The Ames Hydroelectric Generating Plant, constructed in 1890 near Ophir, Colorado, was one of the first (if not the first) commercial system to produce and transmit alternating current (AC) electricity for industrial use and one of the first AC hydro-electric plants ever constructed. It became operational in 1891 and was built by Westinghouse Electric around two of their large alternators. One was set up in the valley as a generator and driven by water. It was connected by a transmission line to the second alternator used as a motor up at the Gold King Mine to drive the mining operation. The facility has been changed and upgraded over the years but is still in operation. It is now on the List of IEEE Milestones. History The need to power a stamp mill to process ore at the Gold King Mine up in the mountains near Ophir, Colorado drove major stock holder Lucien L. Nunn to seek a less expensive alternative to the wood powered steam mill at the site. Timber fuel was in scarce supply at the mines 12,000 foot height and coal could not be used because there was no railroad leading to the mine. The San Miguel River 3000 feet down the slope 3 miles from the mine looked to be a good power source but some of the methods of transmitting the power including water powered compressed air and belt drives did not seem feasible. Lucien's brother Paul, an electrical engineer, began looking into using electric motors to drive the plant. A 220 volt direct current electric system was found to be too expensive due to the size of the copper conductors needed to transmit such a low voltage the distances they were contemplating. A high voltage alternating current system looked more promising so they contacted Pittsburgh, Pennsylvania based Westinghouse Electric in 1890 and convinced them to supply an electricity driven system based on alternating current technology. The AC system was engineered and installed by Westinghouse employees V.G. Converse, Lewis B. Stillwell, Charles F. Scott, and Ralph D. Mershon with the assistance of engineering students they recruited from Cornell University. In the summer of 1890 Westinghouse delivered the equipment and the engineers installed it later that winter. The system consisted of two identical 100-hp Westinghouse single-phase alternators (the largest the company made at the time). One was set up in a generator house, initially just a wooden