Utility company

A public utility (usually just utility) is an organization that maintains the infrastructure for a public service (often also providing a service using that infrastructure). Public utilities are subject to forms of public control and regulation ranging from local community-based groups to statewide government monopolies.

The term utilities can also refer to the set of services provided by these organizations consumed by the public: electricity, natural gas, water, and sewage. Broadband internet services (both fixed-line and mobile) are increasingly being included within the definition.

In the United States, public utilities are often natural monopolies because the infrastructure required to produce and deliver a product such as electricity or water is very expensive to build and maintain. As a result, they are often government monopolies, or if privately owned, the sectors are specially regulated by a public utilities commission. The first public utility in the United States was a grist mill on Mother Brook in Dedham, Massachusetts.

Developments in technology have eroded some of the natural monopoly aspects of traditional public utilities. For instance, electricity generation, electricity retailing, telecommunication, some types of public transit and postal services have become competitive in some countries and the trend towards liberalization, deregulation and privatization of public utilities is growing, but the network infrastructure used to distribute most utility products and services has remained largely monopolistic.

...
Wikipedia