Adds very large pipes with enormous throughput capabilities.
Mods introducing new content into the game.
Augmented or new ways of transporting materials - belts, inserters, pipes!
Things related to oil and other fluids.
Does underground duct have UPS advantage comparing to overground items?
As with the vanilla game - the smaller the number of entities, the less load on the system. If you mean it. Also, when using underground pipes, it is possible to increase the efficiency of fluid transfer.
