Nice thing is that you can use energy to create methane and oxygen from water and CO2. It's the same process they intend to use on Mars for refuelling. Obvious

Nice thing is that you can use energy to create methane and oxygen from water and CO2. It's the same process they intend to use on Mars for refuelling. Obviously this is slower and more expensive on Earth than using natural methane, but if volume increases to the point that the fuel burn is an issue you could set this up with a renewable energy source. https://en.wikipedia.org/wiki/Sabatier_reaction https://en.wikipedia.org/wiki/Sabatier_reaction