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Right now 50% of the power I can buy at any given time is generated by burning natural gas - this is true in 80% of the country. So it doesn't really matter -

by Aloha 3y ago

Right now 50% of the power I can buy at any given time is generated by burning natural gas - this is true in 80% of the country. So it doesn't really matter - it might if we build some nuclear or whatever, but right now, it doesn't.

toomuchtodo 3y ago
Right, you're not paying the true cost of that energy [1] [2]. I'm saying, what happens when you have to. That changes market signals, perhaps drastically, assuming the per ton cost of CO2 emitted (which is optimistically ~$50/ton but likely closer to $200/ton, assuming the only two ways to handle emitted carbon are to either not emit it or direct air capture and sequester underground ie Climeworks and company). When consumers must pay for the externalities of their fossil fuel consumption, it's no longer economically competitive. If you can't pass carbon taxes, have to outlaw new gas service like many jurisdictions are attempting to do. High level, looking at the cost of natural gas alone is insufficient for these discussions; you have to look at the entire supply chain and externalities to arrive at a true "apples to apples" comparison. (matters now, but won't as the blended cost of renewables and storage [firm generation] declines below the floor fossil gas needs to sell at to keep the infra running, and that infra already leaks like a sieve [3]) [1] https://energypost.eu/new-u-s-study-damage-per-ton-of-co2-costs-185-not-the-official-51/ https://energypost.eu/new-u-s-study-damage-per-ton-of-co2-co... [2] https://www.nature.com/articles/s41586-022-05224-9 https://www.nature.com/articles/s41586-022-05224-9 [3] https://www.edf.org/climate/methanemaps https://www.edf.org/climate/methanemaps
- amluto 3y ago
  In a sensible world, i.e. not California IOU-land, you are of course correct. In California, for IOU customers, electric rates are pushing $600/MWh. You can figure out how exactly you want to apply the emission factors: https://www.epa.gov/energy/greenhouse-gases-equivalencies-calculator-calculations-and-references https://www.epa.gov/energy/greenhouse-gases-equivalencies-ca... But you will have a hard time making the math come out in favor of electricity. Unless you have a really nice heat pump, your electricity is 100% carbon-free, and you rule out gas-fired heat pumps [0] or cogen [1], you’re probably better off burning natural gas and using the money you save to offset your carbon usage in some more effective manner than throwing it at your local utility so they can burn it. Fundamentally, carbon pricing can work when CO2 emissions are expensive and the clean alternatives are reasonably priced. California has a major problem with the latter requirement. [0] They exist but seem very rare. [1] Reputable companies make these, but the devices are large and are not friendly for residential installations.
  - Aloha 3y ago
    In a parallel comment I ran the numbers - and you're absolutely correct here.
- Aloha 3y ago
  Even if you price CO2 emissions in, both electricity and natgas rise - because of how much electricity is generated by gas - and how inefficient thermal generation is. 1 metric ton of carbon is about 19 Mcf of gas burned. 19 Mcf of gas contains about 1.65MW of electric power (assuming combined efficiency of generation and transmission of 30% - if you can provide a framework for better electricity efficiency I'm open to it). It'd add about $121 to the price per MW or 35 cents per 10,000 BTU It'd add about $10 to the price per Mcf of gas or about 10 cents per 10,000 BTU Assuming that 50% of your power has a carbon surcharge on it, we can halve those numbers - 17.5 cents per 10,000 BTU. So once I plug those into my HP Calculator - that raises assumed electricity prices to 90 cents per 10,000 BTU and gas prices to 24 cents per 10,000 BTU. The heat pump still ends up being more expensive over the entire operating range - note that HP efficiency goes down with temperature. So at 40f it costs 35 cents on my 5T HP to generate 10,000 BTU of heat, at 10f 65 cents per 10,000 BTU of heat. Gas however is steady at 29 cents per 10,000 BTU of heat - no matter the operating temp.
  - itsoktocry 3y ago
    Thank you. The "but fossil fuel externalities!" crew can't seem to comprehend just how efficient, cheap and abundant fossil fuels are, and that we can't simply shut them off or double their price tomorrow without massive economic consequences.
    - Aloha 3y ago
      Bear in mind, I'm pro alternative energy, I'm a major advocate for nuclear - because once all of fossil fuels externalities are priced in - its very attractive pricing wise. But fossil fuels are not going anywhere, and no one (but me) seems to have any great appetite for nuclear construction.
HDThoreaun 3y ago
Heat pumps are much more efficient than furnaces. Even if 100% of the electricity generation was coal you’d use less energy to heat your home with the pump so there’d be less emissions.
- sokoloff 3y ago
  That depends on the outside air temp (OAT)*. At OATs below 30°F, the heat pump is capable to heat the home, but the coefficient of performance might be 2.0 or less. For a fossil fuel plant that might convert fuel to electricity with ~35-40% efficiency, a heat pump with a CoP of 2.0 will be less efficient overall than a 90% gas furnace. * More precisely, on the spread between the OAT and the indoor temp, but since the latter is basically a fixed figure...
- Aloha 3y ago
  This just isn't accurate - you use less electricity yes, but not less energy. 1 kWh of electricity run thru a resistive heater will generate 3412 BTU 1 Ccf of gas contains the equivalent energy as 29 kWh, but will only generate 8.7 kWh when run thru thermal generation (assuming 40% efficiency and 10% transmission losses). If you're just trying to make heat, directly burning the gas will consume much less energy - and make fewer emissions - than gas > electricity > heatpump > heat.
  - HDThoreaun 3y ago
    Why are you talking about a resistive heater? Heat pumps dont make heat, they just move it around.
    - Aloha 3y ago
      If you're trying to compare the caloric content of two forms of energy, knowing what you can get out of the energy by itself is helpful. In the end, the HP will be up to 30% more efficient than strip heat (in my case the crossover point is under 10f where strip heat is cheaper to operate). I built a breakdown chart showing cost per kWh for both heat pump and strip heat, then added gas to it as a comparison.

