Unburned coal stocks at U.S. coal-fired power plants amounted to $6.5 billion, according to a report released by the Institute for Energy Economics and Financial Analysis (IEEFA) on December 16.

This figure was derived from the latest fuel inventory data provided by the U.S. Energy Information Administration (EIA). Coal-fired power plants across the country are consuming roughly 1 million tonnes of coal per day, which is only half of what was used in 2015, the report said.

IEEFA noted that these plants currently hold enough coal to cover about four months' usage averagely, far higher than the typical 50-60 available days.

Coal's contribution to total power generation halved over a decade, hitting about 16%, government data showed.

The EIA revealed that U.S. coal-fired power plants held about 138 million tonnes of coal as of late November, equivalent to expected coal output in 2025 in Appalachia basins. IEEFA based its calculations on a $47.22/t average cost of coal shipped to plants (incl. transportation) in the first nine months this year.

Authors of the report said that holding such high levels of unused coal stocks represents a financial burden for power producers. Low natural gas prices and growing solar and wind generation have eroded the competitiveness of electricity output fueled by coal. Occurrences of higher electricity prices during peak periods also became less frequent.

The decline in coal shipments to power plants has persisted for at least 15 years, dropping from over 80 million tonnes a month in 2008 to about 30 million tonnes in 2024. With substantial coal reserves that utilities should consume, this downward trend is expected to continue in 2025, potentially leading to months with less than 20 million tonnes of intakes, the report said.

Texas and Indiana boast the highest inventories at around 12.3 million tonnes (10% of the total) and 8.8 million tonnes, respectively. State data showed 14 coal-fired power plants are running in Texas and 15 in Indiana.

In its December Short-Term Energy Outlook, the EIA projected U.S. coal consumption to tick up 1% from a year ago to 409 million short tons in 2025, paralleling an expected 1% growth in electric power consumption. This uptick follows a 5% decrease from 2023 to 2024.

Only 3 GW of coal capacity retired so far in 2024, following 11 GW closures in 2023. The EIA forecasted further shutdowns, potentially up to 11 GW in 2025, partly attributed to expanded renewable energy capacities.

IEEFA estimated that up to 13 GW of the remaining 173 GW of coal-fired capacity could be eliminated or converted to natural gas by 2025.

The shift from coal to natural gas continues, with Appalachian Power considering converting two of its coal-fired plants in West Virginia to natural gas to ensure their operations beyond 2032. In Pennsylvania, officials plan to restart the Homer City Generation Station as a gas-fired one, potentially reaching up to 4 GW of generation capacity, making it the largest gas-fired plant in the United States.

Additionally, 25 GW of solar capacity and 9 GW of wind capacity will be added in the coming year, according to the EIA report. The agency stated that increased consumption at operational coal plants and decreased coal production will lead to reduced coal inventories from 131 million short tons by the end of this year to 100 million short tons by late 2025.