Quote Originally Posted by KC2UGV View Post
It is, most likely. However, the energy input to make and refine petrol is also greater than the output energy. And, the benefits of petrol isn't the input vs. output amounts, it's the energy density.
Well yeah, there is a lot of potential energy in a given volume of petrol. But any system than converts one form of energy to another is going to be at max efficiency "in=out" and more likely "in>out". "in < out" of course would require violating the fundamental laws on nature which as present is impossible. The idea of making fuel out of carbon scrubbed from the atmosphere is nice but not practical if we need to burn fossil fuel to make "fossil fuel" particularly if the system operates at a net loss overall. If it breaks even we are still not gaining much ground. Now if it can be designed to run efficiently off nuclear or renewable (solar, wind, etc) then it may be worthwhile to play around with, even just for sake of cleaning some of the crap out of the air.But as it stands at present this is not going to knock the oil companies out of business.