It depends - how realistic are you trying to be? For most groups, the 9 day limit is less of a resource-management challenge and more of an occasional adventure hook ("We've been running from the raiders for a week, and we're almost out of coal! What now?"). That keeps the focus on the PCs and the things they do, and off of the mechanics of how a mech operates, which is good because if we get too scientific the whole thing could fall to pieces on us.dulsi wrote:Another question: A mech's fuel bins store 9 days worth of coal. Is that 9 days of 24 hour activity? Or 9 days of 8 hour activity? I assume it is the first so a mech could operator for 27 days assume it was only on for 8 hours a day.
But serious questions deserve answers. A steam-driven mech is "active" to some degree around the clock. It will burn more fuel when it needs more power, like when it's traveling or fighting, but it will always be burning some coal to keep its pressure up in case it needs to take action on short notice. It takes a while to heat enough water for a full head of steam. A mech that's only burning coal for 1/3 the usual time will probably have even less than 1/3 of the usual operating hours - it will have to warm up every day. Make sense?