7 ms·

Yes, but carbon costs come from burning fossil fuels. If you don't burn fossil fuels to drill wells or build PV panels, then those don't have an embodied life-c

by emtel 5y ago

Yes, but carbon costs come from burning fossil fuels. If you don't burn fossil fuels to drill wells or build PV panels, then those don't have an embodied life-cycle carbon cost. I'm being a bit pedantic, but I think its an important point: The life-cycle carbon cost of renewables isn't a fact about renewables. It's a fact about our current energy production mix, which renewables themselves will change over time.

imtringued 5y ago
You can probably do "time" arbitrage here. The CO2 price is low today so CO2 intensive construction is still viable today but it won't be in the future. Thus your geothermal plant will end up becoming more profitable over time.
kristopolous 5y ago
> The life-cycle carbon cost of renewables isn't a fact about renewables. It's a fact about our current energy production mix, which renewables themselves will change over time. Sure but we are talking about right now. Things will eventually be swapped out. That's a different conversation though, it's an advocacy and not a descriptive one. People tend to use things that are marginally adequate way longer than anyone intended. For instance, the ancient Roman gravity dam of Proserpina is still doing its job. Even if we had say a sleek $1,000 self driving solar car that never needs charging and goes for a million miles without maintenance, there's no guaranteed adoption curve, production capacity, distribution and logistic timeline, consumer acceptance, these are all hard unknown realities regardless of how silvery the bullets are.
- Robotbeat 5y ago
  It IS relevant right now. If the "lifecycle emissions" of near-term renewables is used to argue against deploying them and instead using existing carbon-emitting sources, then you've delayed progress and made things impossible to resolve except by basically shutting down everything (which would kill people and is politically infeasible). Decarbonization compounds. That means that "lifecycle emissions" analysis can end up being too pessimistic if you consider changes made in a vacuum. Electric cars require steel and electricity to make, so considered by themselves (while still definitely worth it) don't look as good as they do when you consider we will need to be decarbonizing steel and electricity as well. Power plants need vehicles and steel as well, so decarbonizing transport and steel also reduces the lifecycle emissions of power plants! I think people resist this type of thinking because of a different kind of magical thinking: a sort of anti-silver-bullet magic. They have the idea of fossil fuels as fundamental to civilization, like we can't actually get rid of them. But this isn't true. We can eliminate fossil fuel usage just fine. We should consider fossil fuel as the seed corn. Instead of feeling bad that it takes fossil fuels to do the initial manufacture of geothermal (or whatever), consider it as simply priming the pump, as seed corn. There is no better use for fossil fuels than assisting in manufacturing their total replacements.
DennisP 5y ago
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.
dalbasal 5y ago
Well put. Parent is correct that it "all counts," but that doesn't mean it all resolves to the same thing over the long term. For example, one of solar's key strength is the improvement curve that its on. Carbon, energy and dollar costs are improving. So in a sense, every Kw produced now reduces the costs of Kw produced in the future. Its valid an important to think of lifecycle costs currently, it's also not a full picture.
- ZeroGravitas 5y ago
  I believe most decent life cycle analyses these days will include a prediction of carbon intensity of electricity used in the future as one more thing to help compare costs/benefits now vs the future. As an example burning trash for power gets relatively worse as other energy sources become carbon free, while recycling gets relatively better as the energy required becomes lower carbon and/or cost.
  - dalbasal 5y ago
    Possibly, though there isn't really a standard way of doing so. I doubt that any such analysis accounts (nor should it) for technological curves yielded by investing in one technology or another. There are limits to any one calculation.

by emtel 5y ago

imtringued 5y ago

You can probably do "time" arbitrage here. The CO2 price is low today so CO2 intensive construction is still viable today but it won't be in the future. Thus your geothermal plant will end up becoming more profitable over time.

kristopolous 5y ago

> The life-cycle carbon cost of renewables isn't a fact about renewables. It's a fact about our current energy production mix, which renewables themselves will change over time. Sure but we are talking about right now. Things will eventually be swapped out. That's a different conversation though, it's an advocacy and not a descriptive one. People tend to use things that are marginally adequate way longer than anyone intended. For instance, the ancient Roman gravity dam of Proserpina is still doing its job. Even if we had say a sleek $1,000 self driving solar car that never needs charging and goes for a million miles without maintenance, there's no guaranteed adoption curve, production capacity, distribution and logistic timeline, consumer acceptance, these are all hard unknown realities regardless of how silvery the bullets are.

Robotbeat 5y ago
It IS relevant right now. If the "lifecycle emissions" of near-term renewables is used to argue against deploying them and instead using existing carbon-emitting sources, then you've delayed progress and made things impossible to resolve except by basically shutting down everything (which would kill people and is politically infeasible). Decarbonization compounds. That means that "lifecycle emissions" analysis can end up being too pessimistic if you consider changes made in a vacuum. Electric cars require steel and electricity to make, so considered by themselves (while still definitely worth it) don't look as good as they do when you consider we will need to be decarbonizing steel and electricity as well. Power plants need vehicles and steel as well, so decarbonizing transport and steel also reduces the lifecycle emissions of power plants! I think people resist this type of thinking because of a different kind of magical thinking: a sort of anti-silver-bullet magic. They have the idea of fossil fuels as fundamental to civilization, like we can't actually get rid of them. But this isn't true. We can eliminate fossil fuel usage just fine. We should consider fossil fuel as the seed corn. Instead of feeling bad that it takes fossil fuels to do the initial manufacture of geothermal (or whatever), consider it as simply priming the pump, as seed corn. There is no better use for fossil fuels than assisting in manufacturing their total replacements.

DennisP 5y ago

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.

dalbasal 5y ago

Well put. Parent is correct that it "all counts," but that doesn't mean it all resolves to the same thing over the long term. For example, one of solar's key strength is the improvement curve that its on. Carbon, energy and dollar costs are improving. So in a sense, every Kw produced now reduces the costs of Kw produced in the future. Its valid an important to think of lifecycle costs currently, it's also not a full picture.

ZeroGravitas 5y ago
I believe most decent life cycle analyses these days will include a prediction of carbon intensity of electricity used in the future as one more thing to help compare costs/benefits now vs the future. As an example burning trash for power gets relatively worse as other energy sources become carbon free, while recycling gets relatively better as the energy required becomes lower carbon and/or cost.
- dalbasal 5y ago
  Possibly, though there isn't really a standard way of doing so. I doubt that any such analysis accounts (nor should it) for technological curves yielded by investing in one technology or another. There are limits to any one calculation.