Electricity

The Development of Electrical Applications

Electricity is defined as the flow of electrical power created through the conversion of a primary energy source. Although recorded knowledge of the phenomenon of electricity dates backs to ancient Greece, widespread scientific study and understanding did not begin until the mid-18th- and 19th-century work of Benjamin Franklin, Michael Faraday, Hippolyte Pixii, Nikola Tesla, and Thomas Edison. A lack of early applications as well as safety concerns further delayed the widespread social and commercial applications of electricity.

Several key developments increased both the feasibility and demand for electricity and electromagnetic energy by the late 19th century. Edison invented the electric light bulb and, later, the direct current (DC) electric motor and generator. Tesla developed the alternating current (AC) electric motor and generator, later selling his inventions to George Westinghouse. AC became the most widely used electrical power transmission system because of its ability to travel longer distances without excessive power loss, its lower expense, and its lighter motor weights. Electricity also powers pumps and electronic and computing devices.

Electric utility companies and infrastructure began to spread as demand for electricity increased, first in developed nations and later in the developing world. The availability of electrical power became widespread in the United States, Europe, and Japan by the mid-20th century, and most of the world had some level of electrical power access by the end of the 20th century. According to the CIA World Fact Book 2009 statistics, the top 10 nations and regions in international energy production are the United States, China, the European Union, Russia, Japan, India, Germany, Canada, France, and Brazil. Electrical power systems infrastructure has continued to expand in areas of the developing world where it is least available or reliable in the 21st century.

Modern electric utilities generate electricity and then transmit and distribute that power to their customers. Electric utilities use a variety of primary renewable and nonrenewable energy sources to produce electric power, including burning wood or coal, generating hydroelectric power through dams, geothermal energy, solar energy, and nuclear energy generated by nuclear power plants. Coal and hydroelectric power are the most common methods in commercial use. Grids of high-voltage wires transmit electrical energy to distribution centers, where it is then converted into the low-voltage, high-current electricity that is delivered to consumers (see Figure 1).

Key components of the electricity industry include infrastructure, markets, planning, and regulation. Utilities also study consumer demand fluctuations to determine times of peak use in a process called utility planning. Excess electrical energy can then be stored for later use. The widespread use of electricity and public safety issues surrounding the utility industry have led to the involvement of local and national governments and international organizations in industry regulation to ensure consistent affordable service and infrastructure safety.

...