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Is there an actual possibility of burning coal in a”clean way” through any technology now or in the future? The current term “clean coal” is obviously BS, but

by hodder 7y ago

Is there an actual possibility of burning coal in a”clean way” through any technology now or in the future? The current term “clean coal” is obviously BS, but is it possible either now or in the future, but just uneconomic? It is an immense resource if we could extract the energy of coal in a clean way.

sonnyblarney 7y ago
No so much coal, persey, but it's not unfeasible to capture the CO2 emitted by burning coal (or whatever) and sequester it in the ground. This should be talked about more because it enables us to use all that energy, but I suggest there might be ugly political connotations around it, much like Nuclear.
- colechristensen 7y ago
  https://en.wiktionary.org/wiki/per_se https://en.wiktionary.org/wiki/per_se
- maxxxxx 7y ago
  Are there any proposals for making this possible on the required scale in an economical way? I don't think so.
  - sonnyblarney 7y ago
    I'm not hugely familiar with it, other than I know that it's definitely something under consideration and though not yet feasible , it satisfies the query of the OP, i.e. it's 'an opportunity to make use of carbon fuels with no emissions' I wish people who'd down vote my comment would reply if there is a factual error or misrepresentation of some kind on my part.
    - danans 7y ago
      From: https://en.wikipedia.org/wiki/Carbon_capture_and_storage#Cost https://en.wikipedia.org/wiki/Carbon_capture_and_storage#Cos... "The reasons that CCS is expected to cause such power price increases are several. Firstly, the increased energy requirements of capturing and compressing CO 2 significantly raises the operating costs of CCS-equipped power plants. In addition, there are added investment and capital costs. The process would increase the fuel requirement of a plant with CCS by about 25% for a coal-fired plant" This is on top of the new reality that building solar and wind is cheaper than the cost to just operate existing coal plants [1], and therefore far cheaper than building new coal plants or retrofitting old coal plants with expensive (both CapEx and OpEx) CCS systems. 1. https://www.forbes.com/sites/energyinnovation/2018/12/03/plunging-prices-mean-building-new-renewable-energy-is-cheaper-than-running-existing-coal/#1eb59a2d31f3 https://www.forbes.com/sites/energyinnovation/2018/12/03/plu... "[The C02 sequestration process steals] up to 30% of the energy produced by a coal-fired power plant, reducing its efficiency and raising its electricity price. Second-generation facilities capture and reuse waste heat, among other things, but their costs are still too high, Brickett says."
      - sonnyblarney 7y ago
        I'm aware of all of that, and that it's not feasible 'today', but: a) Solar was 'not feasible' only 10 years ago, with more innovation and otherwise more expensive prices, it's feasible in some scenarios. There's no reason we can't innovate along other vectors. If the operating costs of solar can be reduced, surely they can with carbon fuel plants as well. b) My point was specifically regarding burning any carbon fuel, not just coal. Natural Gas is by far the cheapest way to make electricity (depending on how you amortize Hydro I think), so 'Carbon Sequestration' would be a massive opportunity. Why would we ignore it? c) A '30% cost increase' is actually pretty small considering most other alternatives and issues. In fact, that's good news because most energy schemes are not remotely feasible - if some clean energy scheme were only '30% away from being competitive' we'd be celebrating. If we could save the planet merely by raising electricity costs by 30% that would probably be a viable plan, globally. d) There are places that exist 'outside the US' - like Canada, where way up north there isn't nearly as much sunlight, and the days are exceedingly short in winter, and this changes the nature of the electricity equation quite a lot and it's not actually feasible, and neither is wind in many places. e) Carbon fuels burn in a predictable manner, which has all sorts of utility beyond the simple price. Something you can plan for is considerably more valuable than something that's inherently variable, so much so that in many cases the 'variable power' has little utility. Particularly given there's tons of carbon fuels in the ground, I don't see why people would be against sequestration as long as it actually works.
        danans 7y ago
        > Particularly given there's tons of carbon fuels in the ground, I don't see why people would be against sequestration as long as it actually works. Nobody is against anyone trying, but people are entitled to their doubts. If there were significant potential in CCS, investment dollars would respond accordingly. So far the results haven't gotten anywhere near the value proposition offered by renewables, especially in OpEx. Maybe that will change, maybe it won't.
stephen_g 7y ago
I think in general no. Even high quality coal has huge amounts of impurities, and coal in general is hugely variable in quality. Even with scrubbers etc. removing ash etc. you pump all sorts of dangerous emissions as well as the huge amount of CO2. There exist “high efficiency low emissions” (HELE) coal stations, but that moniker is only true in relation to conventional coal stations. They’re still some of the dirtiest generation we have. From the experience of the ones we have in Australia, they appear to be more unreliable in hot weather than older coal plants too - I believe probably because they would operate at higher temperature/pressures to improve efficiency.
