Electrification

Lore & Background

Electrification was called 'the greatest engineering achievement of the 20th Century' by the National Academy of Engineering. It continues in both rich and poor countries. Electric lighting was highly desirable—much brighter than oil or gas lamps, with no soot, and far cheaper and more convenient. Some companies were able to pay for electricity with insurance savings due to its safety.

Before electric power, steam engines needed to be several hundred horsepower to be efficient, and the smallest commercial steam engines were about 2 horsepower, often above the need for small shops. A small steam engine and boiler could cost as much as $7,000, while a living horse could be had for less than a tenth that price. Man-powered tools and even dogs on treadmills were used for tasks. Electric motors were several times more efficient than small steam engines and more efficient than human or animal power.

Electrification and economic growth are highly correlated. In the U.S. from 1870 to 1880, each man-hour was provided with 0.55 hp; by 1950, each man-hour was provided with 5 hp. The period of electrification of factories and households from 1900 to 1940 was one of high productivity and economic growth. However, in some regions, electrification was shaped by colonial politics—in India, linguistics-based regional politics led to two separate grids; in colonial Zimbabwe, electrification was racially based; in Mandate Palestine, British electric concessions deepened economic disparities between Arabs and Jews.

Reader's Guide

Electrification is a foundational process in modern history, recognized as the greatest engineering achievement of the 20th century. It transformed manufacturing, households, and transportation by replacing steam, animal, and human power with efficient electric motors and lighting. The economic impact was profound: in the U.S., horsepower per man-hour increased from 0.55 in 1870–1880 to 5 in 1950, correlating with high productivity growth from 1900 to 1940. However, electrification's benefits were unevenly distributed, with colonial and political factors shaping access in regions such as India, Zimbabwe, and Mandate Palestine. Today, electrification is central to sustainable energy, involving the build-out of smart grids and the electrification of transport (electric vehicles) and heating (heat pumps). While about 840 million people still lacked access in 2017, global electrification rose from 49% of the world's population in 1970 to 81–83% by the early 2010s. The shift to renewable electricity and electrified end-uses is key to reducing carbon emissions, with technologies like heat pumps and solar photovoltaics offering economic and environmental benefits.

Did You Know?

• Electrification was called 'the greatest engineering achievement of the 20th Century' by the National Academy of Engineering.
• In the late 19th century, specially designed power buildings leased space to small shops, supplying power from a steam engine through line shafts.
• Electric motors had a conversion efficiency of 4–5% compared to 30% with coal power.
• In 2017, about 840 million people had no access to grid electricity, down from 1.2 billion in 2010.