Vertical Axis Hydro Turbine
BEC is using a new design with insights applied to an old concept that was patented but never built by French hydro engineer Darrieus over 50 years ago. Extensive model testing and field trials have evolved into a new type of low head water turbine whose genesis was the vertical axis catenary type wind turbine proposed by Darrieus, 1931.
The genesis of the vertical axis turbine has an eighty year history. Through extensive model testing and several field trials with vertical axis turbines, the design for a new low head water turbine emerged. The Blue Energy turbine is a vertical axis hydro turbine that generates electricity from the kinetic movement of water in rivers and tidal currents. Four fixed hydrofoil blades of the turbine are connected to a shaft that drives a generator.
The vertical hydrofoil blades employ a hydrodynamic lift principle that causes the turbine foils to move proportionately faster than the speed of the surrounding water. The cross-flow design is unidirectional, making power on both the ebb and the flow of the tide. The turbine is designed to work through the entire tidal range, beginning to generate electricity at a water velocity of 1 meter per second.
This rotor is mounted in a marine caisson which directs the water flow through the turbine, houses the rotor, and supports the generator and electronic controls in a dry climate controlled machinery room above the water line.
The vertical axis hydro turbine may be employed at any scale ranging from floating micro turbines that are one or two kilowatts to massive gravity mounted tidal turbines that will form tidal bridges when fully scaled.