Energy - põhjalik referaat energiast
rotating the shaft connected to the generator. In a fossil-fueled steam turbine, the fuel is
burned in a furnace to heat water in a boiler to produce steam. Coal, petroleum (oil), and
natural gas are burned in large furnaces to heat water to make steam that in turn pushes on
the blades of a turbine.
Did you know that most electricity generated in the United State comes from burning coal?
In 2007, nearly half (48.5%) of the country's 4.1 trillion kilowatthours of electricity used
coal as its source of energy.
Natural gas, in addition to being burned to heat water for steam, can also be burned to
produce hot combustion gases that pass directly through a turbine, spinning the blades of
the turbine to generate electricity. Gas turbines are commonly used when electricity utility
usage is in high demand. In 2007, 21.6% of the nation's electricity was fueled by natural
gas.
Petroleum can also be used to make steam to turn a turbine
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