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Harnessing America's heat pump moment

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Re: Harnessing America's heat pump moment

#551

Post by danielsju6 »

reverendjames wrote: post #537
danielsju6 wrote: post #148

Maybe I have scar tissue from COVID prices but $20k to install a ductless heat pump vs. a $200 to throw a window A/C in or $700 for a portable heat pump. While I get that these heat pumps are better for the environment and much more efficient it's a last mile issue. The installers charge an arm and a leg and I'm not hurting enough to self install. I'm hoping the window heat pumps that just run off mains will be avail…

I live in Asia and I'm in charge of air conditioning at my company. A ductless A/c is approximately $1,200 installed. $20k? You should put a split unit in each room. If one breaks, go sleep in the other room. I have 6 of them installed in my apartment.

The $20k quote was for two ductless units, with two heads each, which would just cover the bedrooms in my home.

Quite the racket here in the US. They’re still a luxury product.

Re: Harnessing America's heat pump moment

#552

Post by danielsju6 »

stavros wrote: post #316
antonymoose wrote: post #315

Earlier quoted context omitted.

One question I would have is how distorted is your area, economically? I live in the Appalachian mountains, so one would think it should be reasonable labor rates for an area with a middle-low cost of living. Except that we have a lake the next town over which is entirely covered in millionaire lake houses, so anyone working a trade here can and will charge obscene rates to local, normal people because they can comma…

You've kind of exposed me, I'm not in the US, my question was in the first person but it was more that I'm curious as to the causes of what the commenters report. You may be right about the area just being HCoL, though.

Not in a HCoL area, quite the opposite in fact. Rural Maine.

Heat pumps are still a luxury product here that you only see on new homes or well financed gut remodels, which I think is the problem. As market is largely price insensitive individuals here, there’s no downward pressure.

Re: Harnessing America's heat pump moment

#553

Post by PaulDavisThe1st »

caminante wrote: post #525
PaulDavisThe1st wrote: post #478

Earlier quoted context omitted.

Could also just be the furnace. Incomplete combustion conditions can give rise to the symptoms mentioned here.

I doubt it's the furnace, unless there's a serial defect/recall. The problem is likely "between the keyboard and the chair." ;-)

I had a gas furnace that wasn't properly maintained as far as cleaning. Result: insufficient air flow for full combustion. Secondary result: CO build up in basement space. Tertiary result: asthma-like symptoms for me.

Re: Harnessing America's heat pump moment

#554

Post by PaulDavisThe1st »

dns_snek wrote: post #533
glxxyz wrote: post #443

Earlier quoted context omitted.

I’m not sure what you mean by ‘unsustainable’ nor ‘critical mass’ here. Of course not everyone can net meter- on a sunny but mild day with no-one using A/C nor heating and everyone contributing back to the grid it doesn’t work. My local utility is well aware of that, applications for permits to net meter have to be made, and only a fraction (something like 15%) of properties in each area can net meter. Also the gover…

Sorry, I should've been more specific, I can explain. > My local utility is well aware of that, applications for permits to net meter have to be made, and only a fraction (something like 15%) of properties in each area can net meter. Okay, that changes things. The way it worked here is that anyone in the country could install solar and get grandfathered into net metering (perpetually), and then at a certain point the…

> People would install 10-20kW worth of solar, overproduced massive amounts of energy in the summer and then in coldest part of winter (with heat pump COP dropping below 2), people expected to draw 4-10kW of power for heating and pay close to nothing all year round.

So this is more or less the exact same position that I'm in in northern New Mexico. We have 6.7kW of ground mount PV; we generate roughly 3x what we need in the summer, and roughly 1/3 of what we need in the winter (air source heat pumps for heat). Overall generation is close to 100% of our annual use.

In some ways I agree with the analysis but there are some mitigating factors. We live in an old adobe home that requires almost zero cooling during summer. For better or for worse, most new construction in the area is stick frame wood construction which even with reasonable insulation requires cooling during the summer. Guess who provides the power for that?

New Mexico is in a good position to combine solar PV with wind and be able to meet base load demand more or less continuously. It likely requires storage facilities that are on the order of 5-7 days of load, which would be enough to bridge most gaps in generation.

Our local utility actually provided two options for metering: one was what you're calling net metering, the other was credits for surplus on a monthly basis, with the credits generally being priced slightly below the purchase cost for the same energy. I would have been happy with either - the latter is perhaps fairer. However, they also stipulated that if you took credits, they could claim your PV as part of their own PV-adoption goals. So we took net metering instead.

Re: Harnessing America's heat pump moment

#555

Post by Reason077 »

Marsymars wrote: post #512
Reason077 wrote: post #509

Earlier quoted context omitted.

> ”Are you looking a at a heat pump heater? If so, how much of its energy would be pulling heat from the house that needs to be replaced by the home's heating supply anyway?” Heat pump water heaters pull heat from the outside . Usually with a split outdoor unit, just like normal A/C and heat pump systems. I’ve also seen models where the entire system (integrated storage cylinder for the heated water) is installed out…

Thanks, that obviously makes more sense. (I think I was thinking about heat pump clothes dryers at the same time I was making that comment.)

Heat pump dryers don’t cool the room either because they work in a closed loop. There’s no external vent removing hot air to the outside like a conventional dryer. So they pull heat from the room but also put it back in the room, and the overall effect is to warm up the room slightly.

Re: Harnessing America's heat pump moment

#556

Post by ssl-3 »

throw0101a wrote: post #544
ssl-3 wrote: post #499

Earlier quoted context omitted.

