Two of America’s largest coal plants are shutting down this year and next. Coal has become more expensive to domestically exploit than natural gas since hydraulic fracturing became popular in the early 2000s. The hundreds of coal-fired plant closures that have occurred in recent history may be the signs of a shifting economy dependant on natural gas.

Dan Bakal, a senior director at the sustainability nonprofit Ceres, told the Scientific American that these closures are a sign that “the economics keep moving in a direction that favors natural gas and renewables. Five years ago, it was about the older coal plants becoming uneconomic… Now, it’s becoming about every coal unit, and it’s a question of how long they can survive.”

Navajo Generating Station

For decades, the Navajo Generating Station provided electricity to utility companies in Arizona, Nevada, and California. It also provided power to the Central Arizona Project, which diverted water from the Colorado River to central and southern regions of Arizona. The plant, operated by the Salt River Project, in Arizona failed after a two-year search to find new ownership. It will finish burning the remaining supply of coal and then close its doors for good. The coal mine that supplied it, the Kayenta mine 70 miles away, was exclusive to Navajo Generating Station. Therefore, it too closed. The last load of coal delivered to the station was in August 2019.

The decision to close came in 2017 when owners found they were losing money each time the plant went into production and couldn’t find buyers to take it over. This closure follows an already dialed-back use of the plant and the increased purchase of other energy sources by owners (mainly in the utility market). The federal and non-federal, utility owners of the Navajo Generating Station are the U.S Bureau of Reclamation, the Salt River Project, Arizona Public Service, NV Energy, and Tucson Electric Power.

The three-unit Navajo Generating Stating is a 2.25-megawatt coal plant leased from the Navajo Nation’s tribal trust lands in Page, Arizona. It was first commissioned in 1974 and cost nearly $2.3 billion dollars to construct (in 2018 dollars).

Bruce Mansfield

Owned by FirstEnergy Solutions, the Bruce Mansfield plant in Shippingport, Pennsylvania is another big-dog coal-fired power plant that is scheduled to be deactivated. Currently, two of the three units have already been shut down, which leaves only 830-megawatts of its total 2.4-megawatt coal capacity. This final unit is expected to be diminished and retired by the summer of 2021.

The story of Bruce Mansfield is a similar song to the Navajo Generating Station and other coal-fired plants in the United States: It simply is no longer economically viable for the company to keep it running.

Prior to the closing of the first two units, Bruce Mansfield was the biggest coal-fired plant in Pennsylvania and the largest one that FirstEnergy owned. When running at full capacity, the plant generated 59-million kilowatt-hours of electricity per day. It came online in 1976, shortly after the Navajo Generating Station was commissioned.

Other stations to shut down

Since 2010, 289 coal plants have shut down in the United States, or 40 percent of coal-generated power in the country. Currently, about 240 remain open. Coal production has faltered since the early 2000s, peaking in 2008. Since then, coal production has dropped by a third. It is expected to continue to fall. Where it was at one time nearly 40 percent of the U.S. energy, coal now accounts for 25 percent of power.

However, according to the Energy Information Administration, natural gas is picking up the slack left by retired coal plants. Most recent numbers find that natural gas makes up 40 percent of the domestic power supply.

Sources

Phys.org (2019). “50 US coal power plants shut under Trump”

Catherine Morehouse (2019). “Last GW of 2.25 GW coal-fired Navajo Generating Station expected to shut down any day now,” Utility Drive

Ryan Randazzo (2019). “What to know about the closure of the Navajo coal plant and mine,” AZ Central

Paul Gough (2019). “Bruce Mansfield deactivation begins,” Pittsburg Business Times

FirstEnergy Corp. “Bruce Mansfield Plant”