to provide than the power needed for resistive electric heating. I could run my water heater off of a desktop UPS.

Re:New York to Ban Natural Gas, Including Stoves, in New Bui... by SV_BubbleTime on Saturday April 29, 2023 @03:38PM (#35756349)
> Heat pumps are about 250-300% efficient.

Sure. When we’re talking about the temperature band they work in. Once it hits 0C the efficiency is very low, and by -10C is almost doing nothing at all. At that point you have two things happening…

1. You are using electricity to warm your coils outside to keep frost and snow off them.

2. You are using drastically inefficient heat for your home.

200-300% in their band under ideal conditions, maybe. Seems like cherry picking.

Re:New York to Ban Natural Gas, Including Stoves, in New Bui... by wtallis on Saturday April 29, 2023 @04:14PM (#35756709)
200-300% efficient is what a bad heat pump would do under ideal conditions. Good heat pumps have a coefficient of performance above 3 for temperatures above freezing (and above 4 for only mildly chilly outdoor temperatures), and still well above 2 at temperatures around 15˚F/-10˚C.
Re:New York to Ban Natural Gas, Including Stoves, in New Bui... by SV_BubbleTime on Saturday April 29, 2023 @05:00PM (#35757140)
Cool. But, how much of the US gets below 17F? I think it’s a lot.
Re:New York to Ban Natural Gas, Including Stoves, in New Bui... by wtallis on Saturday April 29, 2023 @05:03PM (#35757166)
17˚F isn't the point at which my heat pump stops working. It's just the lower temperature conventionally used as a point of comparison on the spec sheets for such devices. There's another column on the spec sheet for 47˚F (where my heat pump model is listed as having a CoP of 3.6).

And as for the question about colder climates: it's not a matter of whether an area can occasionally experience temperatures below eg. 17˚F. What matters is whether you'll ever experience daily highs that are cold enough to prevent heating the house.

Re:New York to Ban Natural Gas, Including Stoves, in New Bui... by 8note on Saturday April 29, 2023 @05:08PM (#35757208)
The question is what the cop is at -20C though, which is a fairly common winter temperature, and you really need heat at -40
Re:New York to Ban Natural Gas, Including Stoves, in New Bui... by wtallis on Saturday April 29, 2023 @05:13PM (#35757255)
I was responding specifically to this bit: "Once it hits 0C the efficiency is very low, and by -10C is almost doing nothing at all." I've refuted that. If you want to discuss some more distant goalposts, I won't be able to offer firsthand evidence.
Re:New York to Ban Natural Gas, Including Stoves, in New Bui... by SV_BubbleTime on Tuesday May 02, 2023 @01:21AM (#35783670)
You are free to refute that.

Doesn’t make it wrong.

At -10C you are hardly pulling anything from the air, but you are spending electricity to keep your coils free of frost, as inefficiently as possible.

Do you not know how a heat pump works in cold weather?

Re:New York to Ban Natural Gas, Including Stoves, in New Bui... by abigail95 on Saturday April 29, 2023 @04:18PM (#35756748)
What heat pump model are you using for your numbers so I can confirm its specs?
Re:New York to Ban Natural Gas, Including Stoves, in New Bui... by 8note on Saturday April 29, 2023 @05:11PM (#35757237)
For pretty standard specs, you should be able to look at any old heat pump
Re:New York to Ban Natural Gas, Including Stoves, in New Bui... by jillesvangurp on Saturday April 29, 2023 @04:19PM (#35756755)
I'm not cherry picking, I'm merely describing the status quo in a place of the world that can be pretty extreme compared to NY.

You are talking about air source heat pumps. There are actually variants of that technology that work fine at -20 and below. -20 is actually quite far above absolute zero. The challenge is not that there isn't enough energy but finding and pumping liquids around that can absorb that "heat" and actually stay liquid. Efficiency indeed drops below zero. But it still works.

However, ground source heat pumps are not dependent on the air temperature at all and work anywhere you can get a decent temperature gradient from the ground. Which is pretty much anywhere except maybe on top of the arctic ice sheet in e.g. Antarctica.. Stick a few pipes in the ground and get them deep enough and you can have an nice cozy house pretty much anywhere that is not located on a few miles of ice. NY is perfect for that. No permafrost there and stable temperatures below ground throughout the year.

And again, they have been doing this for decades in places like Finland, Sweden, Norway, Greenland, etc. That's because this stuff works and is reliable and efficient enough. This is not some new kind of science fiction technology. Millions of households depend on this when it gets to minus 40C and below (about the same in C and F). And having lived in Sweden and Finland, I can tell you that they like their houses heated properly there and it really gets that cold up north. They don't use gas in houses there at all and never have. There are no gas distribution networks there. Oil based heating has been phased out in most places there a long time ago. But people forget that that stuff has to be trucked in and trucking anything in gets tricky when there's a few meters of snow on the roads. Heatpumps, resistive heating, district heating, and wood based stoves is pretty much all they use there. District heating is not common outside the more populated areas (i.e. most of the Arctic region) with the exception of the larger towns and villages.

Re:New York to Ban Natural Gas, Including Stoves, in New Bui... by magicalhippo on Saturday April 29, 2023 @05:10PM (#35757234)
This guy[1] ran a test on his home during last winter, and found that his mini split had a COP of around 1.5-2.5 down to -10C.

The data wasn't terribly correlated to temperature, though he didn't have a mini-shed for the outside unit to protect it from snow, so it probably had to defrost more often during the less-cold, snowy days.

FWIW here in Oslo, we've been using a mini split as the main heat in our home, where it's often -15C for long stretches during winter, and can get down to -25C. It's in the main livingroom, and we do supplement the upstairs bedroom with resistive foil floor heating during the coldest periods. Other than that it's doing great, and comparing the electricity bills with friends and colleagues who don't have a heat pump it's definitely helping a lot.

[1]: https://youtu.be/fxEqVuiHhM0?t=523

Re:New York to Ban Natural Gas, Including Stoves, in New Bui... by nonethewiser on Saturday April 29, 2023 @05:26PM (#35757362)
> And of course more rural places would also feature wood stoves as a backup.

Sure, but that’s worse than natural gas

Re:New York to Ban Natural Gas, Including Stoves, in New Bui... by achates on Sunday April 30, 2023 @09:24AM (#35762309)
Now multiply that by the efficiency of a gas power plant.

I'm so glad I swapped out my heat pump for gas heat. My power bill went down and the house is much more comfortable.