zlacker

> With the recent advances of turning CO2 into other substances, such as propane, should we be focusing more on closing the carbon cycle and simply be producing fossil fuels from the waste products of yesteryear?

That's much harder than it sounds, because (unlike, say, lithium) what's important in propane is the energy stored in it in the forms of chemical bonds, not the constituent elements. Basically, the resulting C/O/H we have is just waste product. We can't "just reassemble it back to propane" because to do it we need energy, and if we have that energy, why not just use it directly? No need to insert propane as an intermediary, barring unusual situations like jet fuel.

It's basically like trying to turn feces and urine back to a beef steak. Having carbon and hydrogen atoms isn't the hard part of producing beef.

>>yongji+(OP)
I'm not sure that's a fair comparison. We have plenty of energy, in the form of untapped solar and wind, for example. The challenge is storing and distributing it, for which energy dense hydrocarbons are very effective. (Even coal is more energy dense than lithium ion batteries, and that's nothing compare to oils and its distillates).

There was an interesting article discussed at length on HN recently about using electrolysis for synthesising propane, which along side the book The Material World has made me start questioning batteries as the storage solution of the future.