I have my doubts...
It is very hard to get an algae specie that can serve as both food for cattle and bio-fuel maker. Perhaps they are using genetic engineering? Or even worse the whole thing is a scam to take the hopeful coal industry for a ride, or even worse yet - they already know it isn't going to work, but have to scam the government to get an expansion to the plant. Governments aren't happy about supporting coal plant expansions in the US unless they are natural gas powered. This is not carbon neutral, but will at least stem the tide of carbon explosion in world wide energy needs.
I hope they are right, and I hope the feed stock at least equals what natural gas brings to the table, and reduces the emissions to near methane burning exhaust levels. The bio-fuel would at least slow the introduction of carbon into the atmosphere, and after all - it is better than no carbon filtration. I think they need to concentrate on a method and specie of algae that can grow explosively and efficiently and simply ship that back to the coal mine in the coal car train. The cars are empty all the way back to the mine, so this at least gives the load a useful mission. They could bury it in the mines for the next iteration of coal burning several thousand years from now - if in fact dry algae doesn't burn almost as good as coal to begin with?
Come to think of it dairy farms are already powering their operations with cow farts and poop methane, so even what carbon is not locked in the cow's (or our bodies for eating them), will serve another purpose in generation of power. Even putting algae underground may cause methane to build up in unused mines. They may have to build explosion proof robots to deposit the load in the abandoned mine; but vents can tap off the methane produced. As I said before - not carbon neutral but at least carbon complicated! HA!