6 ms·

That's a valid point but cement and steel production emit CO2 directly, it's not just from the energy source. As part of cement making, "The process of 'calcin

That's a valid point but cement and steel production emit CO2 directly, it's not just from the energy source. As part of cement making, "The process of 'calcination' splits the material into calcium oxide and CO2."[1] About half a ton of CO2 is emitted per ton of cement.[2] And with steel: "The prevailing process makes steel from iron ore — which is mostly iron oxide — by heating it with carbon; the process forms carbon dioxide as a byproduct. Production of a ton of steel generates almost two tons of CO2 emissions."[3] Wind farms use a lot of concrete and steel; by some estimates, more than nuclear.[4] Of course, total emissions is still way less than fossil. Assuming normal lifespan, about 25 lbs of material per MWh[5], so (very) roughly that much CO2. By comparison, a coal plant emits over 2000 lbs CO2 per MWh. [6] [1] https://www.bbc.com/news/science-environment-46455844 https://www.bbc.com/news/science-environment-46455844 [2] https://www.linkedin.com/pulse/co2-emission-from-cement-industry-whats-best-estimate-claude-lorea/ https://www.linkedin.com/pulse/co2-emission-from-cement-indu... [3] https://news.mit.edu/2013/steel-without-greenhouse-gas-emissions-0508 https://news.mit.edu/2013/steel-without-greenhouse-gas-emiss... [4] https://thebreakthrough.org/issues/energy/nuclear-has-one-of-the-smallest-footprints https://thebreakthrough.org/issues/energy/nuclear-has-one-of... [5] https://www.freeingenergy.com/math/wind-turbine-weight-pound-mwh-gwh-m148/ https://www.freeingenergy.com/math/wind-turbine-weight-pound... [6] https://www.epa.gov/sites/production/files/2020-12/documents/power_plants_2017_industrial_profile_updated_2020.pdf https://www.epa.gov/sites/production/files/2020-12/documents...

