Coal production in the U.S. could range from flat to continuing declines through 2040, according to the Energy Department's Energy Information Administration (EIA).

Electric power generation accounts for more than 90% of U.S. coal demand, and domestic coal production has declined over the past decade as coal has been displaced by natural gas and renewable energy resources in electric generation.

EIA’s Annual Energy Outlook 2017 includes cases with alternative assumptions about U.S. environmental policy and levels of oil and natural gas resource development and technological advancement. Across these cases, the outlook for coal varies based on its relative economics compared with natural gas and renewables in the power sector.

The reference case, which is designed to apply all current laws and regulations (including the Obama-era Clean Power Plan), forecasts U.S. coal production declining from 740 million short tons (MMst) in 2016 to 620 MMst in 2040. By 2040, U.S. coal production drops to roughly half the level of peak coal production reached by the United States in 2008.

Coal generation and production are significantly higher in projections that include the end of the Clean Power Plan. As a result, coal production stabilizes at about 900 MMst from 2025 through 2040.

The adoption of assumptions that reflect an optimistic outlook for natural gas supply lowers projected coal use. Here, EIA forecasts that coal production declines to 500 MMst in 2040 as natural gas-fired generation outcompetes coal-fired generation in all years.

The end of the Clean Power Plan may offer the most optimistic outlook for coal.The end of the Clean Power Plan may offer the most optimistic outlook for coal.Nuclear generation is also somewhat lower in this case through 2040, as the absence of the Clean Power Plan moves more coal into the lower-cost segment of the dispatch order, EIA says. Market-clearing dispatch prices, which are already held down by low natural gas prices, fall even lower, leading to some additional retirements of nuclear power plants.

To the extent that operators decide not to retire additional nuclear capacity, the higher amount of coal generation that occurs in the absence of the Clean Power Plan would be partially offset by reductions in natural gas and renewable generation.

In EIA's reference case, about 96 gigawatts (GW) of the existing fleet of 265 GW of coal-fired electric generating capacity in 2016 is projected to retire or convert to natural gas by 2040. EIA says that is "very close" to the 93 GW of coal-fired capacity projected to retire or convert under high resources and technology assumptions without the Clean Power Plan.

Few coal-fired power plants have been added in recent years, and in all of the EIA cases that were modeled, no new coal-fired generating capacity was added. In all cases, annual coal production remains below the 1,000 MMst level last seen in 2014.