At face value, then in the worst case that's just 4 days per year of using resistive heat to keep a home warm. Which is, of course, very expensive to use -- but it's only expensive for those 4 days. Resistive heat can be avoided for the other 361.2425 days in a year. In the US (as of August of 2025), the average price of residential electricity per delivered kWh is $0.1762 [1]. If using resistive heat averages 4kW du…

> At face value, then in the worst case that's just 4 days per year of using resistive heat to keep a home warm. The design philosophy for using 1% is that you may end up having to run your heating (or cooling) 24/7 to keep up with temperature delta between outside and desired inside, but it will keep up with the demand. The rest of the time (99%) the mechanicals only run intermittently. Also note that the 1% would n…

I understood all of that when I wrote my comment.

The choir's appreciation towards this unnecessary lesson is not very good.

Re: Harnessing America's heat pump moment

#557

Post by caminante »

PaulDavisThe1st wrote: post #553
caminante wrote: post #525

Earlier quoted context omitted.

I doubt it's the furnace, unless there's a serial defect/recall. The problem is likely "between the keyboard and the chair." ;-)

I had a gas furnace that wasn't properly maintained as far as cleaning. Result: insufficient air flow for full combustion. Secondary result: CO build up in basement space. Tertiary result: asthma-like symptoms for me.

I believe it.

Re: Harnessing America's heat pump moment

#558

Post by Marsymars »

kragen wrote: post #531
Marsymars wrote: post #528

Earlier quoted context omitted.

A normal solar panel install wouldn't let me move to resistive heating regardless of size, my house simply isn't serviced with enough amperage. My gas furnace is 100k BTU give-or-take, so I'd need >100 amps for heating alone.

Yes, 100kBTU/hour, which I assume is what you mean, is 29kW, which would be 133 amps at 220 volts, or 610 amps at 48 volts. But solar only supplies power intermittently; you'd need to draw much more power than that when the sun was shining to blast your mansion with 29 scorching kilowatts around the clock. Maybe 100kW, about 2000 amps at 48 volts. For that you'd need ten parallel #0 wires (8.3-mm-diameter copper bars…

Er, yeah, the math there looks right, but my point is that with a non-exotic solar setup, I can't supply more amperage to my house via solar than what my grid connection allows... though actually looking at how the ratings work, solar capacity is going to be limited by the busbar rather than the grid connection... so I could upgrade my panel to 200A, keep 100A service and get maybe 80A of solar capacity at the max if I got around the solar sizing limits... which, as we've both noted, isn't enough to heat my house resistively.

While your description was funny, my house isn't especially palatial - it's a pretty bog-standard <2000 sqft house from the 70's with new windows and attic insulation. Unfortunately, the insulation can't otherwise be upgraded much without extension/expensive renovations, and it just takes a lot of energy to keep it heated when it's -35° outside.

Re: Harnessing America's heat pump moment

#559

Post by kragen »

Marsymars wrote: post #558
kragen wrote: post #531

Earlier quoted context omitted.

Yes, 100kBTU/hour, which I assume is what you mean, is 29kW, which would be 133 amps at 220 volts, or 610 amps at 48 volts. But solar only supplies power intermittently; you'd need to draw much more power than that when the sun was shining to blast your mansion with 29 scorching kilowatts around the clock. Maybe 100kW, about 2000 amps at 48 volts. For that you'd need ten parallel #0 wires (8.3-mm-diameter copper bars…

Er, yeah, the math there looks right, but my point is that with a non-exotic solar setup, I can't supply more amperage to my house via solar than what my grid connection allows... though actually looking at how the ratings work, solar capacity is going to be limited by the busbar rather than the grid connection... so I could upgrade my panel to 200A, keep 100A service and get maybe 80A of solar capacity at the max if…

Yeah, I agree. I have the advantage of living in a subtropical climate, which seems like less of an advantage when the dengue season hits, but the 3400W heat pump my wife and I bought last year does a fine job of heating our 18m² bedroom—and, far more importantly, cooling it when it's +35° outside. You, by contrast, have apparently bought a palace somewhere closer to Antarctica.

200m² of solar PV can only provide about 45kW peak anyway, and on the roof under two meters of snow it would provide roughly zero. One of the advantages of vertical panels like Joey Hess's system discussed here the other day is that they don't necessarily get snowed on, and in some orientations they produce the most energy in the winter. But without enough insulation there's a limit to what you can do. This was apparently a major reason for hanging tapestries in castles older than yours.

Every solar setup ten years from now is going to look exotic by our current standards. Think about automobiles before and after the Model T, or shipping before and after the steam locomotive.

If I was contemplating heating a mansion on Hoth with 2000 amps of low-voltage DC from solar panels, I don't think I would want it connected to a single busbar. I think I'd want it in 5–40 separate circuits to limit the risks from possible short circuits.

Re: Harnessing America's heat pump moment

#560

Post by prlambert »

switchbak wrote: post #89
prlambert wrote: post #54

Earlier quoted context omitted.

Yes this is actually the worst – when open minded people get a heat pump for "the right reasons" and then have buyer's remorse. Completely backfires the transition. Do you have a ducted or ductless heat pump? Sounds like ducted, and if so that might be part of it too. The air cools down in the ductwork and if that's not accounted for - i.e. you reuse ductwork that was meant for a furnace – you run into issues like th…

Hi Paul - I'm a big fan of Quilt from Vancouver Island. It seems to me that you're helping to close the loop on some of the quality concerns that the parent commenter has. Inappropriate sizing/installation and poor product selection seem like common issues from HVAC installers that aren't particularly well versed on heat pumps. Wishing you continued success, and that hopefully it'll be available in Canada at some poi…

Also sorry I missed this, not only are we in Canada, we just signed our first partner on Vancouver Island – in Victoria, Pacific Heat Pumps: https://www.pacificheatpumps.ca/

We'll have a partner in Nanaimo very soon as well.

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