Who was the worst climate polluter in the US in 2021?

U.S. greenhouse gas emissions from major industrial sources to rise 4.1 percent in 2021, new data shows recently released US Environmental Protection Agency.

The increase is the largest annual rise in emissions recorded in more than a decade of reporting and comes at a time when global climate pollution needs to be cut quickly to limit further warming.

emissions, 2.7 billion metric tons of carbon dioxide equivalent, self-reported more than 8,100 of the nation’s top climate polluters to the agency under the agency’s mandatory greenhouse gas reporting program. Emissions account for about half of all U.S. climate pollution, and the annual update provides the most comprehensive site-by-site assessment of the nation’s top polluters.

The increase in emissions came amid a surge in economic activity and industrial production following the height of the Covid-19 pandemic in 2020. While emissions from major polluters — generally defined as facilities emitting more than 25,000 metric tons of carbon dioxide equivalent per year — rose in 2021, they were 5.25 percent below pre-pandemic levels in 2019 .

Evan Gillespie, a partner at Industrious Labs, a newly formed environmental organization dedicated to decarbonizing heavy industry, said such fluctuations in pollution must stop to meet emissions reduction targets under the Paris climate agreement.

“We can’t have production-related emissions,” Gillespie said. “We will have a lot of work to do over the next eight years to adjust industrial emissions.”

Andy Knott, director of the Sierra Club’s Beyond Coal campaign in the central region of the country, said he’s seeing a lot of progress in shutting down large coal-fired power plants by many, but not all, power companies.

“When I look at the biggest carbon polluters, a lot of them, the utilities that own them, don’t plan to retire them anytime soon at all,” Knott said. “We need to phase out all coal by 2030 and all fossil fuels in the electricity sector by 2035.”

Carbon dioxide is the main driver of climate change, and CO2 emissions from coal-fired and natural gas-fired power plants have been the largest source of emissions. However, other pollutants, including methane, nitrous oxide, and fluorinated greenhouse gases, such as hydrofluorocarbons used in refrigerators and air conditioners, were also significant sources of emissions. These “non-CO2” greenhouse gases are far more potent than carbon dioxide on a pound-for-pound basis, and in many cases remain in the atmosphere for a relatively short time compared to CO2. Curbing their emissions is increasingly seen as the key to stopping rapid warming.

Below is a list of the nation’s top polluters for each of the leading greenhouse gases tracked by the EPA. Also included are some of the highest emissions for different sectors of the economy.

Carbon dioxide: The James H. Miller Jr. Power Plant in Quinton, Alabama was the largest coal-fired power plant in the US in terms of electricity generation in 2021 and was also the largest CO2 emitter in the country. The plant, owned by The Southern Company, emitted 20,834,019 metric tons of carbon dioxide in 2021. Last year, company executives announced plans to stop almost 80 percent of its coal-fired power capacity by 2028 on its way to zero emissions by 2050. The planned shutdowns do not include the James H. Miller plant.

methane: The Bailey Mine, a coal mine owned by Consol Energy in southwestern Pennsylvania, is the largest single source of methane in the US with 90,743 tons of methane emissions in 2021. In the near term, the emissions’ impact on the climate is equal to the annual greenhouse gas emissions of 1.6 million cars, according to the EPA. Consol Energy does capture and destroy some additional methane emissions from the mine as part of the methane abatement pilot program.

Nitrous oxide: Launch of Ascend Performance Materials nylon plant in Cantonment, Florida 24,657 metric tons of nitrous oxide in 2021, four times more nitrous oxide than any other industrial facility in the country, although that figure is still awaiting final EPA verification. The plant produces adipic acid, the main ingredient in nylon 6.6, a strong, durable plastic used in everything from stockings to carpets, seat belts and airbags, and emits large amounts of nitrous oxide, an unwanted byproduct.

Nitrous oxide is 273 times worse for the climate than carbon dioxide on a pound-for-pound basis. Assuming currently reported emissions are correct, emissions from the plant in 2021 would equal the annual greenhouse gas emissions of 1.5 million cars, the EPA said. Other adipic acid plants in the United States and Europe in the late 1990s installed technology to eliminate virtually all nitrous oxide emissions.

