Electricity powers the light, water supply systems provide water for washing, wastewater treatment plants treat the sewage, and natural gas or electricity heats the water. Some government establishments also provide electric, gas, water, and wastewater treatment services and employ a significant number of workers in similar jobs, but they are part of government and not included in this industry. [ Career Guide to Industries ]
The utilities sector is comprised of three distinctly different industries.
Electric power generation, transmission, and distribution. This segment includes firms engaged in the generation, transmission, and distribution of electric power. Electric plants harness highly pressurized steam, flowing water, or some force of nature to spin the blades of a turbine, which is attached to an electric generator. Coal is the dominant fuel used to generate steam in electric power plants, followed by nuclear power, natural gas, petroleum, and other energy sources. Hydroelectric generators are powered by the release of the tremendous pressure of water existing at the bottom of a dam or near a waterfall. Renewable sources of electric power—including geothermal, wind, and solar energy—are expanding rapidly, but only make up a small percentage of total generation.
Legislative changes and industry competition have created new classes of firms that generate and sell electricity. Some industrial plants have their own electricity-generating facilities, capable of producing more power than they require. Those that sell their excess power to utilities or to other industrial plants are called non-utility generators (NUGs). Independent power producers are a type of NUG that are electricity-generating plants designed to take advantage of both industry deregulation and the latest generating technology to compete directly with utilities for industrial and other wholesale customers.
Transmission lines supported by huge towers connect generating plants with industrial customers and substations. At substations, the electricity’s voltage is reduced and made available for household and small business use via distribution lines, which usually are carried by telephone poles.
Natural gas distribution. Natural gas, a clear odorless gas, is found underground, often near or associated with crude oil reserves. Exploration and extraction of natural gas is part of the oil and gas extraction industry, covered elsewhere in the Career Guide to Industries. Once found and brought to the surface, it is transported throughout the United States, Canada, and Mexico by gas transmission companies using pressurized pipelines. Local distribution companies take natural gas from the pipeline, depressurize it, add its odor, and operate the system that delivers the gas from transmission pipelines to industrial, residential, and commercial customers. Industrial customers, such as chemical and paper manufacturing firms, account for almost a third of natural gas consumption. Electric power plants, residential customers who use gas for heating and cooking, and commercial businesses—such as hospitals and restaurants—account for most of the remaining consumption.
Water, sewage, and other systems. Water utilities treat and distribute nearly 34 billion gallons per day to customers nationwide. Water is collected from various sources such as rivers, lakes, and wells. After collection, water is treated, and sold for residential, industrial, agricultural, commercial, and public use. Depending on the population served by the water system, the utility may be a small plant in a rural area that requires the occasional monitoring of a single operator or a huge system of reservoirs, dams, pipelines, and treatment plants requiring the coordinated efforts of hundreds of people. Sewage treatment facilities operate sewer systems or plants that collect, treat, and dispose of waste from homes and industries. Other utilities include steam and air-conditioning supply utilities, which produce and sell steam, heated air, and cooled air.
[ Excerpted from Bureau of Labor Statistics, U.S. Department of Labor, Career Guide to Industries, 2008-09 Edition - Utilities ]