I wish they addressed the fact that methane that they will be producing is said to be an even more potent greenhouse gas than carbon dioxide. Are there any worries about the leakage for example?
This is an important point. Not for the "we'll build a gas station on mars"-scenario, but for the "we'll propose this as a climate solution".
Every way of replacing natural gas with some other source of methane - be it the sabatier process or biogas/biomethane - has this problem. It can only be a climate solution if you can bring leaks down close to zero, which is very challenging.
It also makes one wonder whether e-methane is really such a good idea or whether you'd rather look at other chemicals like ammonia or methanol.
Methane is produced naturally in vast quantities by decaying organic matter, cow farts, released from volcanoes, natural reservoirs, etc. I doubt that some small leaks in an industrial process would make a real difference. It would probably be undetectable in comparison to the leaks in our current natural gas infrastructure that we use for heating homes, cooking, and electrical generation.
This may very well be the case that it's a non-issue, but an article that only mentions the good parts without even acknowledging potential problems with the solution makes me think "what else did they not mention that a lay-person like me wouldn't know about?".
You have to put that in perspective bit. Methane is a powerful greenhouse gas but it breaks down in a few years as well. And then there is the notion that there is quite a lot of it leaking in the atmosphere already through natural processes, melting of the permafrost, and indeed as a side effect of oil/gas production. You'd have to produce stupendous amounts of fuel to have leakage to an extent that it actually matters.
So, if we'd actually capture and burned the gas, there would be little to worry about. Especially considering we'd be getting less of it out of the ground in fossil form.
Part of the article speaks about the uses that are a bit closer to home. I'm not that worried about Mars, that part is still SciFi to me and I probably won't live long enough to see it become reality. :-(
Essentially it would be almost infinitely easier to reverse all climate change on earth than to make another planet livable but it is in theory possible.