- dreamcompiler 7y ago
  Coal plants produce a lot of airborne radioactive compounds too -- vastly more than nuclear plants* and I don't know if scrubbers fix that problem. If they did, there would still be the problem of disposing of mixed waste from the scrubbers themselves. *Citation not handy but easily googleable.
  - v_lisivka 7y ago
    Ok, I googled it: https://nuclear-news.net/2015/11/27/coal-ash-is-not-more-radioactive-than-nuclear-waste/ https://nuclear-news.net/2015/11/27/coal-ash-is-not-more-rad...
  - amenod 7y ago
    Just to say it explicitly - the problem with nuclear plants is not radioactivity while they operate normally. It is the catastrophic consequences then something goes (really) wrong that are the real issue with them.
    - dreamcompiler 7y ago
      Yes. Plus eventual waste disposal.
      - amenod 7y ago
mensetmanusman 7y ago
Actual possibility? Yes. Filtration is good enough that it could technically capture everything. Technically you could plant enough trees to capture all the CO2 as well. The energy required to make all the filters and plant and maintain all the trees might be greater than the energy produced by coal though, and that is the issue.
- CydeWeys 7y ago
  The whole "plant trees" thing doesn't work too well because you'll run out of space long before you run out of hydrocarbons to dig up and burn. Plus, the trees need to stay standing; if at any point they're cut and burnt, or die and decay, then all the CO2 is released again. CO2 buried underground in the form of coal or oil is a much better long-term storage solution for CO2 than trees up on the surface. The logical thing to do would be to start burying CO2, not continue digging it up and releasing it.
  - perilunar 7y ago
    > the trees need to stay standing No they don't. They need to be harvested and used for timber products, where the carbon can stay locked in for decades or longer. The land can then be replanted for more carbon removal. Ideally you would use trees to make engineered wood products that replace steel and concrete, the production of which also release large amounts of CO2.
    - addicted 7y ago
      That assumes that young trees and forests have the same carbon capturing efficiencies, when I believe it’s older trees and forests that have significantly greater carbon absorbing capabilities.
      - npongratz 7y ago
        I'm unfamiliar with the quality of this publication, but it reports on a study suggesting younger forests are better at carbon dioxide sequestration than older forests: https://psmag.com/environment/young-trees-suck-up-more-carbon-than-old-ones https://psmag.com/environment/young-trees-suck-up-more-carbo... 'Tropical rainforests, the revered "lungs of the planet," were once thought to take the cake when it comes to carbon sequestration. But a new study adds to a growing body of evidence that other types of forest may actually be better at sucking CO2 out of the atmosphere. Specifically it finds that young temperate forests may be more effective carbon sinks than are old rainforests.'
Joakal 7y ago
Yes. Burn it inside building and capture CO2. As it stands, the gas waste is externalised. Imagine if nuclear reactors were allowed to dump waste in air/river.
- CydeWeys 7y ago
  And do what with the CO2? Burning coal releases a lot of it.
  - toss1 7y ago
    Capture it and bury it underground turning it into rock https://phys.org/news/2019-05-iceland-carbon-dioxide-cleaner-air.html https://phys.org/news/2019-05-iceland-carbon-dioxide-cleaner... Capture it and convert it to fuel https://phys.org/news/2018-10-catalyst-door-carbon-dioxide-capture.html https://phys.org/news/2018-10-catalyst-door-carbon-dioxide-c... Capture it and convert it to plastics https://phys.org/news/2018-11-co2-ingredients-fuel-plastics-food.html https://phys.org/news/2018-11-co2-ingredients-fuel-plastics-... etc...
    - neuronic 7y ago
      The fact that none of this is economical makes this fairly difficult to do.
      - yellow_postit 7y ago
        “Economical” evaluation right now, in the US, is before the true cost of carbon emissions are priced in. Once/If there’s a real carbon tax the economic viability on these may change. I personally believe that in addition to pricing carbon governments are going to have to self fund massive sequestration projects as well to avoid catastrophic change.
    - happosai 7y ago
      Which none make any sense since capturing and converting co2 consumes more energy than burning the coal generated.
justnoise 7y ago
A demonstration power plant based on the Allam cycle [1] is being tested in Texas. In that process the CO2 is captured while achieving efficiencies that come close to conventional power plants. The plant in Texas burns natural gas but the Allam cycle can also run on gassified coal. [1] https://en.m.wikipedia.org/wiki/Allam_power_cycle https://en.m.wikipedia.org/wiki/Allam_power_cycle

by hodder 7y ago

sonnyblarney 7y ago

No so much coal, persey, but it's not unfeasible to capture the CO2 emitted by burning coal (or whatever) and sequester it in the ground. This should be talked about more because it enables us to use all that energy, but I suggest there might be ugly political connotations around it, much like Nuclear.

