Old Coal Plant Neared Retirement, but Now It’s Needed to Keep the Lights On

The Midcontinent Independent System Operator, or MISO, which oversees a grid spanning much of the Midwest, moved this week to halt Rush Island’s closure this fall. It warned earlier this year that the region faces the risk of rolling blackouts this summer because it might not have enough supplies to meet demand surges on hot days.

The Rush Island plant is one of the country’s largest emitters of sulfur dioxide, and it has long faced criticism from environmentalists, health experts and neighbors because its operations have been linked to health problems in the surrounding community. A federal judge in 2017 determined that Ameren violated the Clean Air Act by failing to install pollution controls before an overhaul of the plant and later ordered the company to do so retroactively.

Ameren estimated that compliance with the judge’s order would cost as much as $1 billion and moved to retire the plant by September in lieu of making the upgrades.

Now, Ameren said in a court filing this week that it likely would have to keep the plant online through September 2025 because MISO determined that closing the plant this year would result in reliability risks. The company said it expects the grid operator to designate the plant as a so-called system support resource, a last-resort measure to ensure adequate electricity supplies during periods of peak demand.

MISO and Ameren declined to comment.

Ameren said in its court filing that it is working on upgrades to its high-voltage power lines to help alleviate MISO’s reliability concerns, work that Ameren expects to take just over three years. Ameren in its filing asked the judge overseeing the case to permit the plant to operate on a limited basis with a cap on sulfur dioxide emissions at roughly half of current levels, allowing the company to forgo investment in pollution controls as it prepares for the later retirement.

Grid operators across the U.S. are leaning more heavily on old coal- and gas-fired power plants as electricity demand threatens to exceed supply during periods of extreme heat and other severe weather, events exacerbated by climate change. In addition to MISO, grid operators in Texas and California have lately warned of the potential for rolling blackouts this summer, in part because traditional power plants are being retired more quickly than they can be replaced by renewable energy and battery storage.

Conventional power plants such as Rush Island can help fill supply gaps during periods when wind and solar farms, which are among the cheapest and cleanest sources of electricity, aren’t producing at full capacity as a result of the weather, or when other generators fail or go offline for maintenance. But the decision to keep the old plants operating creates other concerns because their emissions contribute to climate change and pose potential health risks for people who live nearby.

“It is sadly ironic that the grid operator says Ameren’s uncontrolled coal-burning power plant is needed for reliability because of possible capacity limitations due to extreme heat and drought caused by climate change,” said Jenn DeRose, a Beyond Coal Campaign representative for the Sierra Club, which intervened in the Rush Island case. “Climate change is caused in the first place by burning fossil fuels like coal.”

Rush Island, near the small Missouri city of Festus, emits an average of about 18,000 tons of sulfur dioxide a year, court filings show. It also emits substantial amounts of carbon dioxide, as well as nitrogen oxides and other pollutants.

The judge overseeing the case against Ameren, initiated by the Environmental Protection Agency, determined that the plant’s sulfur dioxide emissions were enough to increase the risk of premature death stemming from health problems associated with poor air quality.

“If that facility is going to continue operating, it cannot continue operating at current emissions levels,” said Stephanie Kodish, senior director at the National Parks Conservation Association, which monitors state air quality plans.

Former Festus mayor Joe Grohs, 70, said he has long felt that the Rush Island plant had taken a toll on the health of the surrounding community, which he likened to “the Bermuda Triangle of pollution and cancer.” After losing his sister and parents to cancer, Mr. Grohs said he became much more aware over the years of the effect that coal plants and other industrial activities have on air and water quality.

Mr. Grohs said that if the plant must keep operating for reliability reasons, he would like to see Ameren replace it as soon as possible with energy from renewables. He estimated that 70% of his high school class moved away and never returned, in part because of pollution problems.

“If you have ever breathed clean air, you know the difference,” he said. “If you have never breathed clean air, you don’t.”

