Ameren Corp. intends to close its 1,218-MW Rush Island coal-fired power plant in Missouri years ahead of schedule, saying it is in the best interests of customers and other stakeholders.
The decision "will have a much more beneficial environmental impact, on a far shorter timeframe," than the company's previous plans to add new emissions controls to the two-unit plant, subsidiary Ameren Missouri, known legally as Union Electric Co., said in a Dec. 14 court filing.
The company did not specify when it will close the facility but said it would do so by March 30, 2024, the deadline set by a federal district court for Ameren to install desulfurization technology.
Ameren planned to operate Rush Island until 2039 and install a wet flue gas desulfurization system to comply with the 2019 ruling by the U.S. District Court for the Eastern District of Missouri. The first of two units at the plant in Jefferson County, Mo., began operating in 1976. But the district court issued a stay while Ameren appealed the ruling to the U.S. Court of Appeals for the 8th Circuit, which ultimately upheld (No. 19-3220) the lower court's order in relation to Rush Island.
"The decision to accelerate the retirement of the Rush Island Energy Center comes after carefully considering our legal, operational and regulatory alternatives, as well as the impact on customer costs and system reliability," Ameren Missouri Chairman and President Marty Lyons said in an emailed statement. "We remain committed to reliable and affordable electric service for the benefit of our customers and communities while reducing emissions and building on our longstanding commitment to environmental stewardship."
The plant's largest sources of coal in 2021, according to S&P Global Market Intelligence data, have been Eagle Specialty Materials LLC's Belle Ayr mine and Arch Resources Inc.'s Black Thunder mine, both in Campbell County, Wyo.
In its Dec. 14 court filing, Ameren attributed the decision to "changed circumstances" since the district court's ruling in 2019. Those new circumstances include updated forecasts for natural gas prices, the likelihood of future carbon dioxide regulations, legislative developments in Missouri and "an increased emphasis on environmental, social and governance considerations by a wide range of stakeholders."
But Ameren said the early retirement of Rush Island is "not a simple matter." The Midcontinent ISO must first assess the potential grid stability and reliability impacts of the new closure target. That review process is already underway, with an initial assessment expected in mid-January 2022.
Along with many other utilities, Ameren set a goal to produce net-zero carbon emissions by 2050 across all its operations in Illinois and Missouri. As part of that plan, the company has pledged to invest $4.5 billion to install 3,100 MW of wind and solar generation by 2030, as well as implement energy efficiency and demand response programs that could shave almost 2,000 MW from peak energy demand by 2040.
