The history of the North American power grid, which is composed of five major grids

Tesla's alternating current power's most of the world's electric grids

In 1879, Thomas Edison’s light bulb relied on direct current, but such currents can't efficiently transmit power over long distances. Nikola Tesla introduced alternating current, which feature far fewer energy loses. Despite Edison’s attempts to discredit AC, Tesla proved its efficiency by lighting the 1893 Chicago World’s Fair.

Discover why Texas runs its own electric grid, separate from the other US interconnections

In 1935, electrical utilities in the Lone Star State opted to rely on the state's own fossil fuel reserves to power an independent electric grid. While this prevented the federal oversight required for the Eastern and Western Interconnections that span multiple states, it also meant Texas's grid was unable to draw sufficient backup power during the winter 2021 power grid failure.

The engineering underlying the electric grid and why it needs to be modernized

The system includes generators for producing electricity and millions of miles of transmission and distribution lines to transport the energy. The substantial increase in the number of electronic devices and electrical demand since the construction of much of the grid in the mid-1900s has strained infrastructure, requiring continuous upgrades and massive investments in new construction.

Niagara power helped electrify early New York City

Tesla's AC system at Niagara Falls was so successful that electricity generated there lit up Broadway theaters and powered NYC's subway system in the early 1900s.

Discover the catastrophic consequences of a failure of the US electrical grid—something that is more likely than many Americans think.

Discover what would happen in the US if the electric grid permanently went down

While the grid is designed with redundancies and to restart quickly in the event of an interruption, a long-term, widespread blackout would cut off most telecommunications, water, and sewage systems and cause supermarkets, which keep only about three days of inventory, to quickly empty. Without electricity and the transportation systems that rely on it, modern food production would also halt.

View a map of the balancing authorities managing electric systems and costs throughout the continental US

These are made up of utilities, Power Marketing Administrations—hydropower marketers from the Department of Energy—and groups of utilities that have formed regional entities called Regional Transmission Organizations or Independent System Operators. Collectively, balancing authorities ensure supply meets demand and can direct utilities to implement rolling blackouts to prevent permanent damage to electrical equipment.

Electrical grids worldwide must double their power delivery capacity by 2050 to meet surging demand from AI and electric vehicles.

Niagara Falls is New York State’s biggest electricity producer

The Robert Moses Niagara Power Plant and Lewiston Pump-Generating Plant together produce up to 2.6 million kilowatts—providing about 20% of New York State’s hydropower and supplying electricity to over 3 million homes.

The world's first geothermal power plant was built in 1913 in Devil's Valley

In Tuscany, Italy, Prince Piero Ginori-Conti of Trevignano established the plant nine years after creating a generator that powered five light bulbs using steam vents in the area. Within three years, a second plant was built with two generators, each with 10 times the energy output of the first.

Most data centers rely on the local power grid to feed power-hungry computer equipment

These facilities house rows of vertical racks containing multiple types of hardware, including servers that provide 24/7 access to online applications, services, and data. In a hyperscale center with thousands of these racks, the annual electricity used is estimated to equal that of 400,000 electric vehicles.

Nuclear power supplies almost half of US carbon-free energy

As of 2023, nearly 20% of US electricity comes from nuclear power, but most reactors were built from 1971 to 1990. Expansion slowed due to safety concerns, high costs, and competition from natural gas.

A dashboard showing real-time electricity usage in the US

The United States demands for electricity are enormous, with hundreds of thousands of megawatt hours required to run households and businesses every hour. You can track the fluctuations of US electric use with this dashboard.

Thomas Edison created the first strand of electric Christmas lights in 1880

Edison strung electric bulbs outside his laboratory in 1880, and his business partner Edward H. Johnson first wrapped a tree in lights in 1882. It wasn’t until the lights were commercialized in 1917 that they became common in household Christmas decorations.

Around 380 underwater cables power the Internet across the world.

On July 29, 1858, two steam-powered battleships met in the middle of the Atlantic Ocean. There, they connected two ends of a 4,000 kilometer (2,500 mile) long, 1.5 centimeter (0.6 inch) wide cable, linking for the first time the European and North American continents by telegraph.

Establishing the wind power grid required incentives, reliability, and affordability

Although wind was harnessed to generate electricity for individual buildings in the late 1800s, high costs, mechanical issues with turbines, and better fossil-fuel alternatives delayed wind power's widespread growth. After the oil crises of the 1970s, governments sought alternative energy sources and, in the decades that followed, provided tax credits to expand the wind power market.

Some renewable energy sources may weaken the resiliency of electric grids by removing outage buffers provided by coal- and natural gas-fired plants, which provide the system with more time to find a new power source if a plant goes down.

The first US stock exchange dates back to the 1790s in Philadelphia

Only two years after that stock exchange in Philadelphia started, the largest stock exchange in the US to date was created: the New York Stock Exchange.

Before Silicon Valley, the American innovation hub was New Jersey

Today, Silicon Valley is known for its dominance in the tech world. But before it rose to prominence, New Jersey was the country's innovation hub. From Thomas Edison's light bulb to the transistor, New Jersey was considered the nation's leader in technology.

