I think, generally, making CO2 is pretty easy. There are billions of things that make it as a byproduct and that's why we have a problem with runaway CO2. Thin

I think, generally, making CO2 is pretty easy. There are billions of things that make it as a byproduct and that's why we have a problem with runaway CO2. Things that consume CO2 are less common. But that is a good thing to think about. We don't know what industry will be like 200 years from now. I guess boring deep into the earth for methane and other gases to burn would be one way. No matter what happens, resources on this earth are limited, though.