An anonymous reader quotes a report from Ars Technica: At 2.25 gigawatts, Arizona's Navajo Generating Station is the biggest coal-burning power plant in the Western U.S. The plant, and the nearby Kayenta coal mine that feeds it, are located on the Navajo Indian Reservation, and the Navajo and Hopi peoples have had a conflicted relationship with coal since the plant opened in the 1970s. Almost all the 900-plus jobs at the mine and plant are held by Native Americans, and the tribes receive royalties to account for large portions of their budget. Negotiations were underway to improve the tribes' lease terms, which expire in 2019. But on Monday, the four utilities that own most of the plant voted to close it at the end of 2019. They decided that the plant's coal-powered electricity just can't compete with plants burning natural gas. A press release from Salt River Projects, which runs the plant, explained, "The decision by the utility owners of [Navajo Generating Station] is based on the rapidly changing economics of the energy industry, which has seen natural gas prices sink to record lows and become a viable long-term and economical alternative to coal power."