Allen Best, at his blog Big Pivots, published recently that Colorado hit a milestone of 53% renewable generation:
Colorado achieved an energy and climate milestone during the first quarter of 2026. During those three months, 53% of electricity in Colorado came from renewable sources, up from 43% in 2025, according to an Energy Information Administration report filed in May.
The trouble is that this jubilant announcement of a “majority” renewables grid owes more to a stark drop in coal-fired generation than the wind and solar that was added. Percentages rely on both the numerator — how much wind, solar, and hydropower was generated — as well as the denominator, or how much total generation there was.
The U.S. Energy Information Administration’s Electric Power Monthly net generation by state data, released 6/25/2026, demonstrates this. Renewables’ utility-scale generation rose 15.8 percent year-over-year between the first quarter of 2025 (5,934 GWh) and Q1 2026 (6,872 GWh). However, coal’s generation dropped by 62% between Q1 2025 (4,342 GWh) and Q1 2026 (1,643 GWh). Overall, Colorado’s total in-state generation dropped by 922 GWh in Q1 2026 compared with Q1 2025. Renewables’ share of utility-scale generation in Q1 2026 totals 51.5% — which is less than Mr. Best’s 53%, perhaps because the EIA may have revised its figures between last month’s edition and this one, or Mr. Best may be using an all-sectors basis rather than utility-scale.
Why did coal’s generation fall so precipitously? Xcel Energy’s Comanche Unit 3 has been offline since August 2025 for turbine repairs. If coal-fired generation held at its 2025 level (4,342 GWh) and total generation had increased with renewables on top, the Q1 2026 share would be 42.9%, not 51.5%. That’s a marginal percentage-point improvement from the same time the previous year and is entirely on par with the full-year 2025 generation percentage. That’s the result of Colorado’s largest single-year Q1 renewable addition on record, by the way.
Not to mention that the EIA’s figures are in-state generation, not consumption — so it doesn’t count electricity that the state must import over transmission lines, and it does count electricity that the state is exporting (and ergo not consuming) when there are wind gluts. Total in-state generation has hovered around 56,000 GWh over the past decade while Colorado has grown; the state must import more as dispatchable generation retires, and the percentage of renewables masks what actually powers Colorado homes.
Assuming Comanche Unit 3 returns to service in August 2026 as planned — and there aren’t any good alternatives if Xcel wants to maintain a semblance of reliability — then the EIA’s data will reflect a sudden “decline” in the share of renewables generation in Colorado. It isn’t likely that journalists and bloggers will mark the occasion with the same amount of fanfare.
