First long-distance AC transmission from the Ames power plant

Background. Lucien L. Nunn, a major stockholder in the Gold King Mine, sought to power a stamp mill for ore processing. The high cost of coal for steam generation drove him to seek alternative power sources. His brother Paul, an electrical engineer, investigated electric motors. They determined that a high-voltage alternating current system was more promising than existing options.

Construction. In 1890, the Nunn brothers contacted Westinghouse Electric in Pittsburgh to supply an electricity-driven system based on alternating current technology. Westinghouse delivered the equipment in the summer of 1890, and engineers installed it later that winter. The plant was constructed near Ophir, Colorado, using two large Westinghouse alternators.

Technical Significance. The plant became operational in June 1891. It was the first successful demonstration of long-distance transmission of industrial-grade alternating current power. The system used two 100 hp Westinghouse alternators, one as a generator producing 3,000 volts, 133 Hertz, single-phase AC, and the other as an AC motor. It predated the Westinghouse plant at Niagara Falls by four years, and is described as one of the oldest power plants to produce and transmit alternating current for industrial purposes.