Oliver B. Shallenberger

Oliver Blackburn Shallenberger was an American electrical engineer who lived from May 7, 1860 to January 23, 1898 and spent his career at Westinghouse Electric. After noticing a spring set spinning by electromagnetic force during a laboratory accident, he built on the effect to invent the induction watt-hour meter in 1888, the first successful meter able to measure alternating-current use accurately enough to bill customers for the power they actually consumed. The meter sold roughly 120,000 units within its first decade and helped settle the war of currents in favor of alternating current by giving AC utilities a practical way to charge for what they sold, something direct-current systems had long been able to do. Shallenberger also worked out methods for running multiple AC generators together on a single circuit and designed transformer-based street lighting systems, and died in Colorado at only thirty-seven.