Oil is a resource used for smelting and running mining machines.
At the start of the game you have an oil income of 0 which you can increase by crafting the Oil Well.
When you use oil for smelting it is all consumed at once and if you have machinery running it is consumed per second.
|Items||Crafting Level||Crafting Materials||Effect|
|1||5||1 per second|
|23||25||5 per second|
|30||200||10 per second|
|43||500||20 per second|
Note that these effects do not add up cumulatively but instead each oil well overrides its predecessor. This means that you will gain just 10 per second with the Silver Well, instead of 16 per second (as it was the case in DH2).