Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Harnessing America's heat pump moment

heatpumped.org

Post reply on HN
Print view View original

191–200 of 571 posts

Re: Harnessing America's heat pump moment

#191

Post by theluketaylor »

glxxyz wrote: post #187
estimator7292 wrote: post #67

Earlier quoted context omitted.

You're talking about geothermal heat pumps which are far less common than air-to-air heat pumps because they are far more expensive. These are entirely disjoint concepts.

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.

Re: Harnessing America's heat pump moment

#192

Post by Animats »

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 price is around $400. They're not very standardized. You get IR images of a house, which is good for finding leaks but not quantitative enough to size a heating and cooling plant.

This would be a great drone application. Fly over and around the house. Build a 3D model of the house and paint heat loss on top of it. Crunch on data to get the engineering info needed to correctly size HVAC. Also discover big heat leak points. Turn this from experienced guessing into measurement.

Then submit that data sheet to multiple sites that offer heat pumps.

Startup opportunity here.

[1] https://www.energy.gov/energysaver/thermographic-inspections

Re: Harnessing America's heat pump moment

#193

Post by eldaisfish »

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.

auxiliary heat is a separate heat source for the indoors.

Most cold climate heat pumps run a defrost cycle to melt ice off the outdoor unit. that's different from auxiliary heat.

Re: Harnessing America's heat pump moment

#194

Post by psunavy03 »

ssuds wrote: post #129
darth_avocado wrote: post #107

Earlier quoted context omitted.

> most homeowners in california actually see operating cost parity or a slight decrease, even with super expensive electricity But you’re missing my first point though, installing a heat pump system comes with a price tag of tens of thousands of dollars. I’m not doing that if my operating cost is at parity or a slight decrease. It’s the same reason people are no longer incentivized to install solar. And to add to tha…

The first point is very valid too. There was an energy commission study a few years ago, and up front cost is pretty consistently one of the biggest barriers to heat pump adoption. I think there's some nuance to that, though. Even replacing a furnace + AC in California amounts to tens of thousands of dollars! It's not that heat pumps are expensive, it's that construction work in general is expensive. When you frame i…

. . . and how many people do you assume own $3M homes? Good grief.

Re: Harnessing America's heat pump moment

#195

Post by eldaisfish »

orev wrote: post #142
mithr wrote: post #26

Electricity costs are a big factor in this, imo. Rates for my northeast town increased by ~25% in 2024 and are going up by another ~10% this year. It's a hard sell to spend a large amount of up-front money (even after rebates, which decreased this year) to convert to a system that will cost you more than you pay today, and may not work as well in cold weather (every heat pump company I talked to suggested keeping my…

Heat pumps are just air conditioners in reverse. They use the same amount of electricity whether heating or cooling. While many people have air conditioners, and grids seem to be able to handle them in the summer, an assertion that the grid can’t handle them in the winter is doubtful. Plus there are fewer people using them in the winter (just because fewer are installed). Most people in the NE heat with oil, gas, or…

> They use the same amount of electricity whether heating or cooling

This is completely wrong. The amount of power depends on the temperature delta. When cooling, you are typically not cooling your home to 30 degrees Celsius below the outdoor temperature. However, when heating, you are typically heating your home to around 20 degrees above outdoor temperature. Heating consumes more power than cooling.

Re: Harnessing America's heat pump moment

#196

Post by goalieca »

orev wrote: post #142
mithr wrote: post #26

Electricity costs are a big factor in this, imo. Rates for my northeast town increased by ~25% in 2024 and are going up by another ~10% this year. It's a hard sell to spend a large amount of up-front money (even after rebates, which decreased this year) to convert to a system that will cost you more than you pay today, and may not work as well in cold weather (every heat pump company I talked to suggested keeping my…

Heat pumps are just air conditioners in reverse. They use the same amount of electricity whether heating or cooling. While many people have air conditioners, and grids seem to be able to handle them in the summer, an assertion that the grid can’t handle them in the winter is doubtful. Plus there are fewer people using them in the winter (just because fewer are installed). Most people in the NE heat with oil, gas, or…

I would be curious to know the difference. In summer you might find 30c outside and inside 20c so a difference of 10c. In winter it can reach -30c and inside is 20c. This is 5x more!

Re: Harnessing America's heat pump moment

#197

Post by doubleg72 »

morshu9001 wrote: post #127
darth_avocado wrote: post #107

Earlier quoted context omitted.

> most homeowners in california actually see operating cost parity or a slight decrease, even with super expensive electricity But you’re missing my first point though, installing a heat pump system comes with a price tag of tens of thousands of dollars. I’m not doing that if my operating cost is at parity or a slight decrease. It’s the same reason people are no longer incentivized to install solar. And to add to tha…

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

I just got 10 new 585w panels and inverter for under $5k. A battery is gonna cost me $1500 but at $350 month for electricity, not sure how you can claim it not worth it.

Re: Harnessing America's heat pump moment

#198

Post by eldaisfish »

etimberg wrote: post #138
crgwbr wrote: post #106

Earlier quoted context omitted.

That’s true, but still doesn’t always make heat pumps the most cost effective choice to operate. For example, last winter I paid an average of $0.24/kWh for electricity vs $0.05/kWh for natural gas. Even if a heat pump had a perfect 4.0 COP all winter, gas would be ~15% cheaper. Electricity prices really need to come down before it will be viable for everyone.

Not to mention, lots of places have time of use electricity pricing which makes it even worse. This is the problem with running my heatpump when its cold, some of the coldest times (right before dawn) coincide with peak time-of-use prices

where do you live that the highest electricity prices are before dawn?

Re: Harnessing America's heat pump moment

#199

Post by eldaisfish »

starkparker wrote: post #99
amarant wrote: post #75

Earlier quoted context omitted.

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)…

It's the insulation. While it depends on the location and geography, I'd wager that American homes are probably less well insulated than Swedish homes because they didn't have to be. That contrasts quite a bit with Swedish home standards, which have long been built more air-tight and with considerably better insulated even if they're of comparable age. This has been true for decades, became even more stark in the 198…

it isn't insulation.

It depends primarily on your electricity and methane prices. In Ontario, Canada, electricity is cheap enough that heat pumps are cheaper than methane on all but the very coldest days, even if your home insulation is older than 1980 standards.

Post reply on HN