Hydroelectricity

Hydroelectricity is the term referring to electricity generated by hydropower; the production of electrical power through the use of the gravitational force of falling or flowing water. It is themost widely used form of renewable energy
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Most machines that make electricity need some form of mechanical energy to get things started. Mechanical energy spins the generator to make theelectricity. In the case of hydroelectricity, the mechanical energy comes from large volumes of falling water. For more than 100 years, the simplest way to produce the volumes of falling water neededto make electricity has been to build a dam. However, large dams and reservoirs are not always appropriate, especially in the more ecologically sensitive areas of the planet.
For making smallamounts of electricity without building a dam, the small-scale hydroelectric generator is often the best solution, especially where fast-flowing streams on steep slopes are close by. A small-scalehydro system usually consists of an enclosed water wheel or turbine, which is made to spin by jets of high velocity water. The water is taken from the stream and moved down slope to the turbinethrough a long pipe called a penstock. Water flowing through the penstock picks up speed, and is directed at the blades of the turbine by nozzles. The turbine spins continuously, as long as there iswater to drive it. The turbine is connected to an electrical generator, and the electricity is then available for running appliances or charging batteries. The spent water is returned to thestream. This kind of system is called a “micro-hydro” system.
In this activity, we used plastic spoons to build a model of a simple micro-hydro system. It generates surprising amounts of electricity,provided we have a supply of pressurized water, such as from a lab sink. This model closely resembles real micro-hydro designs, and can produce enough electricity to light a small light bulb.