HEADLINE
Wind Turbines
the bottom of the dam wall . A turbine propeller is turned by the force of the water . A shaft connects the propeller to a generator which converts the mechanical energy to electrical power .
The various methods employed in energy production in North America require the assimilation of a wide range of resources . At present , the vast majority of energy sources rely on a generator to convert various forms of energy into electricity . A generator produces electricity by moving wire or a disc , usually made of copper , between magnetic poles . The power distribution system requires large numbers of power cables , transformers and circuit breakers ; therefore , it too demands a substantial amount of resources . Each of these systems requires maintenance and periodic replacement of parts that must be calculated into the economic viability . The North American energy infrastructure encompasses an immense range of materials and technologies and will continue to expand in the coming years .
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