The wiki says

True energon is, however, extremely rare: in most universal streams, the Transformers' long war has left Cybertron drained of all but the smallest fraction of the substance, and although it has been known to exist on a small sampling of other planets throughout the multiverse (usually Earth), its paucity leaves the Transformers usually subsisting on artificially-generated substitutes created from other local energy sources.

It seems like the best stuff is fossil Energon. It can be synthesized, but it doesn't say anything about renewable sources. The Autobots and Deceptocons would fight together against Captain Planet.

(I have much better things to be doing, but this is some quality procrastination)