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There are no existing viable carbon capture technologies that can help deal with the scale of global carbon emission. It's a cool idea, and maybe one day might

There are no existing viable carbon capture technologies that can help deal with the scale of global carbon emission. It's a cool idea, and maybe one day might be able to contribute to resolving GHGs. MIGHT be able to. We don't know if such technology will ever be feasible at scale.

credit_guy 3y ago
Why not? One molecule of CH4 produces exactly one molecule of CO2 when burned. Not more, not less. A mole of any gas occupies the same volume, about 22.4 liters. If you pump all the CO2 produced in the gas field you extracted the methane from, it's a one to one replacement. Since the natural gas could stay there for many millions of years, the CO2 could also stay there for some millions of years. I personally can't identify a fundamental technological reason why carbon sequestration could not be done at scale. Why do you think it would not work? Obviously, right now it does not work because why would it? There is no incentive. But if we put a tax on carbon emissions, then I don't see why carbon sequestration could not be a scalable solution. [1] https://www.eia.gov/todayinenergy/detail.php?id=46676 https://www.eia.gov/todayinenergy/detail.php?id=46676
- danans 3y ago
  > If you pump all the CO2 produced in the gas field you extracted the methane from, it's a one to one replacement. Perhaps I'm misunderstanding your phrasing, but the vast majority of the CO2 released from natural gas comes from its combustion in its end use case, not incidental CO2 released during extraction from a particular field. > Obviously, right now it does not work because why would it? There is no incentive. But if we put a tax on carbon emissions, then I don't see why carbon sequestration could not be a scalable solution. Right now most CO2 removal and sequestration requires large amounts of zero carbon electricity. That electricity is quite expensive on the wholesale markets at the moment, due in no small part to the high marginal cost of fossil fuels, which set the wholesale price of electricity. A carbon tax would certainly help the economics of carbon capture, but until wholesale electricity prices consistently are far lower and DAC technology lowers in cost, it won't be viable on its own. The Kern project is doing at least one thing right by using their own utility scale solar farm. I'd guess this is to insulate themselves from dependency on volatile electricity prices.
  - credit_guy 3y ago
    > Perhaps I'm misunderstanding your phrasing, but the vast majority of the CO2 released from natural gas comes from its combustion in its end use case, not incidental CO2 released during extraction from a particular field. The vast majority of methane is burned in power plants. The CO2 can be captured at the stack, and pumped into the ground. If one million m3 of methane is burned, exactly one million m3 of CO2 is produced, not more, not less. It does not take a lot of energy to capture the CO2 from the smoke at the power plant. It may take a lot to capture it from the air, where it's very diffuse, but the smoke at the power plant is just CO2, N2 and water vapor. The N2 can be taken out of the equation by oxy-fuel combustion [1]. Adding carbon sequestration to a power plant is expensive, so one wouldn't do it without some carbon tax incentives. But it's not exorbitant. To be specific, the EIA did a study on the capital cost of various power sources [2], and here's their results: - coal without sequestration: $3700/kW; with sequestration $5900/kW - nat gas without sequestration: $1000/kW; with sequestration $2500/kW - wind: onshore $1300/kW, offshore $4400/kW - solar with 4h battery storage: $1800/kW Coal seems to be out of contention, no matter what subsidies you add. But natural gas power plants with sequestration are not that bad. The price of solar and wind is obviously contingent on location. Solar is not going to be very competitive in Maine, for example. So natural gas with sequestration at $2500/kW is definitely an option vs solar at $1800/kW if the location is not California, Arizona or Texas. But why would anyone consider this as of now, if they can just do it for $1000/kW? If the government changes the incentives though, I don't see why large scale carbon sequestration would not be viable. [1] https://en.wikipedia.org/wiki/Oxy-fuel_combustion_process https://en.wikipedia.org/wiki/Oxy-fuel_combustion_process [2] https://www.eia.gov/analysis/studies/powerplants/capitalcost/pdf/capital_cost_AEO2020.pdf https://www.eia.gov/analysis/studies/powerplants/capitalcost...
    - danans 3y ago
      > To be specific, the EIA did a study on the capital cost of various power sources [2], and here's their results: That is just the capital costs, not the operational (fuel) costs, which are significant for natural gas plants and insignificant for zero carbon sources. The full costs are expressed by LCOE. > If the government changes the incentives though, I don't see why large scale carbon sequestration would not be viable. A tax on greenhouse gas emissions would incentivize carbon free sources of electricity like renewables, storage and nuclear just as much if not more than CCS, because CCS has a max capture rate of 90% so there is a nearly 10% disadvantage out the gate. The only way CCS wins is if its levelized cost for firm energy is lower than all the zero carbon alternatives, regardless of a carbon tax. It might be economical for natural gas powered peaker plants, which fill in supply gaps and sell power at very high prices. However, these run for very short periods so therefore the technology has to be relatively cheap up front in order for the economics to work out.
tuatoru 3y ago
This is incorrect. Accelerated weathering of olivine can do the job, even powered by diesel and coal, for about trillion in capital costs and a trillion a year in running costs. That's one percent of world GDP. All the technologies involved are standard rock mining and pulverizing stuff that has been in use for many decades. The downside, of course, is blanketing parts of shallow seas with rock flour.