Utility companies are often considered 'natural' monopolies

Natural monopolies occur in industries where the upfront costs of entering the market are high, making competition unrealistic. Investor-owned power companies, like Duke Energy, often have natural monopolies, as building alternative power grids and transmission lines is too expensive and impractical for competitors.

Broadway's nickname is 'the Great White Way'

Thanks to the advent of electricity, by the middle of the 19th century, theaters in the Broadway area were illuminated by lampposts and marquees. The nickname “the Great White Way” describes how it looked at night. The term is still used today.

The aging electrical substations of Saigon

One of the overlooked influences of French colonialism in Vietnam lies in the capital city Saigon’s electrical infrastructure. Though France withdrew in the 1950s, many of the colonial-era substations built by the French company Compagnie des Eaux et Électricité are still operational today. Scroll through the article for images of these substations and an overview of their history.

The title of 'World’s Largest Christmas Tree' is disputed

Cities in the US, Italy, Germany, and the Netherlands all claim they have the world’s largest Christmas tree—ranging from massive evergreens, TV and communication towers, and hillside light displays.

Read a complete history of urban mass transit in the United States

Explore the rise and fall of American mass transit, from the horse-drawn omnibus era through the streetcar age to the automobile's dominance. In the 1920s, streetcars carried 12 to 13 billion riders per year. By 1963, that number had shrunken to 300,000.

Learn more about the three sites that powered the Manhattan Project

The Manhattan Project relied on three main sites: Oak Ridge, which enriched uranium; Hanford, which produced plutonium in large reactors; and Los Alamos, which designed and assembled the bombs—work that culminated in the Trinity nuclear test in 1945.

Essential pipes, sewers, and cables lie buried beneath New York City

The Department of Design and Construction offers a tour of its work sites, explaining the complex systems that exist underground. Gas, electrical, telecom pipes, and many others, sprawl out underneath the entire city, with dozens of maps that help workers know where they're placed. This layout is unusual compared to the rest of the country, where wires are often present and visible above ground.

Standard Oil used vertical integration to create an empire

“Vertical integration” is a modern business phrase that refers to a company taking on multiple stages of production—but John D. Rockefeller pioneered it with his Standard Oil company, employing its own plumbers and handling its own oil transportation.

The Electoral College was shaped in part to balance North–South power

This article examines how the Electoral College emerged from political compromise, including efforts to placate slave-owning Southern states and concerns that Northern states would dominate a direct national presidential vote.

The power and influence of the American presidency have expanded significantly over time—far beyond what the founders envisioned.

While the first exchange-traded fund (a 'basket' of different assets that can be bought and sold on a stock exchange) in the US only launched in 1993, the global ETF market has grown to more than $10T in the short time since.

Power lines are dotted with large, brightly colored balls to improve the visibility of these thin wires to helicopters and small planes and help prevent potential crashes.

Hear about the 250-year history of the United States Postal Service, complete with some of its strangest deliveries, important innovations, and the figures that made it an American institution.

The history of many kitchen appliances involves unexpected discoveries and applications, including wartime radar turned hamster defroster and replacing an 'ice king' with heat-stealing boxes.

The rivalry between Alexander Hamilton and Thomas Jefferson centered on federalism—the question of how much power the federal government should hold relative to the states.

Explore an interactive map of battles from the American Revolution, along with detailed summaries of each engagement

How fusion—which releases energy when two lighter atoms combine to form a heavier atom—differs from fission

See this overview of the firework rules across all 50 states, ranging from a complete ban on non-professional fireworks in Massachusetts to states with more lax rules like Indiana.

The American Society of Civil Engineers' infrastructure report card gave the US a C in 2025, its highest grade since the project launched in 1998.

Louisiana's 'Cancer Alley' is infamous for having some of the highest industrial pollution, toxic air emissions, and cancer risks in the US.

See the 25 of the best photos of auroras from around the world.

Before writing 'Walden,' transcendentalist Henry David Thoreau nearly burned down his hometown with a campfire that grew out of control.

Poison ivy was sent to Europe in the 1600s as an exotic, ornamental oddity, where it was purposefully grown in the English royal gardens at Kew, the Faculty of Medicine in Paris, and a few other locations.

'Grand Canyon of the Yellowstone,' a work by American painter Thomas Moran, inspired Congress to establish Yellowstone National Park.

The word 'jazz' evolved from 'jasm,' 19th-century American slang for 'energy'

The price of gas is a composite made up of several different factors, with the federal gas tax making up less than 20% of what drivers pay at the pump.

For centuries, it was common to sleep in two shifts: a few hours at the beginning of the night, and a longer period beginning around midnight

For centuries, Niagara Falls has been a magnet for daredevils seeking to conquer one of nature's most powerful wonders, with its 200-foot drop and water rushing at 32 feet per second with 280 tons of force.

How Amazon operates a 'flywheel' business model, a self-reinforcing cycle that drives continuous growth

See how each of the more than two million known species relates to each other—and to common ancestors—in this zoomable tree of life.

Sony set the standard for cylinder-shaped batteries when it repurposed manufacturing equipment used to make rolls of magnetic recording tape.