I am at a point in the game where I want to construct a moonbase to begin harvesting unobtanium. However, I need 40k oil, where my max is only 20k right now. For other resources the max is increased by warehouses, harbors (and tradeships) and barns. For oil, it seems like Oil Wells are the only way to increase the oil cap. It feels unnatural, because I have more then enough oil to keep my magneto's and calciners running.
Is it true that the only way increase the oil cap is by building more oil wells, and will there be later (in-game later, not begin developed) another way the cap, for example by a workshop upgrade?