A prevailing theme throughout the development of man has been the need for energy. Before the age of water power, people relied on self-generated power (i.e., arms and legs) or the strength of domesticated animals (horse, oxen, etc.) to produce energy. Early primary energy sources included wood and other kindling used to create heat and provide lighting. The Mesopotamians, Egyptians, Romans and Chinese were able to harness the potential of moving water to produce energy, starting as early as 200 B.C.
The Industrial Revolution of the 18th and 19th centuries created the need for more efficient sources of energy to power factories and machine tools. The dominant primary source of energy shifted from wood, and other kindling, to coal. James Watt’s steam engine, patented in 1781, was the driving force behind the increased production and efficiency of the Industrial Revolution. The Second Industrial Revolution (which took place during second half of the 19th century, until World War I) was driven by electricity. Thomas Edison patented the first system for the distribution of electricity in 1880.
Philadelphia created the first municipally owned natural gas distribution company in 1836 (Philadelphia Gas Works), but it was not until the end of the 19th century, however, that energy became widely offered to the public and other third parties. Initially, the only use of natural gas and electrical power was lighting, but the development of electric motors, communication technology, heating systems and other appliances created additional demand. The use of electrical appliances grew throughout the 20th century, creating a massive market for the use of electricity and natural gas.