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Harnessing America's heat pump moment

heatpumped.org

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Re: Harnessing America's heat pump moment

#281

Post by ip26 »

kragen wrote: post #135
notyourwork wrote: post #119

Earlier quoted context omitted.

Some heat pumps are rated for much lower temps.

They can work at lower temperatures, but they do need the auxiliary heat to deice the outside coils.

the aux heat comes in because their output is a multiplier. At 30F, perhaps they produce 4x the heat as the electricity put in. At 0F, perhaps they produce 1.8x the heat. This means the output declines with temperature, until eventually they don't produce enough heat to hold temperature. Enter aux heat.

Cold weather heat pumps help because they stay above 1x for longer, but you also wind up needing to oversize a bit.

Re: Harnessing America's heat pump moment

#282

Post by thelastgallon »

caminante wrote: post #278
thelastgallon wrote: post #266

Earlier quoted context omitted.

I'm jealous of your financial learnings. However, your model is not accurate as it doesn't factor in the 4 degree improvement in comfort and indoor pollution from propane furnaces: Propane furnaces can cause indoor pollution through the release of pollutants like carbon monoxide (CO), nitrogen dioxide (\(NO_{2}\)), and benzene, which are byproducts of combustion. It also doesn't include the negative externalities bec…

I agree it's important to watch for these things. For externalities or immediate health benefits, heatpumps are pretty defensible. However, solar isn't a saint. Rare earth/mineral mining is hazardous plus only a fraction of solar panels are getting recycled properly. > this is doable in harsh Canadian winters with negligible solar and it breaks even It's doable alright. OP got subsidies (See comment re: risk free loa…

Yes, lets talk about subsidies. Fossil fuels have had and continue to have the most subsidies. Fossil Fuel Subsidies Surged to Record $7 Trillion/year: https://www.imf.org/en/Blogs/Articles/2023/08/24/fossil-fuel...

The wealth transfer you are alluding to, it is from the poor (everyone) to the rich (fossil fuel billionaires), isn't it?

Re: Harnessing America's heat pump moment

#283

Post by ip26 »

amarant wrote: post #75
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…

This is such a weird tale to hear. I heat my 2 story 147m2 house in Sweden with a single heat pump and it's downright cosy down to -10C. I have noticed that my office, which is located at the furthest possible place from the heatpump, tends to get a bit chilly when outdoors temperatures fall below -10°c. usually a blanket is enough to keep me toasty, but on the rare occasion that it gets real cold (below about -15°c)…

Some heat pumps bottom out at 35F, some at -15F. It seems to be down to the breed of heat pump, and there isn't much in between.

Re: Harnessing America's heat pump moment

#284

Post by ip26 »

bluGill wrote: post #50

When I replaced my furnace a couple years back I asked for a heat pump - a previous house had it and it worked great. Turns out my contractor didn't ask the right questions and so mine only works to 25F - it still outputs heat below that, but not enough to keep my house warm and so I use the backup furnace a lot more than I want to. A previous house the heat pump was sized to work to 14F. They make them that will wor…

gets to -30f where I live (about once every 10 years)

For this specific problem, I'm always inclined to just keep a 1800W space heater or two in the closet.

Re: Harnessing America's heat pump moment

#285

Post by nine_k »

kalleboo wrote: post #222
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…

For comparison, I just bought a house here in Japan. Installed 6 minisplit heat pumps across various rooms in the house. All together it cost me 750,000 yen ($5,000) for the hardware and 90,000 yen ($600) for the install.

How much time did it take?

Re: Harnessing America's heat pump moment

#286

Post by caminante »

thelastgallon wrote: post #282
caminante wrote: post #278

Earlier quoted context omitted.

I agree it's important to watch for these things. For externalities or immediate health benefits, heatpumps are pretty defensible. However, solar isn't a saint. Rare earth/mineral mining is hazardous plus only a fraction of solar panels are getting recycled properly. > this is doable in harsh Canadian winters with negligible solar and it breaks even It's doable alright. OP got subsidies (See comment re: risk free loa…

Yes, lets talk about subsidies. Fossil fuels have had and continue to have the most subsidies. Fossil Fuel Subsidies Surged to Record $7 Trillion/year: https://www.imf.org/en/Blogs/Articles/2023/08/24/fossil-fuel... The wealth transfer you are alluding to, it is from the poor (everyone) to the rich (fossil fuel billionaires), isn't it?

Please avoid unwarranted "whataboutism."

Re: Harnessing America's heat pump moment

#287

Post by db48x »

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…

Err, be careful. You made these improvements sequentially, not independently. Each one halved your costs and might still have done exactly that if done in the opposite order.

Re: Harnessing America's heat pump moment

#288

Post by adrianN »

Ekaros wrote: post #270
glxxyz wrote: post #256

Earlier quoted context omitted.

Yes the people selling solar systems all factor in aggressive future electricity increases, it's best to also see how it looks with more conservative rate increases. By my calculation in a reply above with the interest free solar loan it's an 8% return over 14.3 years.

Which to me is funny, when the electricity prices will clearly not rise when there is solar energy production from said panels. But might in other times.

Batteries for load shifting a few hours mitigate that quite a bit and are getting cheaper fast.

Re: Harnessing America's heat pump moment

#289

Post by tgma »

kortilla wrote: post #238
neltnerb wrote: post #234

I've got to throw out an obvious explanation. A third of the country rents. Renters pay the utility bills. Landlords pay for appliance upgrades. Why would the landlord put any effort into upgrading appliances when the cost of not upgrading them is borne by the renters? I've never rented at a place where they didn't want to fix broken equipment with the cheapest possible replacement. And no renter would ever consider…

Then why aren’t they in 2/3 of houses

Electricity is much more expensive than gas per J. You have to be ~3x more efficient to just break even.

Re: Harnessing America's heat pump moment

#290

Post by bell-cot »

db48x wrote: post #287
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…

Err, be careful. You made these improvements sequentially, not independently. Each one halved your costs and might still have done exactly that if done in the opposite order.

Look closer. How could his 20kW rooftop solar electricity have halved his initial monthly costs, when >3/4 of those costs were for propane heating fuel? (Vs. <1/4 for electricity.)
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