Power Plant Workers

The first permanent, commercial electric power-generating plant and distribution network was set up in New York City in 1882 under the supervision of the inventor Thomas Edison. Initially, the purpose of the network was to supply electricity to Manhattan buildings equipped with incandescent light bulbs, which had been developed just a few years earlier by Edison. Despite early problems in transmitting power over distance, the demand for electricity grew rapidly. Plant after plant was built to supply communities with electricity, and by 1900 incandescent lighting was a well-established part of urban life. Other uses of electric power were developed as well, and by about 1910 electric power became common in factories, public transportation systems, businesses, and homes.

Many early power plants generated electricity by harnessing water, or hydro, power. In hydroelectric plants, which are often located at dams on rivers, giant turbines are turned by falling water, and that energy is converted into electricity. Until the 1930s, hydroelectric plants supplied most electric power because hydro plants were less expensive to operate than plants that relied on thermal energy released by burning fuels such as coal. Afterward various technological advances made power generation in thermal plants more economical. Burning fossil fuels (coal, oil, or gas) creates heat, which is used to make steam to turn turbines and generate power. During the last several decades, many plants that use nuclear reactors as heat sources for making steam have been in operation.

Today, energy from all these sources—hydropower, burning fossil fuels, and nuclear reactors—is used to generate electricity. Large electric utility systems may generate power from different sources at multiple sites. Although the essentials of generating, distributing, and utilizing electricity have been known for more than a century, the techniques and the equipment have changed. Over the years the equipment used in power generation and distribution has become much more sophisticated, efficient, and centralized, and the use of electric power exceeds the demand for workers.