perl4ever 5y ago
The word "global" in the term "global climate change" means CO2 is fungible. Trying to make every arbitrarily delimited activity carbon neutral on its own sounds like a cult hijacking AGW to me.
- kristopolous 5y ago
  You say fungible, I say aggregate. Here's essentially the problem you're laying out. If I have a house run by solar power and walk to the store to buy fruit from 10,000 miles away to feed to my 5 children, my carbon costs are so astronomically high from the last two that the first two don't matter. I agree! Absolutely! But also, if transporting fruit 10,000 miles could be done with renewables that will zero that out. If by the time the children are adults, significant delimited activity has transformed through say, better agricultural practices, more efficient appliances, better building design to that can regulate temperature better, all these small things, then the aggregate decreases Stop having 5 kids and buying 10,000 mile away fruit, I'm with you. Sure. But the point of this exercise is to make such things not so high cost so that the freedom to do these things, however much I personally disapprove of it, can be preserved. That's one of the things the anti-climate change people don't get. They see the current transformations as a restriction of their liberties. No, it's a massive effort to preserve them. If we fail to transform society and cities start sinking into the sea, I assure you, forced sterilization, meat consumption bans, bans on private car ownership, local only food by law, a ban on air travel, it'll all be on the table. We all saw how quickly the shoe dropped on covid last march; from busy streets to boarded up ghost towns in about 2 weeks. We didn't heed the warnings to prepare and here we are still living with the consequences. Let's stay on top of this one.
  - Robotbeat 5y ago
    If your kids have a negative carbon footprint (this is possible... after all, trees do it... because carbon is a good building material for cell walls), then having more kids is potentially superior to having fewer...
    - ajuc 5y ago
      I don't think kids can do photosynthesis. And I can't imagine any way to make kids carbon negative that wouldn't be considered a crime against humanity.
      - monkeycantype 5y ago
        Kids can plant trees
        ajuc 5y ago
        Planting trees isn't the problem. Trees can plant themselves pretty well already, just leave them space that you won't cut and plow every year. My late grandpa had a small plot of land where he grew tomatoes and other vegetables. Since he died 12 years ago nobody does anything to that land cause he lived far from the rest of the family. It's a small forest now. Not cutting trees for new farming land and leaving the space is the problematic part. And more kids is kinda at odds with this. BTW what you're actually doing by planting a tree is burning carbon to move an already existing plant from one place to another.
        Firadeoclus 5y ago
        > BTW what you're actually doing by planting a tree is burning carbon to move an already existing plant from one place to another. That is true (unless you're actually planting seeds), but generally the idea is that another tree will grow where you took it from, so the end result is more trees.
        5y ago
cjblomqvist 5y ago
Same logic works there as well though, it's possible to fix that, both for steel and cement(see Sweden)
- madspindel 5y ago
  For those interested: https://www.hybritdevelopment.se/en/ https://www.hybritdevelopment.se/en/ https://www.h2greensteel.com/ https://www.h2greensteel.com/ https://www.cementa.se/sv/slite-ccs https://www.cementa.se/sv/slite-ccs
adrianN 5y ago
Steel can also be made in a process using hydrogen instead of coke. I don't know any replacements for cement.
- msandford 5y ago
  There are folks talking about using solar concentrators (like solar thermal plants) but without the steam turbine and electrical generation equipment to make cement. https://helioscsp.com/concentrated-solar-power-csp-and-industrial-processes/ https://helioscsp.com/concentrated-solar-power-csp-and-indus...
- kragen 5y ago
  There are a number of replacements for (ordinary Portland) cement, such as slaked lime, Sorel cement, alkali-activated cement, geopolymer cement (sometimes classed as an alkali-activated cement, though the Geopolymer Institute disagrees), and so on. Most of these have lower, zero, or even negative net CO₂ emissions. https://res.mdpi.com/d_attachment/sustainability/sustainability-11-00537/article_deploy/sustainability-11-00537.pdf https://res.mdpi.com/d_attachment/sustainability/sustainabil... "Recent Progress in Green Cement Technology Utilizing Low-Carbon Emission Fuels and Raw Materials: A Review" is a CC-BY overview of seven of them from 02019.
Robotbeat 5y ago
Steel in particular in new plants in the US, the stuff that isn't recycled in arc furnaces, is being made with a mix of hydrogen and CO (both from natural gas), and there's no reason the mix can't be almost entirely hydrogen (only a token amount of carbon is needed, and some of that ends up in the steel). Direct reduced iron furnaces can be converted to run almost entirely on hydrogen. Cement DOES emit CO2 during manufacture, but it also absorbs it during cure (which, granted, can take decades). That means you can potentially use it for direct air capture in a sort of indirect way. (i.e. you capture the CO2 emitted during calcination, when the CO2 is very concentrated and easy to capture, then the cement itself captures CO2 directly from the air during cure).
- DennisP 5y ago
  I've been doing some googling and it appears that the US isn't actually building new steel plants. The only capacity increase I could find was bringing old plants back online. All the old stuff (other than recycling) uses carbon. Do you have a link showing what I missed? US Steel has started to look into hydrogen production, but hasn't built anything yet. [0] Europe has some pilot projects for hydrogen-produced steel but nothing operational. [1] We certainly should make that conversion, and also ensure that we use green hydrogen for it, but that's a big change and there won't be much economic incentive for it before we have a decent carbon price. "Renewable hydrogen-based iron production can become the least-cost supply option at a carbon dioxide (CO2) price of around United States dollars (USD) 67 per tonne," but "the hydrogen energy used would equal 1% of global primary energy supply." [2] Carbon capture during cement production of course also lacks economic incentive until we have a carbon price, but I haven't found a specific price it would need. [0] https://www.reuters.com/business/energy/us-steel-norways-equinor-eye-clean-hydrogen-production-2021-06-29/ https://www.reuters.com/business/energy/us-steel-norways-equ... [1] https://bellona.org/news/industrial-pollution/2021-05-hydrogen-in-steel-production-what-is-happening-in-europe-part-two https://bellona.org/news/industrial-pollution/2021-05-hydrog... [2] https://onlinelibrary.wiley.com/doi/full/10.1111/jiec.12997 https://onlinelibrary.wiley.com/doi/full/10.1111/jiec.12997
  - Robotbeat 5y ago

perl4ever 5y ago

The word "global" in the term "global climate change" means CO2 is fungible. Trying to make every arbitrarily delimited activity carbon neutral on its own sounds like a cult hijacking AGW to me.

kristopolous 5y ago
You say fungible, I say aggregate. Here's essentially the problem you're laying out. If I have a house run by solar power and walk to the store to buy fruit from 10,000 miles away to feed to my 5 children, my carbon costs are so astronomically high from the last two that the first two don't matter. I agree! Absolutely! But also, if transporting fruit 10,000 miles could be done with renewables that will zero that out. If by the time the children are adults, significant delimited activity has transformed through say, better agricultural practices, more efficient appliances, better building design to that can regulate temperature better, all these small things, then the aggregate decreases Stop having 5 kids and buying 10,000 mile away fruit, I'm with you. Sure. But the point of this exercise is to make such things not so high cost so that the freedom to do these things, however much I personally disapprove of it, can be preserved. That's one of the things the anti-climate change people don't get. They see the current transformations as a restriction of their liberties. No, it's a massive effort to preserve them. If we fail to transform society and cities start sinking into the sea, I assure you, forced sterilization, meat consumption bans, bans on private car ownership, local only food by law, a ban on air travel, it'll all be on the table. We all saw how quickly the shoe dropped on covid last march; from busy streets to boarded up ghost towns in about 2 weeks. We didn't heed the warnings to prepare and here we are still living with the consequences. Let's stay on top of this one.
- Robotbeat 5y ago
  If your kids have a negative carbon footprint (this is possible... after all, trees do it... because carbon is a good building material for cell walls), then having more kids is potentially superior to having fewer...
  - ajuc 5y ago
    I don't think kids can do photosynthesis. And I can't imagine any way to make kids carbon negative that wouldn't be considered a crime against humanity.
    - monkeycantype 5y ago
      Kids can plant trees
      - ajuc 5y ago
        Planting trees isn't the problem. Trees can plant themselves pretty well already, just leave them space that you won't cut and plow every year. My late grandpa had a small plot of land where he grew tomatoes and other vegetables. Since he died 12 years ago nobody does anything to that land cause he lived far from the rest of the family. It's a small forest now. Not cutting trees for new farming land and leaving the space is the problematic part. And more kids is kinda at odds with this. BTW what you're actually doing by planting a tree is burning carbon to move an already existing plant from one place to another.
        Firadeoclus 5y ago
        > BTW what you're actually doing by planting a tree is burning carbon to move an already existing plant from one place to another. That is true (unless you're actually planting seeds), but generally the idea is that another tree will grow where you took it from, so the end result is more trees.
        5y ago

