alt Hacker NewsTesla is the free cashflow play that is probably the most important for mars as there is no distilled fermented dinosaur juice on mars, but considerably more by ratio of lithium / oil than the Earth. Our flintstone fire mobiles won’t work so well there, and battery / solar will be important there for everything, including mobility and armies of slave robots.
Mars gets less sunlight on a good day for solar power; the inverse cube law really hits you harder than you'd think. And that's before accounting for the planet wide dust storms that can last for months.
We're probably looking at nuclear fission generators to get started, then converting to geothermal at any appreciable (and maybe fusion, inshallah).