A plentiful head of water can be made to generate directly without moving parts. In these designs, a falling column of water is deliberately mixed with air bubbles generated through turbulence or a pressure reducer at the high-level intake. This allows it to fall down a shaft into a subterranean, high-roofed chamber where the now-compressed air separates.
[pdf] A dwarf planet is a small that is in direct orbit around the , enough to be , but insufficient to achieve like the eight classical of the . The prototypical dwarf planet is , which for decades was regarded as a planet before the "dwarf" concept was adopted in 2006.
[pdf]