The kind of large-scale agriculture most often used today relies on a huge amount of hydrocarbons. As I mentioned above, the need for hydrocarbons would still be compounding -- the more biofuels grown, the more biofuels required to grow them -- unlike capturing and transporting electricity on the already-existing infrastructure.
I would love to see large-scale sustainable agriculture that doesn't require such a staggering amount of resources. There are many smart people working on this problem. Unfortunately I don't see those advances outpacing the advances being made in electricity storage and transport.
Theoretically, it seems to me that if the plants were efficient enough, one should be able to obtain the hydrocarbons from them there are needed during the process of agriculture.
I guess the really important point is your second paragraph: As long as there are advances in both the plants and the technology, the plants may simply be unable to catch up.
I would love to see large-scale sustainable agriculture that doesn't require such a staggering amount of resources. There are many smart people working on this problem. Unfortunately I don't see those advances outpacing the advances being made in electricity storage and transport.