The 18-year dataset tells a clear story of accelerating coal uneconomics. In 2008, all 149 coal operators were uneconomic vs gas — Henry Hub averaged $8.86/MMBtu, making gas generation dramatically more expensive than coal. The shale revolution reversed this: by 2012 and 2015–2016, with gas at $2.52–2.66/MMBtu, only 16–22 operators were past the switching threshold. Coal appeared economically secure.
That security proved temporary. In 2022, 96 of 104 remaining coal operators were uneconomic as gas spiked to $6.42/MMBtu following Russia's invasion of Ukraine and record LNG export volumes. At $3.85/MMBtu in 2025, 50 of 91 remaining operators — 55% — continue to operate coal plants that are economically uncompetitive with gas generation on a fuel cost basis alone.
The most important finding is the declining operator count: from 149 in 2008 to 91 in 2025, a 39% reduction. This is the coal fleet retirement happening in real time in the data. The operators that remain tend to have the lowest-cost coal supply chains — Midwestern utilities with mine-mouth plants, long-term supply contracts with Powder River Basin mines, and efficient modern boilers. They represent the hardest cases for gas competition to displace.
The regulatory implication is direct: utilities operating coal plants where the switching threshold has been exceeded should be required to demonstrate why continued coal operation serves ratepayer interests. The fuel cost data from Form 923 makes this analysis available to any commission staff or intervener without any proprietary modeling.
| Utility | St | Coal Cost ($/MMBtu) | Heat Rate (MMBtu/MWh) | Gas Threshold ($/MMBtu) | Gas Price ($/MMBtu) | Status |
|---|
The gas switching threshold is the gas price at which combined cycle gas generation produces electricity at the same cost per MWh as the existing coal plant. It is computed as:
threshold ($/MMBtu) = coal_cost ($/MMBtu) × coal_heat_rate (MMBtu/MWh) ÷ gas_CC_heat_rate (7.0 MMBtu/MWh)
Coal cost is the quantity-weighted average procurement cost from EIA Form 923 Page 5 (fuel types BIT, SUB, LIG, RC, WC). Coal heat rate is the annual volume-weighted average from Form 923 Page 1 (total MMBtu consumed ÷ net MWh generated). The gas combined cycle heat rate of 7.0 MMBtu/MWh is the EIA standard for modern CCGT plants. For 2008–2010, operator-specific heat rates are unavailable (Page 1 not in converted files) — the national average of 10.5 MMBtu/MWh is used as a proxy.
When the annual average gas price exceeds the threshold, gas-fired combined cycle generation is cheaper per MWh than the coal plant's actual procurement cost. This does not mean the utility can immediately switch — it means the fuel cost economics favor gas, which is the standard analysis used in integrated resource plans and coal plant retirement proceedings.
| Year | Value 1 | Value 2 |
|---|---|---|
| 2024 | — | — |
| 2023 | — | — |