Officials of the company told Inside Climate News in early 2020, they will reduce nitrous oxide emissions from adipic acid production by 50 percent by mid-2020 and more than 95 percent by February 2022. However, nitrous oxide emissions from the plant’s adipic acid production rose 38 percent from 2019 to 2021, according to emissions data the company reported to the EPA. Ascend Performance Materials spokeswoman Alison Yang did not directly respond to questions about the increase, but said Ascend has set a goal of reducing greenhouse gas emissions at all of its facilities by 80 percent by 2030.

Hydrofluorocarbons: Hydrofluorocarbon-23 (HFC-23) is 14,600 times more potent as a greenhouse gas than carbon dioxide on a pound-for-pound basis, making it one of the worst climate pollutants ever identified by scientists at the UN’s Intergovernmental Panel on Climate Change . In 2021, chemical manufacturer Chemours released air 180 metric tons HFC-23, a synthetic gas and unwanted byproduct, from its Louisville, Kentucky plant. The emissions that can be destroyed by incineration are equal to the annual emissions of 566,000 cars. However, HFC-23 emissions from the Louisville plant may soon be a thing of the past.

In October 2021 EPA required Chemours will use or destroy 99.9 percent of the HFC-23 it produces by October of this year. Chemours missed a deadline to complete the installation “due in part to supply chain issues,” according to the EPA, which granted the company’s request for Extension for 6 months. The company has installed and is now operating pollution controls, but continues to test and optimize the system, Chemours spokeswoman Cassie Olszewski said.

Sulfur hexafluoride: Sulfur hexafluoride (SF6) is 25,200 times more damaging to the climate than carbon dioxide, making it the most potent greenhouse gas ever assessed by the UN’s Intergovernmental Panel on Climate Change. Once released, SF6 remains in the atmosphere, warming the planet, for 3,200 years. Synthetic gas is used in high-voltage circuit breakers to quickly interrupt electrical current. In 2021, American Electric Power (AEP) released 18 tons of elegas from electrical substations in 10 states, emissions equal to the annual greenhouse gas emissions of 99,000 automobiles. While AEP had the highest overall release rate, Duke Energy Carolinas had the highest SF6 leak rate—6 percent of all the elegas it used in 2021, more than double AEP’s level.

Eighty-eight U.S. utilities are part of a voluntary program that the EPA began acting in 1999 to help utilities reduce SF6 emissions. Duke Energy, the largest U.S. electric utility by revenue, is not part of the program.

“We are certainly working to learn more about the group [and] are reconsidering our participation,” said Duke Energy spokesman Jeff Brooks.

Methane from gas storages: Gas storage compressor station “Petal” has been cleaned 2517 tons of methane from leaky compressors at an underground natural gas storage facility in Petal, Mississippi, in 2021. Emissions from the facility are down 49 percent from the previous year. Still, Petal’s emissions remain nearly double those of any other gas storage facility in the country, despite being a relatively small gas storage facility.

“We are continuing our efforts to reduce methane emissions at Petal and throughout our system,” said Gillian Kirkconnell, a spokeswoman for Boardwalk Pipeline Partners.

Boardwalk owns the Petal gas storage facility as well as the Gulf South Pipeline – Bistineau Station gas storage facility, the nation’s second-largest gas emitter, where the leak occurred 1301 tons of methane in 2021.

Landfill methane: The Sampson County Private Landfill in Roseboro, North Carolina released approx 32,983 tons of methane, more than any other municipal or industrial landfill in 2021, according to company data provided to the EPA. In the near term, the emissions’ impact on the climate is equal to the annual greenhouse gas emissions from 575,000 cars, according to the EPA.

Joy Grahek, executive vice president of strategic initiatives for GFL Environmental, the owner of the landfill, said the company has taken steps to reduce emissions and that the models used by the EPA to estimate emissions are incorrect.

“We implemented a number of different operational and design strategies to minimize landfill methane production, including the use of impermeable cover materials, an extensive gas collection system to capture landfill gas, and flaring of the captured gas,” Grahek said. “It is widely recognized that these models contain significant uncertainty, and using the EPA reports as a basis for ranking the relative performance of landfills in controlling air emissions is imprecise.”

Estimates of landfill emissions vary widely depending on the method operators use to calculate their emissions and may underestimate actual emissions by “a factor of two.”

EPA recently proposed changes on how to better calculate methane emissions from landfills.