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In general, I think we should reserve the term "greenwashing" for fake projects. Lots of carbon offsets, for example, actually do nothing at all. If you're usin

In general, I think we should reserve the term "greenwashing" for fake projects. Lots of carbon offsets, for example, actually do nothing at all. If you're using those projects to offset your personal emissions, you're wasting your money. If you're a corporation, it's great because although it's not real, it's cheap and looks good. On the other hand, if you pay Climeworks then they will actually remove the CO2 from the air that you think they're removing, and bury it in deep basalt where it will turn into limestone. It will be quite expensive, and it's a woefully inadequate approach on its own, but it's real and measurable. For most corporations, it's worthless for greenwashing because it costs too much. (An oil company using captured CO2 to pump more oil out of the ground probably still counts as greenwashing, though.)

denton-scratch 3y ago
> bury it in deep basalt where it will turn into limestone CO2 + Basalt !== Limestone Limestone is the fossilized remains of sea creatures. Wikipedia says: "Calcium released by basalts binds CO2 from the atmosphere forming CaCO3 acting thus as a CO2 trap." https://en.wikipedia.org/wiki/Basalt#Geochemistry https://en.wikipedia.org/wiki/Basalt#Geochemistry CaCO3 is indeed the principal component of limestone, but not all Calcium Carbonate is limestone. I have no idea whether the process of basalt binding CO2 is efficient; WP doesn't detail the process. Nor does TFA; and I'm not surprised, because Oxy's goals are completely orthogonal to the production of CaCO3.
tsimionescu 3y ago
The majority of these projects are net carbon emitters, so they fit any definition of greenwashing. I also consider woefully small and unscalable, even if real, contributions to represent greenwashing. For example, the plastic straws craze, that attacked a problem that barely even constitutes a fraction of a fraction of a percent of plastic pollution, was pure greenwashing. And by this definition, literally all carbon capture initiatives, even the most well intentioned, are just greenwashing.
- DennisP 3y ago
  They're only net carbon emitters if they're powered by fossil fuels. The Climeworks plant is powered by geothermal. Any renewable or nuclear power source would be fine. It's expensive but it's scalable. There is a vast supply of suitable basalt formations. In terms of land area, it absorbs a thousand times as much CO2 as planting trees. I have seen a lot of complaints about the sheer number of devices that would be required, but this is the sort of scale that civilization is accustomed to. We built enough hardware to put that CO2 in the air. We can build enough to take it out. The real question is whether it can be made cheap enough in mass production to make a difference. That will partly depend on clean energy costs, but they are dropping constantly. It's certain that reducing emissions will be more cost-effective in most cases, but for some applications, like long-distance jet travel, we probably can't get away from hydrocarbon fuels for the foreseeable future.
  - tsimionescu 3y ago
    From what I'm reading, the method they're using right now to store the CO2 requires around 25 tonnes of water per tonne of captured CO2, and requires clean water at that. They are apparently working on using saltwater instead, but don't have the tech yet. So I'm not personally convinced it is actually scalable for now. I will admit that they seem more serious than others (in particular, more than the company in this article, which is using CO2 to push more oil out of the ground).

denton-scratch 3y ago

> bury it in deep basalt where it will turn into limestone CO2 + Basalt !== Limestone Limestone is the fossilized remains of sea creatures. Wikipedia says: "Calcium released by basalts binds CO2 from the atmosphere forming CaCO3 acting thus as a CO2 trap." https://en.wikipedia.org/wiki/Basalt#Geochemistry https://en.wikipedia.org/wiki/Basalt#Geochemistry CaCO3 is indeed the principal component of limestone, but not all Calcium Carbonate is limestone. I have no idea whether the process of basalt binding CO2 is efficient; WP doesn't detail the process. Nor does TFA; and I'm not surprised, because Oxy's goals are completely orthogonal to the production of CaCO3.

tsimionescu 3y ago

The majority of these projects are net carbon emitters, so they fit any definition of greenwashing. I also consider woefully small and unscalable, even if real, contributions to represent greenwashing. For example, the plastic straws craze, that attacked a problem that barely even constitutes a fraction of a fraction of a percent of plastic pollution, was pure greenwashing. And by this definition, literally all carbon capture initiatives, even the most well intentioned, are just greenwashing.

DennisP 3y ago
They're only net carbon emitters if they're powered by fossil fuels. The Climeworks plant is powered by geothermal. Any renewable or nuclear power source would be fine. It's expensive but it's scalable. There is a vast supply of suitable basalt formations. In terms of land area, it absorbs a thousand times as much CO2 as planting trees. I have seen a lot of complaints about the sheer number of devices that would be required, but this is the sort of scale that civilization is accustomed to. We built enough hardware to put that CO2 in the air. We can build enough to take it out. The real question is whether it can be made cheap enough in mass production to make a difference. That will partly depend on clean energy costs, but they are dropping constantly. It's certain that reducing emissions will be more cost-effective in most cases, but for some applications, like long-distance jet travel, we probably can't get away from hydrocarbon fuels for the foreseeable future.
- tsimionescu 3y ago
  From what I'm reading, the method they're using right now to store the CO2 requires around 25 tonnes of water per tonne of captured CO2, and requires clean water at that. They are apparently working on using saltwater instead, but don't have the tech yet. So I'm not personally convinced it is actually scalable for now. I will admit that they seem more serious than others (in particular, more than the company in this article, which is using CO2 to push more oil out of the ground).