colechristensen 7y ago
https://en.wiktionary.org/wiki/per_se https://en.wiktionary.org/wiki/per_se
maxxxxx 7y ago
Are there any proposals for making this possible on the required scale in an economical way? I don't think so.
- sonnyblarney 7y ago
  I'm not hugely familiar with it, other than I know that it's definitely something under consideration and though not yet feasible , it satisfies the query of the OP, i.e. it's 'an opportunity to make use of carbon fuels with no emissions' I wish people who'd down vote my comment would reply if there is a factual error or misrepresentation of some kind on my part.
  - danans 7y ago
    From: https://en.wikipedia.org/wiki/Carbon_capture_and_storage#Cost https://en.wikipedia.org/wiki/Carbon_capture_and_storage#Cos... "The reasons that CCS is expected to cause such power price increases are several. Firstly, the increased energy requirements of capturing and compressing CO 2 significantly raises the operating costs of CCS-equipped power plants. In addition, there are added investment and capital costs. The process would increase the fuel requirement of a plant with CCS by about 25% for a coal-fired plant" This is on top of the new reality that building solar and wind is cheaper than the cost to just operate existing coal plants [1], and therefore far cheaper than building new coal plants or retrofitting old coal plants with expensive (both CapEx and OpEx) CCS systems. 1. https://www.forbes.com/sites/energyinnovation/2018/12/03/plunging-prices-mean-building-new-renewable-energy-is-cheaper-than-running-existing-coal/#1eb59a2d31f3 https://www.forbes.com/sites/energyinnovation/2018/12/03/plu... "[The C02 sequestration process steals] up to 30% of the energy produced by a coal-fired power plant, reducing its efficiency and raising its electricity price. Second-generation facilities capture and reuse waste heat, among other things, but their costs are still too high, Brickett says."
    - sonnyblarney 7y ago
      I'm aware of all of that, and that it's not feasible 'today', but: a) Solar was 'not feasible' only 10 years ago, with more innovation and otherwise more expensive prices, it's feasible in some scenarios. There's no reason we can't innovate along other vectors. If the operating costs of solar can be reduced, surely they can with carbon fuel plants as well. b) My point was specifically regarding burning any carbon fuel, not just coal. Natural Gas is by far the cheapest way to make electricity (depending on how you amortize Hydro I think), so 'Carbon Sequestration' would be a massive opportunity. Why would we ignore it? c) A '30% cost increase' is actually pretty small considering most other alternatives and issues. In fact, that's good news because most energy schemes are not remotely feasible - if some clean energy scheme were only '30% away from being competitive' we'd be celebrating. If we could save the planet merely by raising electricity costs by 30% that would probably be a viable plan, globally. d) There are places that exist 'outside the US' - like Canada, where way up north there isn't nearly as much sunlight, and the days are exceedingly short in winter, and this changes the nature of the electricity equation quite a lot and it's not actually feasible, and neither is wind in many places. e) Carbon fuels burn in a predictable manner, which has all sorts of utility beyond the simple price. Something you can plan for is considerably more valuable than something that's inherently variable, so much so that in many cases the 'variable power' has little utility. Particularly given there's tons of carbon fuels in the ground, I don't see why people would be against sequestration as long as it actually works.
      - danans 7y ago
        > Particularly given there's tons of carbon fuels in the ground, I don't see why people would be against sequestration as long as it actually works. Nobody is against anyone trying, but people are entitled to their doubts. If there were significant potential in CCS, investment dollars would respond accordingly. So far the results haven't gotten anywhere near the value proposition offered by renewables, especially in OpEx. Maybe that will change, maybe it won't.

stephen_g 7y ago

I think in general no. Even high quality coal has huge amounts of impurities, and coal in general is hugely variable in quality. Even with scrubbers etc. removing ash etc. you pump all sorts of dangerous emissions as well as the huge amount of CO2. There exist “high efficiency low emissions” (HELE) coal stations, but that moniker is only true in relation to conventional coal stations. They’re still some of the dirtiest generation we have. From the experience of the ones we have in Australia, they appear to be more unreliable in hot weather than older coal plants too - I believe probably because they would operate at higher temperature/pressures to improve efficiency.

