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I mean a ton of heat pumps are being installed. New houses tend to have heat pumps. The problem is with old houses who already have a heating system installed,

by rapsey 2y ago

I mean a ton of heat pumps are being installed. New houses tend to have heat pumps. The problem is with old houses who already have a heating system installed, it is crazy to overhaul to a heat pump as the cost is not even close to being sensible.

darkr 2y ago
This. The cost of installing and upgrading a big old drafty Victorian house to a COP 4+ efficiency where the running costs actually beat oil/gas would have a break even point way past the end of my lifetime.
- valenterry 2y ago
  Nope, it's very simple. Just don't try to heat up water to heat the house. Use an aircon. In fact, their efficiency is even better. 4+ is already standard, 5+ is good and there are even models that go beyond 6. Only problem can be if you have a lot of tiny rooms - in that case it's expensive to install everything.
  - darkr 2y ago
    Those figures are for the unit itself. It takes a lot less energy to heat air than it does to heat water, but water retains heat for much longer. What matters is the SCOP for the system as a whole. In a traditional Victorian house with a fireplace in every room, radiant heat will provide far greater efficiency than a forced air system, in which all of that warm air will literally go straight up the chimney.
    - valenterry 2y ago
      > Those figures are for the unit itself. No. > What matters is the SCOP for the system as a whole. That's exactly what my numbers are. They are the efficiencies for moving the heat-energy from the outside air into the inside air, assuming constant 20 degrees celcius indoor temperature and a specifically weighted outdoor temperature (there are multiple types of SCOPs, depending on the climate-zone and I was refering to the moderate one as it is present in most of middle Europe). Whether you transfer the heat from the outside air (or some other medium) into the indoor air or into the indoor water does not matter - except that for the latter, you will need to consider that the water has to still transfer the heat to the indoor air, so you need to know how hot the water will have to be to calculate the SCOP correctly for your house. > In a traditional Victorian house with a fireplace in every room, radiant heat will provide far greater efficiency than a forced air system, in which all of that warm air will literally go straight up the chimney. What kind of "efficiency" are you even talking about? Can you please provide a definition and some example calculation? Otherwise it's meaningless to discuss.
deleted 2y ago
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antupis 2y ago
It depends on where, like here in Finland those houses that do not have regular or ground thermal heat pumps start to be weird ones.
gryzzly 2y ago
exactly, our neighbour has a oil heating system which is a size of a room in her cellar. simply uninstalling and removing it is beyond anything she, a pensioner, can pay. unless the government picks up the replacement costs, she will keep burning oil.
tfourb 2y ago
Basically no one ever has recommended throwing out a well-working existing heating system. But heating systems, including radiators, tanks and furnaces, have limited life spans. Usually 20-30 years. At some point it is not economical to repair them, spare parts may not even be available anymore or laws have changed that require particularly old and dirty furnaces to be removed. In those cases, heat pumps are usually the more economical choice, depending on government incentives and other considerations. For example, it is quite certain that current EU-legislation concerning the inclusion of domestic fossil fuel usage in the CO2-certificate trading scheme will result result in price increases of 20-40% for natural gas and heating oil by 2035 or so. This includes older houses. Modern heat pumps are quite capable of heating even less insulated houses economically.

by rapsey 2y ago

darkr 2y ago

This. The cost of installing and upgrading a big old drafty Victorian house to a COP 4+ efficiency where the running costs actually beat oil/gas would have a break even point way past the end of my lifetime.

valenterry 2y ago
Nope, it's very simple. Just don't try to heat up water to heat the house. Use an aircon. In fact, their efficiency is even better. 4+ is already standard, 5+ is good and there are even models that go beyond 6. Only problem can be if you have a lot of tiny rooms - in that case it's expensive to install everything.
- darkr 2y ago
  Those figures are for the unit itself. It takes a lot less energy to heat air than it does to heat water, but water retains heat for much longer. What matters is the SCOP for the system as a whole. In a traditional Victorian house with a fireplace in every room, radiant heat will provide far greater efficiency than a forced air system, in which all of that warm air will literally go straight up the chimney.
  - valenterry 2y ago
    > Those figures are for the unit itself. No. > What matters is the SCOP for the system as a whole. That's exactly what my numbers are. They are the efficiencies for moving the heat-energy from the outside air into the inside air, assuming constant 20 degrees celcius indoor temperature and a specifically weighted outdoor temperature (there are multiple types of SCOPs, depending on the climate-zone and I was refering to the moderate one as it is present in most of middle Europe). Whether you transfer the heat from the outside air (or some other medium) into the indoor air or into the indoor water does not matter - except that for the latter, you will need to consider that the water has to still transfer the heat to the indoor air, so you need to know how hot the water will have to be to calculate the SCOP correctly for your house. > In a traditional Victorian house with a fireplace in every room, radiant heat will provide far greater efficiency than a forced air system, in which all of that warm air will literally go straight up the chimney. What kind of "efficiency" are you even talking about? Can you please provide a definition and some example calculation? Otherwise it's meaningless to discuss.

deleted 2y ago

[deleted]

antupis 2y ago

It depends on where, like here in Finland those houses that do not have regular or ground thermal heat pumps start to be weird ones.

gryzzly 2y ago

exactly, our neighbour has a oil heating system which is a size of a room in her cellar. simply uninstalling and removing it is beyond anything she, a pensioner, can pay. unless the government picks up the replacement costs, she will keep burning oil.

tfourb 2y ago

Basically no one ever has recommended throwing out a well-working existing heating system. But heating systems, including radiators, tanks and furnaces, have limited life spans. Usually 20-30 years. At some point it is not economical to repair them, spare parts may not even be available anymore or laws have changed that require particularly old and dirty furnaces to be removed. In those cases, heat pumps are usually the more economical choice, depending on government incentives and other considerations. For example, it is quite certain that current EU-legislation concerning the inclusion of domestic fossil fuel usage in the CO2-certificate trading scheme will result result in price increases of 20-40% for natural gas and heating oil by 2035 or so. This includes older houses. Modern heat pumps are quite capable of heating even less insulated houses economically.