A similar approach is being undertaken by researchers in Finland, but their focus is on producing a supplement for human food rather than stock feed.
"So instead of sugar we introduce carbon dioxide and hydrogen, and these the microbe uses for energy and carbon instead of sugars to grow. "We are about 10 times more environmentally friendly than plants and about 100 times better than animal-based proteins," he says.
This is part of how cities can operate in the future, like giant self sufficient spaceships but on & under the surface of the Earth. Powered by fusion reactors, recycling & refabricating everything, getting extra materials from seawater. Then most farmland can go back to nature.
This is a terrible idea. Will we use our precious drinking water to irrigate? Will we grow under lights in a sun-drenched country? Will we forsake our soil in favour of nutrient solution?