4 ms·

"According to Nilsen's calculations, the cost of implementing enhanced weathering is about $20/T-CO2. If there are two teratons of excess CO2 in our atmosphere,

by giarc 3y ago

"According to Nilsen's calculations, the cost of implementing enhanced weathering is about $20/T-CO2. If there are two teratons of excess CO2 in our atmosphere, enhanced weathering can remove one teraton for about $400 billion US per year, over the next forty years." I wonder what $400 billion/year in just solar panel purchasing and install would do to the climate? $400 billion/year could build a lot of nuclear plants as well. Begs the question, if we had unlimited money, what would we do that would be potential solve the climate crisis?

PaulHoule 3y ago
Enhanced weathering has the advantage that, if it works, it really takes CO2 out of the atmosphere and also reverses ocean acidification. It's hard to know if it really works though because it is spread over such a large area and is hard to measure. Contrast that to injection into a saline aquifier where you can put a meter on the pipeline and know exactly how much gas you injected. One basic challenge with it is that you have to more-or-less pulverize the rock to make it chemically reactive and you have to do that without generating more CO2 or spending too much money. This looks like the most attractive scheme yet and it's got the plus of raising crop yields. https://www.theguardian.com/environment/2023/may/30/rock-flour-greenland-capture-significant-co2-study https://www.theguardian.com/environment/2023/may/30/rock-flo...
- wolfram74 3y ago
  We have satellites that can track CO2 concentrations in the air[0], allegedly at high resolution. If you spread out weathering rock to, I dunno, a square a few kilometers to a side, a gradient in CO2 might be measurable? If you're objective is much more quantitative than that, it probably is a non starter. Unless you were maybe flowing air actively over a controlled system and could take measurements at the input and output grating. But that seems a bit much. [0]https://www.esa.int/Applications/Observing_the_Earth/Copernicus/Carbon_dioxide_monitoring_satellite_given_the_shakes https://www.esa.int/Applications/Observing_the_Earth/Coperni...
  - PaulHoule 3y ago
    If you did it at a large enough scale it would be detectable. It is not entirely undestood, but when Mt. Pinatubo blew up atmospheric CO2 levels dropped: https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2004GL019760 https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/200...
mattashii 3y ago
Enhanced weathering's goal is to remove CO2 from the atmosphere, not to create energy. Nuclear/solar/wind doesn't capture already-emitted CO2 from the atmosphere, and direct carbon capture and storage (DCCS) methods currently cost much more than the 20$/T-CO2. While adopting solar/wind/nuclear is important, the current level of CO2 in the atmosphere is already too high, so we need to apply some DCCS to return to 'normal' levels of CO2 in the atmosphere, and enhanced weathering sounds like a promising technology we could use to achieve that.
hgomersall 3y ago
If we had unlimited money (which most monetarily sovereign governments do by the way) we'd be limited by real resources - the materials, the manufacturing capacity, the people that do the work. Long term strategic thinking is needed to direct what resources we have to where they are most needed for the long term goal.
bryanlarsen 3y ago
In net terms, even at today's interest rates, solar panels have a negative net cost. In other words, if you borrow $1 to install panels and then use the cost savings to pay back the loan, your loan will be paid off within 3 - 20 years and then keep reducing your electricity costs. So solar panels are cheaper than geoengineering. Similarly, so is wind, short term storage, a small amount of overbuild of renewable generation, increased interconnect, EV's, et cetera. IOW, we would save money on net for the first >80% of carbon emission elimination. Only for the last few percent of emissions is it worth discussing using solutions that cost money rather than save money. Things like cement production, long haul flights, et cetera.
- Scarblac 3y ago
  A problem of solar panels and other types of green energy is that by themselves they don't reduce CO2 emissions: we use the green energy on top of the energy from fossil fuels. Even with all the green energy installed world wide so far, global CO2 emissions are still increasing.

by giarc 3y ago

PaulHoule 3y ago

Enhanced weathering has the advantage that, if it works, it really takes CO2 out of the atmosphere and also reverses ocean acidification. It's hard to know if it really works though because it is spread over such a large area and is hard to measure. Contrast that to injection into a saline aquifier where you can put a meter on the pipeline and know exactly how much gas you injected. One basic challenge with it is that you have to more-or-less pulverize the rock to make it chemically reactive and you have to do that without generating more CO2 or spending too much money. This looks like the most attractive scheme yet and it's got the plus of raising crop yields. https://www.theguardian.com/environment/2023/may/30/rock-flour-greenland-capture-significant-co2-study https://www.theguardian.com/environment/2023/may/30/rock-flo...

wolfram74 3y ago
We have satellites that can track CO2 concentrations in the air[0], allegedly at high resolution. If you spread out weathering rock to, I dunno, a square a few kilometers to a side, a gradient in CO2 might be measurable? If you're objective is much more quantitative than that, it probably is a non starter. Unless you were maybe flowing air actively over a controlled system and could take measurements at the input and output grating. But that seems a bit much. [0]https://www.esa.int/Applications/Observing_the_Earth/Copernicus/Carbon_dioxide_monitoring_satellite_given_the_shakes https://www.esa.int/Applications/Observing_the_Earth/Coperni...
- PaulHoule 3y ago
  If you did it at a large enough scale it would be detectable. It is not entirely undestood, but when Mt. Pinatubo blew up atmospheric CO2 levels dropped: https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2004GL019760 https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/200...

mattashii 3y ago

Enhanced weathering's goal is to remove CO2 from the atmosphere, not to create energy. Nuclear/solar/wind doesn't capture already-emitted CO2 from the atmosphere, and direct carbon capture and storage (DCCS) methods currently cost much more than the 20$/T-CO2. While adopting solar/wind/nuclear is important, the current level of CO2 in the atmosphere is already too high, so we need to apply some DCCS to return to 'normal' levels of CO2 in the atmosphere, and enhanced weathering sounds like a promising technology we could use to achieve that.

hgomersall 3y ago

If we had unlimited money (which most monetarily sovereign governments do by the way) we'd be limited by real resources - the materials, the manufacturing capacity, the people that do the work. Long term strategic thinking is needed to direct what resources we have to where they are most needed for the long term goal.

bryanlarsen 3y ago

In net terms, even at today's interest rates, solar panels have a negative net cost. In other words, if you borrow $1 to install panels and then use the cost savings to pay back the loan, your loan will be paid off within 3 - 20 years and then keep reducing your electricity costs. So solar panels are cheaper than geoengineering. Similarly, so is wind, short term storage, a small amount of overbuild of renewable generation, increased interconnect, EV's, et cetera. IOW, we would save money on net for the first >80% of carbon emission elimination. Only for the last few percent of emissions is it worth discussing using solutions that cost money rather than save money. Things like cement production, long haul flights, et cetera.

Scarblac 3y ago
A problem of solar panels and other types of green energy is that by themselves they don't reduce CO2 emissions: we use the green energy on top of the energy from fossil fuels. Even with all the green energy installed world wide so far, global CO2 emissions are still increasing.