LEARN / GLOSSARY
Utility-scale
A power plant with at least one megawatt of generating capacity. The threshold matters because most published generation statistics count only utility-scale plants, which leaves rooftop solar outside the totals.
Definition
EIA classifies a power plant as utility-scale if it has at least one megawatt of generating capacity. Plants below that threshold, overwhelmingly rooftop solar, are estimated separately as small-scale generation rather than counted in the main series.
Measurement noteThe distinction changes headline numbers. In 2025, wind and solar produced 17 percent of utility-scale generation. Adding estimated small-scale solar raises the figure to 19 percent of total net generation. A comparison between a source using one basis and a source using the other is not a comparison, and neither figure is labelled prominently in most coverage.
Why the dictionary version is insufficient
The word suggests ownership or purpose, as though a utility-scale plant were one operated by a utility. It is a size threshold and nothing more. A one megawatt solar array on a warehouse roof crosses it; a smaller array on the same roof does not.
Why it matters for capacity
Small-scale generation is invisible to the series planners and analysts use most, which means it is systematically understated in national mix discussions and overstated when someone quotes the total-generation basis without saying so.
Related terms
Nameplate capacity · Behind-the-meter · Capacity factor