The rise of natural gas production has most significantly impacted coal.

The rise of natural gas production, particularly due to the expansion of hydraulic fracturing (fracking), has had a major impact on coal in the U.S. Natural gas is now a cheaper and cleaner alternative to coal for electricity generation. As a result, many power plants have switched from coal to natural gas, leading to a decline in coal consumption and production. The shift is driven by natural gas's lower carbon emissions and the abundance of shale gas, which has made it a more competitive fuel for power generation. This transition has been a key factor in reducing U.S. carbon emissions in recent years.