New federal projections show that, for the first time, more electricity in the country will come from renewable sources like solar and wind than from coal. And environmentalists say that's having a positive impact on air quality in Massachusetts.

The report, from the U.S. Energy Information Administration (EIA), projects U.S. coal consumption to decrease by 23 percent this year, partly due to a substantial drop in demand for electricity due to the economic shutdown.

At the same time, the EIA expects renewable energy to be the fastest-growing source of electricity generation this year, although the economic slowdown is likely to slow the construction of new solar and wind projects.

“It's an historic moment in which we've seen the decline and impending demise of coal, as renewables nationally and within this region have surpassed it, both in the numbers of generating plants, but also, more importantly, how much power they're generating on a daily basis,” said Greg Cunningham, vice president and director of the Clean Energy and Climate Change Program at the Conservation Law Foundation.

"During this COVID-19 period, with the unfortunate reduction in economic activity, there has been a fairly serious decline in demand, and also in emissions," Cunningham said.

There aren't any coal-burning power plants in Massachusetts, but he says the emissions reduction directly impacts the state.

"As we've seen a decline in emissions of coal nationally — and from those who are upwind of us — our air quality has improved," Cunningham said.

Those emissions from plants in other states like Ohio and Illinois, include carbon dioxide (CO2), which is contributing to global climate change.

Emissions from midwestern coal-fied plants were part of what led to the landmark 2007 Supreme Court decision in Massachusetts v. EPA, in which the Supreme Court ruled the Clean Air Act requires the agency to regulate greenhouse gases. The Obama administration adopted the Clean Power Plan in 2015, setting limits on carbon pollution from power plants. In 2019, Massachusetts joined 22 other states in suing the Trump administration for rolling back those limits.

The EIA report forecasts that U.S. energy-related CO2 emissions will decrease by a record 11 percent in 2020 as a result of slowing economic growth related to COVID-19.

This doesn't mean, however, that emissions from coal-fired plants are permanently down. The report predicts that, as the economy recovers and stay-at-home orders are lifted, C02 will increase by 5 percent in 2021 as some idled coal-fired plants are brought back online to meet demand. Still, the report predicts that coal will continue to decline over the long term.