4 ms·

When I read the title, I wonder why air to water and air to ground heat pumps aren't more common in cold climates. Where it is 0°f on the surface, a few feet de

When I read the title, I wonder why air to water and air to ground heat pumps aren't more common in cold climates. Where it is 0°f on the surface, a few feet deep and you're back to 46°f. So we could have had efficiency 10 years ago instead of today?

pbourke 4y ago
Ground source heat pumps are 2-3x the cost of air source, and require a decent sized piece of land for installing the ground loop. Vertical installations use less surface area but are even more expensive since you’re drilling holes 400’ deep for the loop. Water source heat pumps are easier installations but require houses sited near a specific type of fresh water source that does not fully ice over in the winter or dry up in the summer.
- hinkley 4y ago
  Any studies in what these things do to the frostline? Heat pump is better than burning fossil fuels, but we also stop needing to treat system after system like it’s a bottomless well. We did that with real wells, then rivers, then the sky, then the ocean, then carbon dioxide and next up will be ground heat. There was a house last year that I think people were complaining about on Reddit, giant house out I’m the woods, all glass walls and heat pumps, labeled as green. It’s not a green building if you are 2x as efficient as fossil fuels but your house needs four times the BTUs of a reasonable design and 6 times a green one. Twice as efficient and half the heat loss is green. Blowing the surplus is not.
jltsiren 4y ago
Ground source heat pumps have become popular in the past 10-20 years. Natural gas has historically been cheap enough that replacing it may not be cost-effective if your house is connected to a gas grid. When replacing other heating sources, a ground source heat pump typically pays itself back in 5-10 years.
- zdragnar 4y ago
  Most homes with natural gas don't have enough space for a horizontal system, and vertical systems are very cost prohibitive. When you do have land, your horizontal space now is also being used up by a septic system. It's great if you can do it, but on the whole I suspect ground source is always going to be an expensive and difficult proposition for most people.
  - jltsiren 4y ago
    Based on a quick search, the typical costs for installing a vertical system to a single-family home are 15k to 25k euros in Finland. The contractors I found seem to discourage horizontal installations unless the bedrock is unusually deep. Drilling bedrock is cheap, while horizontal pipes have to be much longer, because the ground gets cold in the winter.
    - zdragnar 4y ago
      Odd, here drilling far eclipses excavation costs. Horizontal systems just need a backhoe to install, as you only need to dig below the frost line (we also get down to about -40 in winter). Vertical drilling requires more specialized equipment and so is more costly. Vertical systems are about $10k more expensive than higher end horizontal systems.

pbourke 4y ago

Ground source heat pumps are 2-3x the cost of air source, and require a decent sized piece of land for installing the ground loop. Vertical installations use less surface area but are even more expensive since you’re drilling holes 400’ deep for the loop. Water source heat pumps are easier installations but require houses sited near a specific type of fresh water source that does not fully ice over in the winter or dry up in the summer.

hinkley 4y ago
Any studies in what these things do to the frostline? Heat pump is better than burning fossil fuels, but we also stop needing to treat system after system like it’s a bottomless well. We did that with real wells, then rivers, then the sky, then the ocean, then carbon dioxide and next up will be ground heat. There was a house last year that I think people were complaining about on Reddit, giant house out I’m the woods, all glass walls and heat pumps, labeled as green. It’s not a green building if you are 2x as efficient as fossil fuels but your house needs four times the BTUs of a reasonable design and 6 times a green one. Twice as efficient and half the heat loss is green. Blowing the surplus is not.

jltsiren 4y ago

Ground source heat pumps have become popular in the past 10-20 years. Natural gas has historically been cheap enough that replacing it may not be cost-effective if your house is connected to a gas grid. When replacing other heating sources, a ground source heat pump typically pays itself back in 5-10 years.

zdragnar 4y ago
Most homes with natural gas don't have enough space for a horizontal system, and vertical systems are very cost prohibitive. When you do have land, your horizontal space now is also being used up by a septic system. It's great if you can do it, but on the whole I suspect ground source is always going to be an expensive and difficult proposition for most people.
- jltsiren 4y ago
  Based on a quick search, the typical costs for installing a vertical system to a single-family home are 15k to 25k euros in Finland. The contractors I found seem to discourage horizontal installations unless the bedrock is unusually deep. Drilling bedrock is cheap, while horizontal pipes have to be much longer, because the ground gets cold in the winter.
  - zdragnar 4y ago
    Odd, here drilling far eclipses excavation costs. Horizontal systems just need a backhoe to install, as you only need to dig below the frost line (we also get down to about -40 in winter). Vertical drilling requires more specialized equipment and so is more costly. Vertical systems are about $10k more expensive than higher end horizontal systems.