Fossil fuel power generation

FILE - In this Tuesday, Nov. 6, 2018 file photo, Iowa Attorney General Tom Miller gives his acceptance speech at the Iowa Democratic election night party, in Des Moines, Iowa. Miller, a supporter of clean energy policies reducing greenhouse gases as a way to battle global climate change, said Wednesday, Aug. 14, 2019, he was blocked by Republican Gov. Kim Reynolds from joining 21 other states in suing the Trump administration over a policy that relaxes restrictions on coal-fired power plants. (AP Photo/Matthew Putney, File)

FILE - In this July 27, 2018, file photo, the Dave Johnson coal-fired power plant is silhouetted against the morning sun in Glenrock, Wyo. A coalition of 22 Democratic-led states has sued the Trump administration over its decision to ease restrictions on coal-fired power plants. The lawsuit, filed in the U.S. Court of Appeals for the District of Columbia Circuit, says the new rule violates the federal Clean Air Act because it does not meaningfully replace power plants' greenhouse gas emissions. (AP Photo/J. David Ake, File)

FILE - In this Feb. 1, 2016 file photo, a bald eagle takes flight at the Museum of the Shenandaoh Valley in Winchester, Va. While once-endangered bald eagles are booming again in the Chesapeake Bay, the overall trajectory of endangered species and the federal act that protects them isn't so clearcut. (Scott Mason/The Winchester Star via AP, File)

Dozens of environmentalists block the main entrance of the coal-fired power plant in Mannheim, Germany, Aug. 3, 2019. People are blocking the entrance to a coal-fired power plant in the German city in protest over the burning of fossil fuels. Mannheim police said about 40-50 protesters have been staging the blockade since in the early hours of Saturday. (Uwe Anspach/dpa via AP)

United Nations Secretary General Antonio Guterres, right, follows the UAE Youth Minister, Shamma Al Mazrim as they take the stage at the opening ceremony of the United Nations climate change summit in Abu Dhabi, United Arab Emirates, Sunday, June 30, 2019. (AP Photo/Kamran Jebreili)

European Commission President Jean-Claude Juncker, right, and European Council President Donald Tusk, left, are escorted by Japanese Prime Minister Shinzo Abe prior to their working lunch on the sidelines of the G20 Summit at the International Exhibition Center in Osaka, Japan, Thursday, June 27, 2019. (Franck Robichon/Pool Photo via AP)

FILE - In this July 27, 2018, file photo, the Dave Johnson coal-fired power plant is silhouetted against the morning sun in Glenrock, Wyo. The Trump administration announced on Wednesday, June 19, 2019, that it has rolled back a landmark Obama-era effort targeting coal-fired power plants and their climate-damaging pollution. (AP Photo/J. David Ake, File)

Acting White House Chief of Staff Mick Mulvaney, left, shakes hands with EPA administrator Andrew Wheeler after Wheeler signed the Affordable Clean Energy Rule at the Environmental Protection Agency, Wednesday, June 19, 2019, in Washington. Wheeler signed a repeal of one of the Obama era's two biggest climate change initiatives, the Clean Power Plan, and adopting an alternative plan that would loosen regulations on the plants. (AP Photo/Alex Brandon)

FILE - In this Feb. 26, 2019, file photo, former New York City Mayor Michael Bloomberg speaks at a news conference at a gun control advocacy event in Las Vegas. Bloomberg is plunging $500 million into an effort to move the United States to a 100% clean energy economy and close all of the nation’s remaining coal plants by 2030. According to the mayor’s team, The billionaire Bloomberg’s investment in the Beyond Carbon initiative marks the largest ever philanthropic effort to combat climate change. (AP Photo/John Locher, File)