I found this article: http://www.sciencedaily.com/releases/2008/09/080929123941.htm and it talks about a machine that absorbs CO2 invented by a professor from University of Calgary. I'm thinking to make a feasible model of it for construction (it's actually a school project), but the machine itself is quite new and I don't know how to relate that to physics. Do you think it's a good idea? What can I talk about from a physics point of view if I am to do that topic? Does anyone know how it works (from a physics point of view)?