Damming a river to generate electricity is so 20th century. Dams not only alter the landscape, but they can also affect wildlife (remember those fish ladders we mentioned?). What if we could harness the power of the river without building dams and reservoirs? A California-based company called Bourne Energy believes it has found the answer [source: Bourne Energy].
The company's RiverStar system harvests kinetic energy all along a river rather than in one spot, as dams do. Here's how it works: Engineers place a number of "modules" across a river. Each module is made up of a turbine, a stabilizer, a mooring system and an energy conversion system. High-tension steel cables hold each unit in place and connect one to another in an array. Flowing water passes through the turbines, and as they spin, they collect the river's energy, which drives a generator. Bourne officials say RiverStar can generate 50 kilowatts in a river with a water speed of 4 knots. The company adds that RiverStar does not affect the migration patterns of fish or impede river traffic.