dreamcompiler 7y ago
Coal plants produce a lot of airborne radioactive compounds too -- vastly more than nuclear plants* and I don't know if scrubbers fix that problem. If they did, there would still be the problem of disposing of mixed waste from the scrubbers themselves. *Citation not handy but easily googleable.
- v_lisivka 7y ago
  Ok, I googled it: https://nuclear-news.net/2015/11/27/coal-ash-is-not-more-radioactive-than-nuclear-waste/ https://nuclear-news.net/2015/11/27/coal-ash-is-not-more-rad...
- amenod 7y ago
  Just to say it explicitly - the problem with nuclear plants is not radioactivity while they operate normally. It is the catastrophic consequences then something goes (really) wrong that are the real issue with them.
  - dreamcompiler 7y ago
    Yes. Plus eventual waste disposal.
    - amenod 7y ago

mensetmanusman 7y ago

Actual possibility? Yes. Filtration is good enough that it could technically capture everything. Technically you could plant enough trees to capture all the CO2 as well. The energy required to make all the filters and plant and maintain all the trees might be greater than the energy produced by coal though, and that is the issue.

CydeWeys 7y ago
The whole "plant trees" thing doesn't work too well because you'll run out of space long before you run out of hydrocarbons to dig up and burn. Plus, the trees need to stay standing; if at any point they're cut and burnt, or die and decay, then all the CO2 is released again. CO2 buried underground in the form of coal or oil is a much better long-term storage solution for CO2 than trees up on the surface. The logical thing to do would be to start burying CO2, not continue digging it up and releasing it.
- perilunar 7y ago
  > the trees need to stay standing No they don't. They need to be harvested and used for timber products, where the carbon can stay locked in for decades or longer. The land can then be replanted for more carbon removal. Ideally you would use trees to make engineered wood products that replace steel and concrete, the production of which also release large amounts of CO2.
  - addicted 7y ago
    That assumes that young trees and forests have the same carbon capturing efficiencies, when I believe it’s older trees and forests that have significantly greater carbon absorbing capabilities.
    - npongratz 7y ago
      I'm unfamiliar with the quality of this publication, but it reports on a study suggesting younger forests are better at carbon dioxide sequestration than older forests: https://psmag.com/environment/young-trees-suck-up-more-carbon-than-old-ones https://psmag.com/environment/young-trees-suck-up-more-carbo... 'Tropical rainforests, the revered "lungs of the planet," were once thought to take the cake when it comes to carbon sequestration. But a new study adds to a growing body of evidence that other types of forest may actually be better at sucking CO2 out of the atmosphere. Specifically it finds that young temperate forests may be more effective carbon sinks than are old rainforests.'

Joakal 7y ago

Yes. Burn it inside building and capture CO2. As it stands, the gas waste is externalised. Imagine if nuclear reactors were allowed to dump waste in air/river.

CydeWeys 7y ago
And do what with the CO2? Burning coal releases a lot of it.
- toss1 7y ago
  Capture it and bury it underground turning it into rock https://phys.org/news/2019-05-iceland-carbon-dioxide-cleaner-air.html https://phys.org/news/2019-05-iceland-carbon-dioxide-cleaner... Capture it and convert it to fuel https://phys.org/news/2018-10-catalyst-door-carbon-dioxide-capture.html https://phys.org/news/2018-10-catalyst-door-carbon-dioxide-c... Capture it and convert it to plastics https://phys.org/news/2018-11-co2-ingredients-fuel-plastics-food.html https://phys.org/news/2018-11-co2-ingredients-fuel-plastics-... etc...
  - neuronic 7y ago
    The fact that none of this is economical makes this fairly difficult to do.
    - yellow_postit 7y ago
      “Economical” evaluation right now, in the US, is before the true cost of carbon emissions are priced in. Once/If there’s a real carbon tax the economic viability on these may change. I personally believe that in addition to pricing carbon governments are going to have to self fund massive sequestration projects as well to avoid catastrophic change.
  - happosai 7y ago
    Which none make any sense since capturing and converting co2 consumes more energy than burning the coal generated.

justnoise 7y ago

A demonstration power plant based on the Allam cycle [1] is being tested in Texas. In that process the CO2 is captured while achieving efficiencies that come close to conventional power plants. The plant in Texas burns natural gas but the Allam cycle can also run on gassified coal. [1] https://en.m.wikipedia.org/wiki/Allam_power_cycle https://en.m.wikipedia.org/wiki/Allam_power_cycle