by Aloha 3y ago

toomuchtodo 3y ago

Right, you're not paying the true cost of that energy [1] [2]. I'm saying, what happens when you have to. That changes market signals, perhaps drastically, assuming the per ton cost of CO2 emitted (which is optimistically ~$50/ton but likely closer to $200/ton, assuming the only two ways to handle emitted carbon are to either not emit it or direct air capture and sequester underground ie Climeworks and company). When consumers must pay for the externalities of their fossil fuel consumption, it's no longer economically competitive. If you can't pass carbon taxes, have to outlaw new gas service like many jurisdictions are attempting to do. High level, looking at the cost of natural gas alone is insufficient for these discussions; you have to look at the entire supply chain and externalities to arrive at a true "apples to apples" comparison. (matters now, but won't as the blended cost of renewables and storage [firm generation] declines below the floor fossil gas needs to sell at to keep the infra running, and that infra already leaks like a sieve [3]) [1] https://energypost.eu/new-u-s-study-damage-per-ton-of-co2-costs-185-not-the-official-51/ https://energypost.eu/new-u-s-study-damage-per-ton-of-co2-co... [2] https://www.nature.com/articles/s41586-022-05224-9 https://www.nature.com/articles/s41586-022-05224-9 [3] https://www.edf.org/climate/methanemaps https://www.edf.org/climate/methanemaps

