I have an Idea:
Turn off player lights. Add a lantern Item that they have to make with Bronze, iron, or steel. The better the metal, the less fuel consumption rate. The lantern could run off of wood chippings or coal. wood chips would have a luminosity of half the play light while coal would be the same as the player light. I was thinking 1 log = 15 chips and the (Iron) lantern burns at a rate of 3 chips per minute. coal burns at a rate of 1/4 ore a minute.
Just an idea...