The Kaplan turbine has variable pitch runner blades for a low head, high volume hydroelectric generating system.
The Kaplan turbine is a propeller-type water turbine that has adjustable [pitch] blades. Its invention allows efficient power production in low head applications. (That means the machine works effectively with low water pressure.) It is in wide use in hydroelectric generating plants around the world where lower pressure, high volume water sources are being tapped for energy generating applications.
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