4 ms·

You can still use a heat pump that takes the heat from the exhaust air to warm the fresh air. That way you can get the same amount of heat as if you were using

You can still use a heat pump that takes the heat from the exhaust air to warm the fresh air. That way you can get the same amount of heat as if you were using three+ times as many graphics cards. I usually use GPUs for heating during winter as the power has to be used anyway, so why not get ethereum for it.

delecti 4y ago
> You can still use a heat pump that takes the heat from the exhaust air to warm the fresh air Unless I'm misunderstanding part of this proposed setup, I'm pretty sure this doesn't work. The higher efficiency of heat pumps comes from the fact that the outdoors is an effectively infinite (for the purposes of a house) source of temperature differential. You can only move as much heat as exists, so you can't use a heat pump to multiply a finite heat source.
- NorwegianDude 4y ago
  I'm not sure what there is to misunderstand. Heat is taken for the outgoing hot air, and transferred to the fresh air coming in. So instead of hot air going out, the air going out will usually be freezing.
  - mook 4y ago
    That sounds like heat recovery ventilation; while useful, it serves a different purpose than heat pumps (which heats up enclosed spaces without the ventilation). Also HRVs normally work with whatever existing air and don't use extra heated air…
    - NorwegianDude 4y ago
      You are recovering the heat from the ventilation, yes. But you're doing so using a heat pump. Check out e.g. Nibe F750 with SAM40. I'm using the heat pump to heat water using the extracted air. That water is then used for floor heating, ventilation air heating and ofc. hot water.
  - delecti 4y ago
    In my experience, people usually try to avoid exchanging air with the outdoors when they're concerned about significantly heating/cooling their homes. If you're exchanging air then a heat pump could super heat/cool the outgoing air, and that's the piece I was missing from your proposal.
    - NorwegianDude 4y ago
      A house must exchange air. Better insulated houses are basically air tight, so you must have ventilation to get fresh air. A pro with that solution is that the extracted air has a high temperature all year, making it more efficient that using a heat pump to extract heat from outside that might be -30 celcius. A downside is that the amount of air is limited, so if you need more heat then you have to supplement it with something else. You get it, but it seems there are a few others that don't realize that a heat pump can also be used to increase efficiency by reducing the heat lost. While I do get that it's unknown to most people, some people here perfectly illustrates the Dunning-Kruger effect...
stouset 4y ago
> You can still use a heat pump that takes the heat from the exhaust air to warm the fresh air. I don't think you understand how heat pumps work. Heat pumps have significantly greater than 100% "efficiency". They don't turn electricity into heat. They use electricity to move preexisting heat, and it turns out that's far more efficient in terms of Joules of heat delivered to your home per Joule of energy spent. In fact, for any given Joule of energy spent, you can generally move two to three Joules from outside your home to inside of your home. If the source of heat you're pumping is coming from resistive heating you're using electricity for, you're only getting 1 Joule of heat for every Joule of electricity. Adding heat pumps to this system doesn't help you. > I usually use GPUs for heating during winter as the power has to be used anyway, so why not get ethereum for it. Because owning and operating a heat pump is almost certainly cheaper than the costs of owning and operating a mining rig, even offset by the value of the cryptocurrency you generate. You'd almost certainly be better off by heating your home with a heat pump and using the energy savings to buy that same cryptocurrency. The exceptions to this are if you are in a location where energy is extremely cheap, or perhaps if you generate more than your household usage of electricity (including resistive heating) through solar or wind but aren't able to sell that electricity back to the grid.
- NorwegianDude 4y ago
  I know very well how heat pumps work, and I find it ironic that you assumes others don't know because you don't understand it or haven't heard of it. A heat pump doesn't have to take heat from the outside. By using heat from the extracted air, you can use whatever you want to generate heat inside and get multiple times the effective heating as it's reused. Use wood, electrical floor heating or GPUs. It doesn't matter. The energy from the extracted air is transferred to the fresh supply air. The exhaust air will be freezing. Also, electricity has been expensive the last two years, but mining has still been profitable, considering I already have some GPUs in my workstation and home server. You don't earn money by using a heat pump, you do(or at least did) by mining. By mining and using a heat pump on that energy I increase the usage of that energy. Win win win.
  - stouset 4y ago