cjblomqvist 5y ago

Same logic works there as well though, it's possible to fix that, both for steel and cement(see Sweden)

madspindel 5y ago
For those interested: https://www.hybritdevelopment.se/en/ https://www.hybritdevelopment.se/en/ https://www.h2greensteel.com/ https://www.h2greensteel.com/ https://www.cementa.se/sv/slite-ccs https://www.cementa.se/sv/slite-ccs

adrianN 5y ago

Steel can also be made in a process using hydrogen instead of coke. I don't know any replacements for cement.

msandford 5y ago
There are folks talking about using solar concentrators (like solar thermal plants) but without the steam turbine and electrical generation equipment to make cement. https://helioscsp.com/concentrated-solar-power-csp-and-industrial-processes/ https://helioscsp.com/concentrated-solar-power-csp-and-indus...
kragen 5y ago
There are a number of replacements for (ordinary Portland) cement, such as slaked lime, Sorel cement, alkali-activated cement, geopolymer cement (sometimes classed as an alkali-activated cement, though the Geopolymer Institute disagrees), and so on. Most of these have lower, zero, or even negative net CO₂ emissions. https://res.mdpi.com/d_attachment/sustainability/sustainability-11-00537/article_deploy/sustainability-11-00537.pdf https://res.mdpi.com/d_attachment/sustainability/sustainabil... "Recent Progress in Green Cement Technology Utilizing Low-Carbon Emission Fuels and Raw Materials: A Review" is a CC-BY overview of seven of them from 02019.

Robotbeat 5y ago

Steel in particular in new plants in the US, the stuff that isn't recycled in arc furnaces, is being made with a mix of hydrogen and CO (both from natural gas), and there's no reason the mix can't be almost entirely hydrogen (only a token amount of carbon is needed, and some of that ends up in the steel). Direct reduced iron furnaces can be converted to run almost entirely on hydrogen. Cement DOES emit CO2 during manufacture, but it also absorbs it during cure (which, granted, can take decades). That means you can potentially use it for direct air capture in a sort of indirect way. (i.e. you capture the CO2 emitted during calcination, when the CO2 is very concentrated and easy to capture, then the cement itself captures CO2 directly from the air during cure).

DennisP 5y ago
I've been doing some googling and it appears that the US isn't actually building new steel plants. The only capacity increase I could find was bringing old plants back online. All the old stuff (other than recycling) uses carbon. Do you have a link showing what I missed? US Steel has started to look into hydrogen production, but hasn't built anything yet. [0] Europe has some pilot projects for hydrogen-produced steel but nothing operational. [1] We certainly should make that conversion, and also ensure that we use green hydrogen for it, but that's a big change and there won't be much economic incentive for it before we have a decent carbon price. "Renewable hydrogen-based iron production can become the least-cost supply option at a carbon dioxide (CO2) price of around United States dollars (USD) 67 per tonne," but "the hydrogen energy used would equal 1% of global primary energy supply." [2] Carbon capture during cement production of course also lacks economic incentive until we have a carbon price, but I haven't found a specific price it would need. [0] https://www.reuters.com/business/energy/us-steel-norways-equinor-eye-clean-hydrogen-production-2021-06-29/ https://www.reuters.com/business/energy/us-steel-norways-equ... [1] https://bellona.org/news/industrial-pollution/2021-05-hydrogen-in-steel-production-what-is-happening-in-europe-part-two https://bellona.org/news/industrial-pollution/2021-05-hydrog... [2] https://onlinelibrary.wiley.com/doi/full/10.1111/jiec.12997 https://onlinelibrary.wiley.com/doi/full/10.1111/jiec.12997
- Robotbeat 5y ago