The advent of alternating current power, or AC, marked a revolutionary leap in electrical engineering, fundamentally altering how electricity was generated, transmitted, and utilized. The installations of the Ames Hydroelectric Generating Plant near Ophir, Colorado, and the Durango Power Plant in Durango, Colorado, were central to this transformation. Both plants contributed to the practical application of AC systems, playing crucial roles in the broader narrative of electrical power amid the intense “war of currents” between AC and direct current, or DC.
Constructed between 1890 and 1891, the Ames Hydroelectric Generating Plant emerged from the specific challenges posed by the Gold King Mine, located in the rugged San Juan Mountains. Due to timber scarcity and logistical transportation challenges, traditional power sources like wood and coal proved impractical. Seeking a sustainable solution, Lucien L. Nunn, a significant stockholder in the mine, turned to electricity and initially considered a 220-volt DC system but quickly realized that the cost of large copper conductors over long distances made this approach unfeasible. Pivoting to a high-voltage AC system, Nunn enlisted Westinghouse Electric, a pioneer in AC technology. The installation featured two large single-phase alternators—among the largest produced at that time—powered by a Pelton wheel that converted the kinetic energy of local streams into electricity.
The Gold King Mill opened on June 19, 1891, and was powered by electricity from the Ames Plant, which proved a technological marvel. The power generated was transmitted over a 2.6-mile stretch of bare copper wire, illustrating the cost-effective advantages of AC over DC systems. The plant underwent upgrades in 1896, transitioning to a two-phase system capable of transmitting 10,000 volts, thereby extending the reach of its electrical output. This evolution underscored the Ames Plant’s pivotal role in establishing the feasibility of hydroelectric power generation and its contribution to the broader adoption of AC technology. The facility has been upgraded over the years but is still in operation in its original location and owned by Xcel Energy.
In 1892, just a year after the Ames Plant began operations, the Durango Light and Power Company installed two new AC generators at its original location at 7th Street, east of the railroad tracks. They also announced the building of a new facility at 14th and Camino del Rio. A group of citizens established the Durango Light and Power Company on November 11, 1885, and introduced electricity to Durango in 1887. Durango Light and Power initially utilized DC before embracing the fledgling technology of AC power in the new plant, which was completed in 1893, investing in what many considered a risky endeavor. 
At the time, AC systems were villainized in some eastern cities due to concerns about their safety. Many New York City streets were kept in darkness one winter after AC lines were down. Yet, the new Durango Power Plant quickly became an integral part of the town’s infrastructure, powering streetlights and laying the groundwork for the area’s electrical needs long before cities in the East had access to similar technologies.
As the town of Durango developed, the plant evolved to meet its growing demands for electricity. Eventually, it became part of the Western Colorado Power Company, supplying electricity to a wide swath of Colorado’s Western Slope. In the mid-1940s, reflecting changing energy paradigms, the Durango Power Plant transformed significantly from coal-fired to gas-fired power generation. The Durango Power Plant was housed in a Mission-style brick building—a groundbreaking architectural choice for commercial construction. It’s the sole known surviving intact plant of its kind in the United States.
The histories of the Ames Hydroelectric Generating Plant and the Durango Power Plant encapsulate the innovative spirit of the late 19th century and the transformative power of AC technology. The Ames Plant demonstrated the practicality of hydroelectric power and played a critical role in the eventual widespread acceptance of AC systems. At the same time, the Durango Power Plant showcased the adaptability and enduring significance of early electrical infrastructure. Together, these plants highlight the journey of AC power from a novel technology to a cornerstone of modern electrical systems and a huge step toward finding sustainable energy solutions. Their legacies continue to influence the energy landscape today, standing as monuments to the ingenuity and resilience of their time.
Discover more about Southwest Colorado’s history of electrification at the Western Colorado Power Company Collection at the Center of Southwest Studies.
