A “Hydrokinetic” turbine is an integrated turbine generator to produce electricity in a free flow environment. It does not need a dam or diversion. Instream Energy Systems has coined the phrase Instream Energy Generation Technology or IEGT places turbines in rivers, manmade channels, tidal waters, or ocean currents. These turbines use the flow of water to turn them, thus generating electricity for the power grid on nearby land. In effect, IEGT is like planting windmills in the water and is environmentally friendly. While hydrokinetic includes generation from ocean tides, currents and waves, many researchers believe its most practical application in the near term is likely to be in rivers and streams.
Instream Energy Systems have the ability to deploy multiple turbines along a river, canal, or aqueduct in order to maximize their energy harvest with minimal impact on the existing canals. Two major benefits of hydrokinetic deployment are the reliability and the predictability of the water delivery systems. Unlike wind, the water deliveries are planned well in advance and therefore utilities can accurately predict when more power will be coming online. A 35 kilowatt hydrokinetic turbine has been installed in the Mississippi River near Hastings, Minnesota. Underwater tidal turbines are propelled by tidal currents. If the viable river and estuary turbine locations are made into hydroelectric power sites, researchers estimates that United States rivers and estuaries could provide up to 130,000 gigawatt-hours per year — about half the yearly production of the country’s dams.