Nature knows a thing or two. All you have to do is look. When a hydropower engineer and a medical scientist put their noggins together at the end of the 20th century, they came up with a new way to boost the power of existing hydroelectric stations by nearly 10 percent [source: Piesold and Caro]. All they did was apply the spiral-shaped design of human blood vessels to create a similarly shaped penstock pipe.
The helicoid penstock is similar to a rifle barrel, which has spiral grooves etched inside. Rushing water flows through the helicoid penstock, and like a bullet through a rifled barrel, begins to spin. The pipes focus the flow of the water directly on the electric turbine, improving the turbine's performance [source: Piesold and Caro].