• In the 1970's and 80's hydroelectric and nuclear resources began to become more important. By the year 2000, we had moved away from absolute predominance of one particular resource to a complex mix of fossil fuels, hydroelectric and nuclear resources although fossil fuels still far exceeded any other source.



• energy sources used in residential and commercial applications has changed dramatically since World War II.

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• Until 1951 coal was still the predominant fuel. Petroleum and natural gas replaced coal in the late 1950s. Petroleum use began to decline in the mid-1970s. Electricity which was a token resource in 1950 has steadily increaseding percentage due to a rising popularity for heating and the increasing number of electrical appliances that are commonplace today.



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​• Wood was the predominant energy resource used in the U.S. until being replaced by coal in about 1885.

• As railroads moved west away from the east coast and its abundant forests, they could no longer rely on wood to fuel their steam locomotives.

• Coal became the fuel of choice because it possessed higher energy content than wood and significant deposits could be found along the paths of the rail lines.  Coal proved an economical source of the coke need to produce the iron and steel. During the last half of the 19th Century the energy consumption for transportation and industry grew in a concerted fashion fueled by coal. Coal remained king until after World War II when petroleum supplanted it.

• However, coal fired electrical generation allowed coal to remain an important energy resource.The emergence of petroleum and natural gas as predominant sources of energy. 



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As years go by not only does technology change but so does energy and the way we as people use it.