amluto 3y ago
In a sensible world, i.e. not California IOU-land, you are of course correct. In California, for IOU customers, electric rates are pushing $600/MWh. You can figure out how exactly you want to apply the emission factors: https://www.epa.gov/energy/greenhouse-gases-equivalencies-calculator-calculations-and-references https://www.epa.gov/energy/greenhouse-gases-equivalencies-ca... But you will have a hard time making the math come out in favor of electricity. Unless you have a really nice heat pump, your electricity is 100% carbon-free, and you rule out gas-fired heat pumps [0] or cogen [1], you’re probably better off burning natural gas and using the money you save to offset your carbon usage in some more effective manner than throwing it at your local utility so they can burn it. Fundamentally, carbon pricing can work when CO2 emissions are expensive and the clean alternatives are reasonably priced. California has a major problem with the latter requirement. [0] They exist but seem very rare. [1] Reputable companies make these, but the devices are large and are not friendly for residential installations.
- Aloha 3y ago
  In a parallel comment I ran the numbers - and you're absolutely correct here.
Aloha 3y ago
Even if you price CO2 emissions in, both electricity and natgas rise - because of how much electricity is generated by gas - and how inefficient thermal generation is. 1 metric ton of carbon is about 19 Mcf of gas burned. 19 Mcf of gas contains about 1.65MW of electric power (assuming combined efficiency of generation and transmission of 30% - if you can provide a framework for better electricity efficiency I'm open to it). It'd add about $121 to the price per MW or 35 cents per 10,000 BTU It'd add about $10 to the price per Mcf of gas or about 10 cents per 10,000 BTU Assuming that 50% of your power has a carbon surcharge on it, we can halve those numbers - 17.5 cents per 10,000 BTU. So once I plug those into my HP Calculator - that raises assumed electricity prices to 90 cents per 10,000 BTU and gas prices to 24 cents per 10,000 BTU. The heat pump still ends up being more expensive over the entire operating range - note that HP efficiency goes down with temperature. So at 40f it costs 35 cents on my 5T HP to generate 10,000 BTU of heat, at 10f 65 cents per 10,000 BTU of heat. Gas however is steady at 29 cents per 10,000 BTU of heat - no matter the operating temp.
- itsoktocry 3y ago
  Thank you. The "but fossil fuel externalities!" crew can't seem to comprehend just how efficient, cheap and abundant fossil fuels are, and that we can't simply shut them off or double their price tomorrow without massive economic consequences.
  - Aloha 3y ago
    Bear in mind, I'm pro alternative energy, I'm a major advocate for nuclear - because once all of fossil fuels externalities are priced in - its very attractive pricing wise. But fossil fuels are not going anywhere, and no one (but me) seems to have any great appetite for nuclear construction.

HDThoreaun 3y ago

Heat pumps are much more efficient than furnaces. Even if 100% of the electricity generation was coal you’d use less energy to heat your home with the pump so there’d be less emissions.

sokoloff 3y ago
That depends on the outside air temp (OAT)*. At OATs below 30°F, the heat pump is capable to heat the home, but the coefficient of performance might be 2.0 or less. For a fossil fuel plant that might convert fuel to electricity with ~35-40% efficiency, a heat pump with a CoP of 2.0 will be less efficient overall than a 90% gas furnace. * More precisely, on the spread between the OAT and the indoor temp, but since the latter is basically a fixed figure...
Aloha 3y ago
This just isn't accurate - you use less electricity yes, but not less energy. 1 kWh of electricity run thru a resistive heater will generate 3412 BTU 1 Ccf of gas contains the equivalent energy as 29 kWh, but will only generate 8.7 kWh when run thru thermal generation (assuming 40% efficiency and 10% transmission losses). If you're just trying to make heat, directly burning the gas will consume much less energy - and make fewer emissions - than gas > electricity > heatpump > heat.
- HDThoreaun 3y ago
  Why are you talking about a resistive heater? Heat pumps dont make heat, they just move it around.
  - Aloha 3y ago
    If you're trying to compare the caloric content of two forms of energy, knowing what you can get out of the energy by itself is helpful. In the end, the HP will be up to 30% more efficient than strip heat (in my case the crossover point is under 10f where strip heat is cheaper to operate). I built a breakdown chart showing cost per kWh for both heat pump and strip heat, then added gas to it as a comparison.