Pelton Water Turbines

Pelton water turbines are grouped in water turbine impulse. Pelton water turbine consists of a set of running blades that are rotated by jets of water which is sprayed from one or more device called as nozzle. Pelton water turbine is one of water turbine type that has highest efficiency. Pelton water turbine is suitable for high head.

Figure 1: Pelton Water Turbine
(Source: http://en.wikipedia.org/wiki/pelton_wheel)

Form of turbine blade consists of two symmetrical parts. Blade is formed so that the jets of water will hit the middle of blades and jets of water will be turned in both directions so that it can reverse the jets of water well and release the blade from side forces. For turbines with high power, water spray system is divided by multiple nozzles. Thus the diameter of water jet can be reduced and bucket blade will be smaller. Pelton water turbines for large-scale plant require approximately 150 meters head but for the micro-scale 20 meters head is adequate.

Figure 2: Pelton Water Turbine Blade

Figure 3: Pelton Water Turbine Nozzle
(Source: http://europa.eu.int/en/comm/dg17/hydro/layman2.pdf)