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Harnessing America's heat pump moment

heatpumped.org

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Re: Harnessing America's heat pump moment

#211

Post by Aspos »

Animats wrote: post #192

Everybody seems to agree that installation costs way too much. There's a few parts to this. Everything has to be carefully sized - power, pipe sizes, unit locations. You need to put a house's thermal profile (how much heat loss, how much air leak, how much thermal mass) along with the regional thermal profile into an engineering calculation which computes what you need. Thermographic inspections are a thing.[1] Usual…

I would argue that accurate sizing is not that important as labor constitutes the bulk of the cost. My total bill was about $20K and going for 30% less capacity would net about $19K so its easier just to go for the maximum. Calling in an IR imaging drone would certainly cost more than the potential savings from accurate sizing.

Unlike gas furnaces which basically can only do ON or OFF, heat pumps can regulate the heat with much higher granularity.

What certainly calls for innovation is managing the labor costs. In my case installation involved way too many people and way too many visits.

Re: Harnessing America's heat pump moment

#212

Post by chongli »

danielsju6 wrote: post #207
chongli wrote: post #169

Earlier quoted context omitted.

This is talking about cold-climate heat pumps. A $200 window AC isn't going to heat your house when it's way below freezing outside. $20k USD is insane though. I live in Ontario and we paid $12k CAD (pre-government subsidy) for a modern heat pump with a backup high efficiency furnace for when temperatures dip down to -40 or lower.

True. We have natural gas and an existing steam radiator setup though, for the two months a year window heat pumps can't keep up. The upfront investment alone would heat my house for 10-20 years. Honestly, just piling more insulation in the attic and doing an energy audit will probably put the ROI out another 10+ years... I'm hoping the newer window units that are being rolled out to the NYC market will be good enoug…

There’s another alternative: a mini-split. Larger than a window unit, with a refrigerant lines you run yourself but with the actual refrigerant pre-charged inside the unit, so you don’t need to handle it yourself (which usually requires a license).

Mini-splits tend to be much cheaper than full installations.

Re: Harnessing America's heat pump moment

#213

Post by next_xibalba »

kevin_thibedeau wrote: post #170
morshu9001 wrote: post #127

Earlier quoted context omitted.

I feel like home solar makes no sense without subsidies, even now with economies of scale. Commercial solar may be a different story.

If you DIY everything and go with server rack batteries you can keep the costs low enough for a reasonable break even point. Any middleman is going to gouge.

That is awesome and I wish I had these skills. But it also rules out the vast majority of homeowners.

Re: Harnessing America's heat pump moment

#214

Post by Merad »

smnrchrds wrote: post #183
Merad wrote: post #111

Earlier quoted context omitted.

I have to agree. I've spent about 2/3s my life in houses with heat pumps and the last 5 years with a gas furnace (the rest being wood heat as a child). Mostly in Western NC and Eastern TN near the mountains, so chilly but not extreme cold. Heat pumps work, but they aren't nearly as _pleasant_. You can write essays about the efficiency of heat pumps, how lukewarm air works just fine to warm the house, how heat pumps a…

I have never had a heat pump, so I wasn't aware of this shortcoming. Could you please explain a bit more how different it is with heat pump compared to furnace?

The heat pump will always produce air that is warmer than the temp in the house, but as the temp outside drops the temp of the air coming out of the vents also drops. So on a very cold day when the house temp is say 70F, the system might only be putting out air that's 75-80F. The air coming out of the vents doesn't really _feel_ warm and it may take an hour or two to raise the temperature in the house when you wake up or get home in the evening.

In my experience at least with relatively modern heat pumps (roughly 2000 and newer) it doesn't matter that much when outside temps are above freezing. But it quickly starts to become noticeable as temps drop into the 20s.

Re: Harnessing America's heat pump moment

#215

Post by danielsju6 »

glxxyz wrote: post #177
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…

It's the opposite for me, much bigger ROI on the heatpump than solar. Rural property, 10 years old, ~3,500 sq ft + basement, in Canada where summer can be above 30C (86F) and winter below -30C (-20F). Electricity costs (Canadian) 7.6 ¢/kWh off-peak and 15.8 ¢/kWh on-peak here. I spent C$40K (about US$30k) on a ground source aka 'geothermal' heat pump to replace furnace powered by propane tank. I kept propane for on-d…

For me it helped with the ROI because I couldn't go any larger than a 6kw array due to roof shape/exposure. Only roof mounted solar is permitted in my community :/ So a ductless saved us energy in the summer months vs. window units, so I could bank more with net metering when the sun was shining.

