With Future Data in Doubt, UMass Amherst Political Economy Research Institute Names Top U.S. Climate Polluters

The Greenhouse 100 Polluters Index ranks companies by their direct emissions of greenhouse gases from U.S.-based facilities. PERI tracks corporate environmental and environmental-justice performance for U.S. industrial activity using uniform, mandated and comparable data from the EPA. The analysis builds on the EPA's facility-level data collection and expands it to the company level-the true decision-making entities.

This year's index is again dominated by fossil fuel-based electric utilities, petrochemical producers and refiners. The top three companies-Vistra Energy, Southern Company and Duke Energy-have held their positions for six consecutive years. Each released more than 70 million metric tons of carbon dioxide equivalent in 2023. Together, they were responsible for nearly 4% of all U.S. greenhouse gas emissions from all sources, including residential, transportation and non-energy sectors.

Rounding out the top 10 are Energy Capital Partners, Berkshire Hathaway, American Electric Power, ExxonMobil, the U.S. government, NextEra Energy and Xcel Energy. ExxonMobil, ranked seventh, is the top company whose emissions are not dominated by electric power generation, releasing 41.7 million metric tons of CO₂-equivalent emissions. Among the top 10, Energy Capital Partners has the highest share of minority residents living within 10 miles of its facilities at 65%, followed by ExxonMobil at 60%.

The index covers publicly traded and privately held firms that appear on lists of leading companies published by Forbes, Fortune and S&P.

"In making this information available, we are building on the historic achievements of the right-to-know movement," Ash adds. "Our goal is to engender public participation in environmental decision-making, and to help residents translate the right to know into the right to clean air, clean water and a livable planet."

The EPA's rollback of reporting and disclosure requirements also threatens other PERI indexes that track companies' release of pollution into the air and water, and near schools.