> The main energy cost is in getting the CO2 to release from the absorbent — to desorb. And that’s when things get really expensive, because this requires a lot of energy...we don’t make or need pure CO2 gas, so we don’t need to desorb it. Therefore, we avoid the vast majority of this cost. Instead, we capture CO2 in water and then use it in water to make fuel. ARPA-E refers to this as “reactive CO2 capture” and identifies it as a significantly lower-cost DAC approach.
How good is water at capturing CO2 compared to the other absorbents? My guess, not as good. So is more CO2 released because they're capturing with water?
They are capturing with hydroxide salt dissolved in water. At issue in all such scenarios is how you get the CO2 back out. They claim to have something uniquely clever for that. It will soon be evident how well it works.
> The main energy cost is in getting the CO2 to release from the absorbent — to desorb. And that’s when things get really expensive, because this requires a lot of energy...we don’t make or need pure CO2 gas, so we don’t need to desorb it. Therefore, we avoid the vast majority of this cost. Instead, we capture CO2 in water and then use it in water to make fuel. ARPA-E refers to this as “reactive CO2 capture” and identifies it as a significantly lower-cost DAC approach.