Write to Katherine Blunt at [email protected]

The Midcontinent Independent System Operator, or MISO, which oversees a grid spanning much of the Midwest, moved this week to halt Rush Island’s closure this fall. It warned earlier this year that the region faces the risk of rolling blackouts this summer because it might not have enough supplies to meet demand surges on hot days.

The Rush Island plant is one of the country’s largest emitters of sulfur dioxide, and it has long faced criticism from environmentalists, health experts and neighbors because its operations have been linked to health problems in the surrounding community. A federal judge in 2017 determined that Ameren violated the Clean Air Act by failing to install pollution controls before an overhaul of the plant and later ordered the company to do so retroactively.

Ameren estimated that compliance with the judge’s order would cost as much as $1 billion and moved to retire the plant by September in lieu of making the upgrades.

Now, Ameren said in a court filing this week that it likely would have to keep the plant online through September 2025 because MISO determined that closing the plant this year would result in reliability risks. The company said it expects the grid operator to designate the plant as a so-called system support resource, a last-resort measure to ensure adequate electricity supplies during periods of peak demand.

MISO and Ameren declined to comment.

Ameren said in its court filing that it is working on upgrades to its high-voltage power lines to help alleviate MISO’s reliability concerns, work that Ameren expects to take just over three years. Ameren in its filing asked the judge overseeing the case to permit the plant to operate on a limited basis with a cap on sulfur dioxide emissions at roughly half of current levels, allowing the company to forgo investment in pollution controls as it prepares for the later retirement.

Grid operators across the U.S. are leaning more heavily on old coal- and gas-fired power plants as electricity demand threatens to exceed supply during periods of extreme heat and other severe weather, events exacerbated by climate change. In addition to MISO, grid operators in Texas and California have lately warned of the potential for rolling blackouts this summer, in part because traditional power plants are being retired more quickly than they can be replaced by renewable energy and battery storage.

Conventional power plants such as Rush Island can help fill supply gaps during periods when wind and solar farms, which are among the cheapest and cleanest sources of electricity, aren’t producing at full capacity as a result of the weather, or when other generators fail or go offline for maintenance. But the decision to keep the old plants operating creates other concerns because their emissions contribute to climate change and pose potential health risks for people who live nearby.

“It is sadly ironic that the grid operator says Ameren’s uncontrolled coal-burning power plant is needed for reliability because of possible capacity limitations due to extreme heat and drought caused by climate change,” said Jenn DeRose, a Beyond Coal Campaign representative for the Sierra Club, which intervened in the Rush Island case. “Climate change is caused in the first place by burning fossil fuels like coal.”

Rush Island, near the small Missouri city of Festus, emits an average of about 18,000 tons of sulfur dioxide a year, court filings show. It also emits substantial amounts of carbon dioxide, as well as nitrogen oxides and other pollutants.

The judge overseeing the case against Ameren, initiated by the Environmental Protection Agency, determined that the plant’s sulfur dioxide emissions were enough to increase the risk of premature death stemming from health problems associated with poor air quality.

“If that facility is going to continue operating, it cannot continue operating at current emissions levels,” said Stephanie Kodish, senior director at the National Parks Conservation Association, which monitors state air quality plans.

Former Festus mayor Joe Grohs, 70, said he has long felt that the Rush Island plant had taken a toll on the health of the surrounding community, which he likened to “the Bermuda Triangle of pollution and cancer.” After losing his sister and parents to cancer, Mr. Grohs said he became much more aware over the years of the effect that coal plants and other industrial activities have on air and water quality.

Mr. Grohs said that if the plant must keep operating for reliability reasons, he would like to see Ameren replace it as soon as possible with energy from renewables. He estimated that 70% of his high school class moved away and never returned, in part because of pollution problems.

“If you have ever breathed clean air, you know the difference,” he said. “If you have never breathed clean air, you don’t.”

Write to Katherine Blunt at [email protected]