Use gravity in process design as much as you can. Gravity does not fail and any system that depends on its unfaltering consistency will be inherently stable and resilient. When you can harness height, either by creating it or utilizing any that already exists, you are leveraging potential energy that gets converted into kinetic energy. This is particularly potent and productive when used with water or liquid that can be used to generate force and pressure.
Think things like: gravity-fed systems used to create pressure for hoses, spigots or sinks. Or, refilling water reservoirs by pulling water downhill or down into catchment basins. Gravity-driven water can also be used to power small-scale mills and turbines to produce energy for homesteading needs.
Gravity-designed systems reduce dependence on sourced energy inputs, technological crutches, and labor expenditure in getting work performed and needs satisfied.