Utilities in the United States were once commonly large regional monopolies; however, the growth of the renewable energy market has gradually caused a breakdown of the traditional model. The reduction in the price of renewables and energy storage, the establishment of carbon regulations, and the increase in distributed energy resources are further accelerating this change. Many utilities have begun to become more involved in the solar industry, with California based PG&E holding the largest solar power capacity of all such U.S. companies. Utilities are also looking into offering rooftop solar installations and providing consumers with community-shared solar options. In light of these emerging trends, traditional utilities have been heavily criticized for their aging infrastructure, and new distributed capacities are forcing companies to upgrade their transmission and distribution grids. As such, operating expenses for transmission and distribution of major investor-owned electric utilities have increased annually in the past few years and surpassed 16 billion U.S. dollars in 2018. Meanwhile, fossil steam and gas turbines remain the power plants with the highest operating costs.
As the traditional electric utility industry has been described as being in transition, several new supplier segments have begun to emerge. Network operators sell retail service providers access to their grid, while marketers sell energy futures and derivatives to businesses. In most areas across the United States, service providers and retailers that have bought power at competitive prices from the market can be selected directly by the consumers.
In 2018, Florida Power & Light Co was the leading retailer of electricity, having sold 59.11 terawatt hours of electricity to residential customers. It also held the largest residential client pool among electric utilities, closely followed by Southern California Edison Co.