The green-house gas company

I have a proposal for a new company. It will be located in Sahara where a huge green-house will be built. The volume shall consist of a long glass tunnel which is gas-tight to the surrounding. In the tunnel, a new plant will be grown. This plant will be gene modified to operate in a very high CO2 atmosphere of, say, 20%. It will also be designed to be super efficient in converting CO2 to useful compounds, e.g. some natural gas or wood that can be use in construction. The third design criterion is that the plant should use salty water for its sustained operation. Hence, water can be extracted from the Mediterranean see. CO2 will be distributed in pipes from the whole of Europe and since it is costly for industry to produce CO2, we will charge for taking their CO2.