Pelton Wheel at Kinlochleven

Kinlochleven was once the site of an aluminium smelter. This requires a lot of electrical energy which was generated by hydroelectricity. Thus the Pelton Wheel is a memorial to this former industry. The old smelter building is now the national ice climbing centre. Reading about the Pelton Wheel, I have learned that it is different from the wheels used in corn-grinding water mills where the water feeds in over the top of the wheel. There the water has no kinetic energy but its weight in the bucket pushes down on the wheel. Here the water undershoots the wheel. The wheel puts a force on the water to stop it moving so by Newton's Third Law the water puts an equal an opposite force on the wheel. Clever design means that if the water really does leave with no kinetic energy, the wheel's rim is moving at half the speed that the water had.