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Heat Pumps – The Well-Tempered Future of A/Cs

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221–230 of 406 posts

Re: Heat Pumps – The Well-Tempered Future of A/Cs

#221
post #81

Earlier quoted context omitted.

It's not just buzz. It's more efficient than resistive heating and modern units have better performance in cold temps. Hence the push to promote them. The downside is that you have added complexity driving up installation costs and reliability down.

Walk around in the American Heating and Refrigeration conference for a while to get a feel of these trends, this was specifically called out by many manufacturers as driven by the green movement.

[deleted]

Re: Heat Pumps – The Well-Tempered Future of A/Cs

#222
post #128
post #48

Earlier quoted context omitted.

Although natural gas is "clean" compared to, say, coal, the advantage of a heat pump is that it uses less total energy than natural gas. That means it would be more efficient to run a heat pump off a natural gas power plant than to burn natural gas to heat your home directly.

People's AC summertime electric bills regularly get into triple-digits - it's not uncommon to hear someone with a moderately sized home having a $200-400 electric bill in the summertime. However, even in the midst of winter, gas heating bills rarely climb above $100 monthly. What am I missing here? It seems a heatpump, while more efficient, will cost significantly more to operate. Natural Gas is cheap ... and clean e…

I'm fairly certain we're near - or even past - the point where burning natural gas to run a generator to power a heat pump will use less gas than burning the gas directly for heat.

Re: Heat Pumps – The Well-Tempered Future of A/Cs

#223

When I needed a new air conditioner a couple years ago I was quoted $17,000 for a heat pump. I can only guess at that point whatever energy cost savings it would bring would never be realized within the service life of the system. I went with a $6000 standard replacement AC unit.

What kind of a system were you installing? We had a heat pump installed three years ago for less than $5k Canadian. Can't remember if we got a rebate on top of that or not.

I can only speculate, but in my last replacement scenario, higher-SEER units (17+) had dramatically higher quotes, to the point where it was difficult to justify financially. On top of that, there were dramatic (~100%) variations in prices on similar equipment (but different brands) between installers. I can only imagine that regional differences are yet another source of variation...

All that is to say, my first guess is that the GP was quoted a high-SEER unit for name-ish brand equipment.

Re: Heat Pumps – The Well-Tempered Future of A/Cs

#224

When I needed a new air conditioner a couple years ago I was quoted $17,000 for a heat pump. I can only guess at that point whatever energy cost savings it would bring would never be realized within the service life of the system. I went with a $6000 standard replacement AC unit.

That must have included furnace replacement components for cold weather (e.g electric heat strips). Otherwise, heat pumps are essentially the same as modern A/C units.

Almost certainly. Proper/modern heat pumps do not need heat strips until -20F or so

Re: Heat Pumps – The Well-Tempered Future of A/Cs

#225

Earlier quoted context omitted.

Are you sure you aren't getting quotes for a ground-sourced (AKA geo) heat pump? We just installed a 4.5 ton (overkill for your sqft) 20 seer unit for $18000.

That seems crazy high too though, I just got a 5 ton for a 2300 sq ft house with 12kw heat strips including duct work for 10k. The duct work was $3800.

I agree that seems expensive, but I wouldn't be totally shocked if a high-SEER, "name brand" unit with a pricey contractor could get that high. I had >100% cost variation for similar equipment between HVAC contractor quotes the last time I replaced a unit.

Re: Heat Pumps – The Well-Tempered Future of A/Cs

#226
post #183

Earlier quoted context omitted.

Well, the no-gas thing upsets me because cooking on modern electric cooktops/stoves is still staggeringly awful.

Induction cooktops heat faster and more evenly than gas

There's many good reasons induction cooktops aren't used in commercial kitchens... and those reasons apply for home-cooks as well.

Re: Heat Pumps – The Well-Tempered Future of A/Cs

#227
Wow, I never cease to be amazed at how few of the HN comments have anything to do with the original post.

I guess I'll jump on the bandwagon, while my comment is tangential, it does have to do with the article's focus on reducing greenhouse gases and fuel consumption.

Switching to a heat pump should be done in all cases where a traditional A/C is being replaced, but the biggest bang for the buck is in how the house is constructed in the first place. "Passive solar" orientation and insulation can prevent a HUGE amount of energy consumption. To point to another HN post article:

https://thebaffler.com/salvos/construction-time-again-sisson

I've been saying for 20 years here in San Diego county, that if developers built track housing with passive solar orientation, and covered them with photovoltaic, the neighborhoods would be power plants. They could offer free HOAs and free electricity for the life of the house. Instead, we orient, organize and build for the maximum efficiency of a group of people who are only onsite for about 1 year (the developers) and then leave the people who live there for decades holding the bag.

Re: Heat Pumps – The Well-Tempered Future of A/Cs

#228

Earlier quoted context omitted.

Sure, but it can happen anywhere. I was just reading yesterday about a person who died in Portland of heat during the dome. Same with cold weather, if the gas/electric goes out during the winter. There's really only a few places one can live with moderate enough weather to avoid those scenarios.

>>Same with cold weather, I 100% disagree with this... Heat is made by everything, waste heat is a byproduct of all modern things, and there are TONS of easy low cost ways to make heat even it is just as simple as burning something. Also the body makes head naturally so adding layers to trap this heat does not require continual inputs from an outside resource Cooling on the other hand is MUCH harder, and electricity…

> Cooling on the other hand is MUCH harder, and electricity is really the only avenue to make cooling.

Gas-powered fridges and coolers have existed for about two hundred years and are still a normal technology today - often used for camping and off-grid life.

Here's a whole bunch of propane fridges for your viewing pleasure: https://bensdiscountsupply.com/collections/propane-refrigera...

Re: Heat Pumps – The Well-Tempered Future of A/Cs

#229
post #135
post #131

Earlier quoted context omitted.

It's actually difficult to say what the cost would be if everyone switched over. The reason is that natural gas is subsidized, both on the production side (at least in the US, which wants energy security) and on the consumption side (because it's politically unpopular to let people freeze to death). Of course, electricity prices are also affected by subsidies. Figuring out the true operating prices would require some…

It seems to me, there is no future where a heatpump can be the only source of in-home heating then. 1) Natural Gas is vastly cheaper in most/all of the US. 2) Homes still require an alternative heating source when temperatures drop to low levels (coincidentally when people need heating the most). So, even if a heatpump is technically more efficient in terms of emissions, the technology does not solve all of the probl…

2-4x seems like a stretch, and would only apply in areas with very high electric rates. My last house was heated with a builder-grade heat pump (HSPF around 8), and my winter electric bills were around $150-200/mo. My current house has natural gas heat, and similar level of appliances/EVs/lighting, and winter bills electric bills are around $100/mo. This is the same town and the electric rate didn’t change, so the net cost of heating my old house with a heat pump was only $50-$100/mo. Meanwhile my winter gas bill in this house, subtracting baseline summer usage, runs more than that.

The only backup heat I had with the heat pump was electric resistance heat, which I needed to use only once or twice each winter for a few hours at a time.

Re: Heat Pumps – The Well-Tempered Future of A/Cs

#230

When I needed a new air conditioner a couple years ago I was quoted $17,000 for a heat pump. I can only guess at that point whatever energy cost savings it would bring would never be realized within the service life of the system. I went with a $6000 standard replacement AC unit.

What kind of a system were you installing? We had a heat pump installed three years ago for less than $5k Canadian. Can't remember if we got a rebate on top of that or not.

Had mitsubishi units installed in the northeast USA a couple of years ago, for a 1.5k sqft house all of our quotes were ~15K.
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