The Department of Energy reported Wednesday that coal exports saw a rare rebound amid higher demand due to higher prices for other energy sources.

In its monthly outlook for the energy market, the Energy Department found that coal exports were up 29%. Globally, energy prices have increased owing to higher costs for oil and gas, whereas coal remains a cheaper though dirtier power source.

The U.S. is not immune from the increase in coal use despite the promises of the Biden administration to hasten the shift towards a decarbonized energy grid. According to the report, domestic consumption of coal is expected to be 18% higher than it was in 2020. In a previous Energy Department report, the last time coal saw a year-on-year increase was in 2014.

News that coal exports and demand at home has risen comes at a time when Biden pledged to world leaders that his administration took the fight against global climate change very seriously. Speaking at the COP26 global climate conference in Glasgow, Scotland, on Nov. 1, Biden promised that the U.S. would lead by example in meeting its climate commitments.

Since entering office, Biden has unveiled a number of initiatives to move the U.S. closer to renewable and clean energy technologies. Included in the recently passed $1.2 trillion infrastructure package is $50 billion in climate resilience measures and $65 billion in clean energy and grid-related investments.

However, his climate agenda has remained hobbled in Congress over disagreements within his own Democratic Party and seemingly contradictory approvals from Biden for new oil and natural gas projects at home.