Fuel Cans are multi-purpose storage units that can be used to supply power to a generator, generating EU as it burns. Depending on the type of fuel used will determine how long it can burn in a generator. When canned with Biofuel Cells, they burn roughly 6 times longer than a piece of coal. If Coalfuel Cells are used instead, it will burn 19 times longer than a single piece of coal. Fuel cans are also used in the crafting of Jetpacks. The downside to coal and fuels cells is the amount of resources that go into them, especially early on in the game.