How Edison's Failed DC Power Grid Actually Revolutionized Home Wiring

Thomas Edison was one of history’s most prolific inventors, with over 1,000 patents to his name. While Edison is best known for inventing the phonograph and developing commercially-viable electric light, one of his most ambitious and ultimately unsuccessful projects was actually critical in shaping modern home electrical systems.

Edison’s Push for DC Power Distribution

In the late 1870s and 1880s, Edison focused intensely on developing a practical way to distribute electricity for lighting and power in American homes and businesses. At the time, electricity was a novelty, with no infrastructure in place for widespread delivery to homes and cities.

Edison was determined to develop a direct current (DC) system for electric power distribution:

To enable DC power delivery, Edison:

However, DC systems faced major technical limitations that prevented large-scale adoption:

Ultimately the limitations of DC meant it was impractical for delivering electricity across towns and cities. AC power distribution backed by Nikola Tesla and George Westinghouse would become the dominant standard.

How Edison’s DC Work Shaped Electrical Wiring

Although DC lost the “War of Currents” to AC power systems, Edison’s pioneering work was not in vain. In fact, the 100V DC standard he created for indoor lighting systems went on to directly influence modern low voltage household electrical wiring:

Edison’s low voltage DC approach turned out to be remarkably well-suited for indoor electrical wiring. The use of low voltage AC based on his DC work provides critical safety and efficiency benefits:

So while DC was not viable for large scale power distribution from central stations, Edison’s low voltage approach was a key foundation for safe, efficient electrical wiring within the home. Even as AC grids spread rapidly across America in the early 1900s, the 120V standard pioneered for DC by Edison remained the ideal for indoor use, powering homes into the modern area.

The Battle of The Currents - AC vs DC

The fierce competition between Edison advocating for DC systems and Westinghouse/Tesla promoting AC is known as the "War of the Currents." This battle in the late 1880s was one of the most intense technology rivalries in history:

AC advantages over DC for power grids:

AC decisively won the battle by the 1890s. Westinghouse won the bid to light the Chicago World's Fair of 1893 using AC, demonstrating its viability. The advantages of AC allowed rapid consolidation of electric utilities using universal AC grids.

Despite losing the overall “Current War,” Edison’s contributions were still immensely influential. AC may have won the battle for transmission, but Edison’s DC low voltage standard went on to win the wiring for lighting homes and buildings across America.


While Edison failed to make DC the dominant electrical distribution system, his early standard of 100V DC for indoor lighting directly informed the 120V 60Hz AC standard still used for household wiring today. The low voltage approach pioneered by Edison for his DC lighting systems proved ideal for preventing electrical hazards, enabling efficient insulation, and powering motors and appliances. So even though AC triumphed for the grid, the war over currents still led to Edison’s DC work revolutionizing how we wire our homes and bring electricity indoors today.