(, Wed 28 Sep 2016, 5:58, Reply)
Or do you think rocket fuel magically rains down and is scooped up in buckets?
(, Wed 28 Sep 2016, 7:19, Reply)
If you can do that on mars with very limited resources compared to earth why not here for power production?
(, Wed 28 Sep 2016, 8:21, Reply)
The energy source on Mars is going to be solar panels (they covered that in the talk) or potentially if there's the will for it a nuclear source.
I'll leave you to figure out the source of the energy for the process on Earth.
(, Wed 28 Sep 2016, 10:22, Reply)