we all know CO2 and H20 can be recombined to form fuels, its where the fossil fuels originally came from. Where do these bacteria get their energy from? Either from photosynthesis elsewhere, or by photosynthesis themselves. In either case, in order to offset the power plant at the rate is converting fuel to electricity, you need a huge area of plants or solar to recover _all_ CO2. But then you could just remove the fossil fuel burning power plant out of the equation.
It is still perpetuum mobile...