Originally posted by humy
electrolysis requires electricity and thus you would not create any more useful chemical energy than you would use up in the form of electrical energy! and then, if you put that chemical energy into a fuel cell, you would just convert that chemical energy BACK into electrical energy which is what you had in the first place! So I fail to see the point of that! A ...[text shortened]... ke sugar and food although you could use plants for that and without the need for hydrogen gas.
There are chemicals that store H2 and O2 in hydrides, very safe and the idea for all that is for portability. For transport, cars, trucks, whatever scheme comes about on Mars. It would be just like home and electric cars, except power would come from PV cells, but electricity would be sent out to homes with H2 and O2 generators. If PV cells were cheap enough, they could perhaps power cars directly, since a 1000 Kg car would only weigh 380 Kg and so forth, but of course it would still take the same energy to accelerate since it would still have the inertia associated with 1000 Kg. The problem there is Mars gets less energy from the sun than Earth does so there would have to be either extremely efficient cells or more of them.
Eventually fusion will be solved, maybe in 20 or 30 more years and all that will be in the past. One thing for sure. They will never burn fossil fuels there! Since there is not enough O2, that particular source of energy is going to be strictly Earthbound. So solar to start with, less energy available from the sun or not, will have to be the energy of choice, what happens next is up in the air, may the best system win.