Electric mining drills required to saturate a belt
Given a resource patch of a certain type and a specified level of mining productivity research, how many electric mining drills are required to saturate the entire belt?
The first number is the calculated number for the entire belt, but is likely a fraction and not practical. The second number is divided by two and rounded up, giving an integer number of drills to put on each side.
Belts for a given number of drills on an ore patch
When cramming as many drills as possible into an ore patch, some of the belt lines might not have enough drills to compress the belt. Perhaps you have five belts coming from the ore patch, but only enough ore to saturate two belts. It helps to know exactly how many belts can be compressed to avoid building extra lines of belts and furnaces for maximum efficiency. This is crucial in the early game when resources are scarce, because you are in the process of setting up your production lines. In the previous example, it would make sense to use a 5-to-2 belt balancer (reducer) to shrink the number of belts, saving resources.
This calculator is a sort-of inverse of the one above that tells you how many drills you need. This one takes the number of drills on each side of the belt, and tells you how many belts’ worth of ore it will produce for each lane (left and right). If the two lanes are more than a little bit uneven, it may be worth redirecting some ore output onto the opposite lane.
Mining productivity breakpoints for electric mining drills on belts
When researching mining productivity, not every level of research will affect the number of drills needed to compress a belt of ore. Just in case you are contemplating starting that next level of research before bed but are not sure if it will have a meaningful impact on the number of drills per belt, this calculator will tell you the breakpoints.
Please note that this calculator determines the number of drills per side of the belt, since that is the practical application. If it takes 27 drills to saturate a belt, few people will bother concocting a way to have that odd-drill-out alternate belt lanes.