To decrease the amount of greenhouse emissions 10% below 1990 levels, Portland General Electric (PGE) in Oregon intends to replace coal plants with 2,362 MW wind energy systems and 557 MW of simple-cycle combustion turbines burning natural gas.
Riverbank Power has developed a project that is of high interest. Water gathered in a bungalow on a river shore will fall in a 600m deep gallery where turbines are mounted. The water pressure will rotate the huge turbines which will create electrical power.
The main idea is simple: find yourself a river, make sure its falling abruptly enough to have the necessary speed and velocity to spin your turbine, and make the necessary piping and flow control system.