Around half of our CO2 emissions aren't from big power plants, or even small power plants, according to researchers from the University of Calgary. They're from diffuse sources, like car exhaust, home heating and airplanes, which can't be easily sucked up at the source. Led by climate scientist David Keith, the Calgary group is working on technology that could soak those "diffuse emissions" right out of the air.
Their system is a kind of air scrubbing tower, which takes air and reacts the CO2 out of it by exposing it, in this case, to sodium hydroxide. Then the stuff goes through a few chemical intermediaries eventually leaving separated CO2 that can be piped away, and more hydroxide to feed back into the scrubber.