A self-contained solar powered cargo-container-sized box that can create calories with minimal top-ups of material might make some marginal areas habitable.
This is the technology that's absolutely needed for off-Earth agriculture.
We take so many things for granted, like air and sunlight. I think the Biosphere 2 project was the only one that tried to figure out just what we need to support life in a closed system. It was horribly expensive and it looks to be horribly inefficient - 8 people to make the food and oxygen, and 3.14 acres of land. What we do currently for the space station is to ship them 1000 pounds of stuff every month per person.
We take so many things for granted, like air and sunlight. I think the Biosphere 2 project was the only one that tried to figure out just what we need to support life in a closed system. It was horribly expensive and it looks to be horribly inefficient - 8 people to make the food and oxygen, and 3.14 acres of land. What we do currently for the space station is to ship them 1000 pounds of stuff every month per person.