Splitting water for fuel while removing CO₂ from the air

In electrolysis, a device powered by electricity is used to split H2O, producing hydrogen gas. Several chemical modifications to this process have been proposed that can also grab CO2 from the atmosphere. Like the idea of using biofuels, this represents a "win-win" by producing an energy resource while capturing CO2, bringing the cost down.

Obviously, this scheme has its drawbacks. Quarrying rock has its own localized environmental impact, as could pumping all that extra bicarbonate into the ocean. But the researches argue that the idea is worth studying much more closely. The more options for removing atmospheric CO2 we work up, the more likely it is that one catches on when serious incentives finally arrive.