credit_guy 3y ago

Why not? One molecule of CH4 produces exactly one molecule of CO2 when burned. Not more, not less. A mole of any gas occupies the same volume, about 22.4 liters. If you pump all the CO2 produced in the gas field you extracted the methane from, it's a one to one replacement. Since the natural gas could stay there for many millions of years, the CO2 could also stay there for some millions of years. I personally can't identify a fundamental technological reason why carbon sequestration could not be done at scale. Why do you think it would not work? Obviously, right now it does not work because why would it? There is no incentive. But if we put a tax on carbon emissions, then I don't see why carbon sequestration could not be a scalable solution. [1] https://www.eia.gov/todayinenergy/detail.php?id=46676 https://www.eia.gov/todayinenergy/detail.php?id=46676

danans 3y ago
> If you pump all the CO2 produced in the gas field you extracted the methane from, it's a one to one replacement. Perhaps I'm misunderstanding your phrasing, but the vast majority of the CO2 released from natural gas comes from its combustion in its end use case, not incidental CO2 released during extraction from a particular field. > Obviously, right now it does not work because why would it? There is no incentive. But if we put a tax on carbon emissions, then I don't see why carbon sequestration could not be a scalable solution. Right now most CO2 removal and sequestration requires large amounts of zero carbon electricity. That electricity is quite expensive on the wholesale markets at the moment, due in no small part to the high marginal cost of fossil fuels, which set the wholesale price of electricity. A carbon tax would certainly help the economics of carbon capture, but until wholesale electricity prices consistently are far lower and DAC technology lowers in cost, it won't be viable on its own. The Kern project is doing at least one thing right by using their own utility scale solar farm. I'd guess this is to insulate themselves from dependency on volatile electricity prices.
- credit_guy 3y ago
  > Perhaps I'm misunderstanding your phrasing, but the vast majority of the CO2 released from natural gas comes from its combustion in its end use case, not incidental CO2 released during extraction from a particular field. The vast majority of methane is burned in power plants. The CO2 can be captured at the stack, and pumped into the ground. If one million m3 of methane is burned, exactly one million m3 of CO2 is produced, not more, not less. It does not take a lot of energy to capture the CO2 from the smoke at the power plant. It may take a lot to capture it from the air, where it's very diffuse, but the smoke at the power plant is just CO2, N2 and water vapor. The N2 can be taken out of the equation by oxy-fuel combustion [1]. Adding carbon sequestration to a power plant is expensive, so one wouldn't do it without some carbon tax incentives. But it's not exorbitant. To be specific, the EIA did a study on the capital cost of various power sources [2], and here's their results: - coal without sequestration: $3700/kW; with sequestration $5900/kW - nat gas without sequestration: $1000/kW; with sequestration $2500/kW - wind: onshore $1300/kW, offshore $4400/kW - solar with 4h battery storage: $1800/kW Coal seems to be out of contention, no matter what subsidies you add. But natural gas power plants with sequestration are not that bad. The price of solar and wind is obviously contingent on location. Solar is not going to be very competitive in Maine, for example. So natural gas with sequestration at $2500/kW is definitely an option vs solar at $1800/kW if the location is not California, Arizona or Texas. But why would anyone consider this as of now, if they can just do it for $1000/kW? If the government changes the incentives though, I don't see why large scale carbon sequestration would not be viable. [1] https://en.wikipedia.org/wiki/Oxy-fuel_combustion_process https://en.wikipedia.org/wiki/Oxy-fuel_combustion_process [2] https://www.eia.gov/analysis/studies/powerplants/capitalcost/pdf/capital_cost_AEO2020.pdf https://www.eia.gov/analysis/studies/powerplants/capitalcost...
  - danans 3y ago
    > To be specific, the EIA did a study on the capital cost of various power sources [2], and here's their results: That is just the capital costs, not the operational (fuel) costs, which are significant for natural gas plants and insignificant for zero carbon sources. The full costs are expressed by LCOE. > If the government changes the incentives though, I don't see why large scale carbon sequestration would not be viable. A tax on greenhouse gas emissions would incentivize carbon free sources of electricity like renewables, storage and nuclear just as much if not more than CCS, because CCS has a max capture rate of 90% so there is a nearly 10% disadvantage out the gate. The only way CCS wins is if its levelized cost for firm energy is lower than all the zero carbon alternatives, regardless of a carbon tax. It might be economical for natural gas powered peaker plants, which fill in supply gaps and sell power at very high prices. However, these run for very short periods so therefore the technology has to be relatively cheap up front in order for the economics to work out.

tuatoru 3y ago

This is incorrect. Accelerated weathering of olivine can do the job, even powered by diesel and coal, for about trillion in capital costs and a trillion a year in running costs. That's one percent of world GDP. All the technologies involved are standard rock mining and pulverizing stuff that has been in use for many decades. The downside, of course, is blanketing parts of shallow seas with rock flour.