Just as high-tech windmills tap the power of wind to generate electricity, a new water-mill technology promises to efficiently tap the flow of water in rivers, streams, and tidal basins. It could be a new source of clean, renewable, and unobtrusive energy.
The quest for clean, renewable energy has resulted in a number of interesting technologies. One of the newest is now being tested; it's called Instream Energy Generation Technology or free flow hydro power. It’s a technology that promises to tap energy wherever there is a river, stream, canal, or any place where water flows.
What is Instream Energy Generation Technology?
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.
Types of Turbines
There are several types of turbines available, depending on the characteristic of the water site and other needs. The axial flow rotor turbine consists of a concentric hub with radial blades, resembling a wind mill. Either a built in electrical generator or a hydraulic pump which turns an electrical generator on land provides the electricity.
The open center fan turbine consists of two donut shape turbines which rotate in the opposite direction of the current. This in turn runs a hydraulic pump that in turn drives a standard electrical generator.
A helical turbine resembles a strange sculpture with hydrofoil sections that keep the turbine oriented to the flow of the water. The leader edge of the blades turns in the direction of the water.
The cycloidic turbine resembles a paddle wheel, where the flow of the water turns the wheel with lift and drag being optimized.
Lift or Flutter Vanes looks like a huge Venetian blind. Hydroplane blades are caused to oscillate by the flowing water, thus generating electricity.