delecti 4y ago

> You can still use a heat pump that takes the heat from the exhaust air to warm the fresh air Unless I'm misunderstanding part of this proposed setup, I'm pretty sure this doesn't work. The higher efficiency of heat pumps comes from the fact that the outdoors is an effectively infinite (for the purposes of a house) source of temperature differential. You can only move as much heat as exists, so you can't use a heat pump to multiply a finite heat source.

NorwegianDude 4y ago
I'm not sure what there is to misunderstand. Heat is taken for the outgoing hot air, and transferred to the fresh air coming in. So instead of hot air going out, the air going out will usually be freezing.
- mook 4y ago
  That sounds like heat recovery ventilation; while useful, it serves a different purpose than heat pumps (which heats up enclosed spaces without the ventilation). Also HRVs normally work with whatever existing air and don't use extra heated air…
  - NorwegianDude 4y ago
    You are recovering the heat from the ventilation, yes. But you're doing so using a heat pump. Check out e.g. Nibe F750 with SAM40. I'm using the heat pump to heat water using the extracted air. That water is then used for floor heating, ventilation air heating and ofc. hot water.
- delecti 4y ago
  In my experience, people usually try to avoid exchanging air with the outdoors when they're concerned about significantly heating/cooling their homes. If you're exchanging air then a heat pump could super heat/cool the outgoing air, and that's the piece I was missing from your proposal.
  - NorwegianDude 4y ago
    A house must exchange air. Better insulated houses are basically air tight, so you must have ventilation to get fresh air. A pro with that solution is that the extracted air has a high temperature all year, making it more efficient that using a heat pump to extract heat from outside that might be -30 celcius. A downside is that the amount of air is limited, so if you need more heat then you have to supplement it with something else. You get it, but it seems there are a few others that don't realize that a heat pump can also be used to increase efficiency by reducing the heat lost. While I do get that it's unknown to most people, some people here perfectly illustrates the Dunning-Kruger effect...

stouset 4y ago

> You can still use a heat pump that takes the heat from the exhaust air to warm the fresh air. I don't think you understand how heat pumps work. Heat pumps have significantly greater than 100% "efficiency". They don't turn electricity into heat. They use electricity to move preexisting heat, and it turns out that's far more efficient in terms of Joules of heat delivered to your home per Joule of energy spent. In fact, for any given Joule of energy spent, you can generally move two to three Joules from outside your home to inside of your home. If the source of heat you're pumping is coming from resistive heating you're using electricity for, you're only getting 1 Joule of heat for every Joule of electricity. Adding heat pumps to this system doesn't help you. > I usually use GPUs for heating during winter as the power has to be used anyway, so why not get ethereum for it. Because owning and operating a heat pump is almost certainly cheaper than the costs of owning and operating a mining rig, even offset by the value of the cryptocurrency you generate. You'd almost certainly be better off by heating your home with a heat pump and using the energy savings to buy that same cryptocurrency. The exceptions to this are if you are in a location where energy is extremely cheap, or perhaps if you generate more than your household usage of electricity (including resistive heating) through solar or wind but aren't able to sell that electricity back to the grid.

NorwegianDude 4y ago
I know very well how heat pumps work, and I find it ironic that you assumes others don't know because you don't understand it or haven't heard of it. A heat pump doesn't have to take heat from the outside. By using heat from the extracted air, you can use whatever you want to generate heat inside and get multiple times the effective heating as it's reused. Use wood, electrical floor heating or GPUs. It doesn't matter. The energy from the extracted air is transferred to the fresh supply air. The exhaust air will be freezing. Also, electricity has been expensive the last two years, but mining has still been profitable, considering I already have some GPUs in my workstation and home server. You don't earn money by using a heat pump, you do(or at least did) by mining. By mining and using a heat pump on that energy I increase the usage of that energy. Win win win.
- stouset 4y ago