There are many fossil autocrats, most countries are run by autocrats or on their way to become autocraties like hungary, turkey or the USA. The system of all those is very similar: The countries (or some companies for them) exploit fussil fuels and sell them; the profits are distributed by the autocrat to his own account, but also to his buddies and his propaganda system so they keep him in power. Excellent example how this works are Russia or Saud-Arabia.