Re: Harnessing America's heat pump moment

#216

Post by JeremyPOsborne »

prlambert wrote: post #54
blahedo wrote: post #33

People are reluctant to install them because they don't work as well as the good old boilers we'd be replacing. I'm not saying they can't, and I'm not saying that there are zero models out there that work. But in practice, a lot of us that have interacted with heat pumps have the specific experience that they get anemic as the temperature goes down and eventually become unable to do much of anything. I live in the mi…

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…

We account for duct losses at Electric Air when sizing. It’s baked into industry standard Manual J sizing calculators and other methods. ManJ isn’t perfect find for this purpose.

In this case, contractor should have advised the heat pump would not keep up and recommended a different solution.

Re: Harnessing America's heat pump moment

#217

Post by EngCanMan »

mastax wrote: post #201
Animats wrote: post #192

Everybody seems to agree that installation costs way too much. There's a few parts to this. Everything has to be carefully sized - power, pipe sizes, unit locations. You need to put a house's thermal profile (how much heat loss, how much air leak, how much thermal mass) along with the regional thermal profile into an engineering calculation which computes what you need. Thermographic inspections are a thing.[1] Usual…

Isn’t it important to right-size non-heat-pump installs anyway? Too large a system causes short cycling, humidity problems, temperature swings. I have read installers habitually guesstimate over size to over charge (rather than do the proper calculations).

The reality is that this is all solving a problem that people don’t have.

Forced air is a terrible way to heat a building yet thats how most homes are heated, and it is good enough for most people.

If you perfectly size a furnace for the coldest days of the year, it is now oversized for the other 90% of days.

The cheapest way is to install a multi stage heating/cooling system that works on first stage most of the time, and second when it needs to, like having 2 small furnaces. This passes the ‘good enough’ test for the vast majority of homeowners.

Re: Harnessing America's heat pump moment

#218

Post by glxxyz »

theluketaylor wrote: post #191
glxxyz wrote: post #187

Earlier quoted context omitted.

The prices when I looked weren't that different- it was about C$30k Canadian for air source and C$40k for ground source (which I went with).

30K would be on the higher end for air source. My install this year was 25k CDN including a lot of duct work. 40K is also on the low end for geothermal. I'm guessing you were able to trench instead of drill? If you can afford ground source it's by far the best option in cold climates. Steady ground heat means you get the same efficiency all year round. The install can be eye-watering though.

Yes horizontal loop, 200 metre trench ~2m deep with 6 pipes at the bottom. Took 3 days for a 20 ton excavator to dig and fill in the trench. Maybe I got lucky with the installer but it wasn't eyewatering. Vertical loops do cost a lot more. Repairing the lawn with turf or professional landscaping would have cost more than the install, so I did it myself with a tractor, some spare topsoil, and a few bags of Costco grass seed.

Re: Harnessing America's heat pump moment

#219

Post by glxxyz »

mattmaroon wrote: post #210
glxxyz wrote: post #177

Earlier quoted context omitted.

It's the opposite for me, much bigger ROI on the heatpump than solar. Rural property, 10 years old, ~3,500 sq ft + basement, in Canada where summer can be above 30C (86F) and winter below -30C (-20F). Electricity costs (Canadian) 7.6 ¢/kWh off-peak and 15.8 ¢/kWh on-peak here. I spent C$40K (about US$30k) on a ground source aka 'geothermal' heat pump to replace furnace powered by propane tank. I kept propane for on-d…

Solar in northernly climates is still not practical. (I’m Canada adjacent.)

People told me that, but I did the calculations myself and the impact on my energy bills is real. Net metering is essential though, so not everyone can do it.

Compared to say SoCal I generate 2/3 as much per year, much less evenly- a lot more in summer than winter, whereas further south there's less variation year round. Cooler temperatures improve solar panel efficiency too. There are online solar potential calculators if you want to compare for yourself.

Re: Harnessing America's heat pump moment

#220

Post by EngCanMan »

yojo wrote: post #162
sitharus wrote: post #146

Earlier quoted context omitted.

I was shocked when I saw the price of heat pump installation in the US, even with an existing ducted system. There’s no reason a reversible heat pump system should be significantly more expensive than a cooling only one.

It’s bonkers. I bought a pre-charged ductless mini split to DIY. Took my dad and I about four hours to do the install. So call it 8 hours of semi-skilled labor. The unit was $1350, I added a line set cover, pad and feet for another $200, and needed about $200 in electrical equipment - it was a long wire run and code requires installing a disconnect box. The only special tool was a hole saw bit for running the coolant…

Umm, I encourage you to do that math a little closer. A contractor would have to;

Come to your house to quote, and only land 1/4 quotes maybe.

Schedule the workers

Order the equipment.

Get an electrical permit.

Pay for the truck and all the tools.

Insurance for the company and trucks.

Advertising costs

Warranty and callbacks

I can assure you that this is not the get rich quick scheme you may think it is.

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