The late 19th century was an exciting time for electricity and power distribution. On one side, Thomas Edison championed direct current (DC). On the other side, Nikola Tesla and George Westinghouse advocated for alternating current (AC). This battle over which electric system would power the world became known as the War of the Currents.

Although AC emerged dominant and powers our electricity grids today, DC pioneered early electricity infrastructure and still plays a vital role in our lives. This article explores the War of the Currents and how both AC and DC electricity continue lighting up our world.

Edison's DC System Revolutionized Early Electricity

Thomas Edison is considered the father of modern electricity. In the late 1870s, Edison invented the first practical incandescent light bulb. To power his new invention, Edison researched electricity distribution systems.

At the time, direct current (DC) was the main method for delivering electricity. DC provides a constant voltage or current that flows in one direction. Edison expanded on existing DC power with the first centralized electric power station and distribution system in New York City in 1882.

Edison's Pearl Street Station delivered DC electricity to surrounding homes and businesses. This pioneering system revolutionized electricity, providing convenient lighting and power beyond just batteries. Edison founded the Edison Electric Light Company to commercialize his inventions.

By the late 1880s, Edison's DC systems were lighting major US cities. DC offered simple, low-voltage power ideal for lighting and motors. Edison fiercely promoted DC as the superior and safest electricity delivery system.

AC Power Surges Ahead Thanks to Tesla and Westinghouse

Despite Edison's dominance, AC power emerged as the leading rival to DC. Advances by Nikola Tesla and George Westinghouse drove AC's rise.

In 1885, Tesla partnered with industrialist George Westinghouse to commercialize a complete AC electricity system. Tesla's AC patents covered improved transformers, motors, generators and transmission technology.

AC offered major advantages over DC. Using transformers, AC voltage could be easily increased for efficient long-distance transmission over power lines. Higher voltages enabled more efficient nationwide electricity distribution.

Compared to DC, AC systems could transmit electricity over longer distances without power loss. Westinghouse recognized AC's potential and acquired Tesla's patents, while rapidly building AC generators and distribution.

Bitter Rivalry - The War of the Currents

A nasty rivalry erupted between Edison and Westinghouse as they battled over whose electrical system would power America.

Edison vigorously defended his DC technology and denounced the dangers of high-voltage AC. He held public demonstrations electrocuting animals with AC to discredit the competing system.

Despite Edison's vicious attacks, AC quickly spread as Westinghouse underbid and outpaced Edison's DC systems. In 1893, Westinghouse won the bid to light the Chicago World's Fair, showcasing AC's superiority.

Westinghouse's AC prevailed, and by the 1890s began replacing Edison's DC in cities across America. Better transmitting electricity over long distances made AC the logical choice for national electricity grids.

Although AC decisively won the War of the Currents, DC did not disappear. Edison's direct current remained better for existing infrastructure like streetcars and low-voltage lighting applications.

DC Still Plays a Vital Role in Our Lives

Despite losing the War of the Currents, Edison's DC continues lighting up the modern world along with AC. Today's electricity grid uses AC for efficient high-voltage transmission over long distances. However, DC connects the final link bringing power into our homes and devices.

Behind the wall outlet, AC from the grid flows into a converter that transforms it into low-voltage direct current your devices can use. LED lights, computers, phones and other electronics all require DC to operate.

DC also remains ideal for efficient local electricity distribution. Cities are installing DC microgrids to supplement AC power with resilient, localized energy. DC excels for powering electric vehicles and modern transportation like light rail.

While AC provides the backbone of electricity transmission, both currents play important roles in our infrastructure. The War of the Currents may be over, but AC and DC continue lighting up lives.


The War of the Currents between AC and DC systems was one of the most impactful tech battles in history. Although AC prevailed, both currents lit up our world's electrification. DC pioneered early commercial electricity while AC powers efficient nationwide grids.

Today, AC transmits electricity long-distances, while DC efficiently connects into our homes and devices. Both Edison's direct current and Tesla's alternating current provide the lifeblood of modern civilization. The story reminds us how competition often advances technology for the betterment of all.