Gigawatts Aren’t All Created Equal: Why the EIA’s Capacity Data Misleads Policymakers

The United States is in the midst of a historic shift in how it produces electricity, spurred by tax credits, state mandates, and sweeping federal legislation like the “One Big Beautiful Bill Act.” More than 1,100 new wind and solar projects are in the pipeline, and headlines tout renewable energy’s dominance—projected to make up 80% of new generation capacity through 2035.

But are we building the right kind of capacity?

According to my new issue brief from the National Center for Energy Analytics, the U.S. Energy Information Administration (EIA) is misleading policymakers—not by intent, but by omission. By reporting only, the nameplate capacity of solar and wind projects without adjusting for intermittency, the EIA gives a distorted view of how much reliable energy these resources will actually provide.

Why Nameplate Capacity Isn’t Enough

A gigawatt of solar is not equivalent to a gigawatt of natural gas when it comes to delivering electricity on demand. Solar and wind are intermittent resources—they only generate power when the sun shines or the wind blows. That means additional backup (like batteries or natural gas plants) must be built to compensate for the hours, days, or even weeks when renewable output dips.

The availability of solar and wind is measured by their capacity factors, which measures the percentage of generation relative to 24-7 output. In 2024, solar operated at just 23% of nameplate capacity, and wind at 34%. Compare that to natural gas combined-cycle plants, which averaged nearly 60% and can exceed 90% when run as baseload power.

When you adjust for these differences, natural gas—not renewables—is set to be the dominant source of useful new electricity capacity through 2035.

The Consequences of Flawed Reporting

Utilities, regulators, and lawmakers rely on EIA data to make long-term planning decisions. If that data overstates the contribution of solar and wind, the grid will end up with insufficient capacity to meet peak demand—especially as electrification pushes winter peaks higher.

The EIA’s widely cited “levelized cost” comparisons, which advocates often use to claim that wind and solar are the lowest-cost resources, are also problematic. These estimates don’t reflect geographic variation, intermittency, or the costs of storage and backup needed to deliver consistent power. As a result, they paint an overly rosy picture of renewable economics.

A Better Way to Measure Value

The fix is straightforward. The EIA should:

• Publish derated capacity additions based on average regional capacity factors.

• Include “effective” cost comparisons that account for backup generation and storage.

• Provide more granular, region-specific data to reflect geographic performance differences.

The energy transition isn’t just about building more megawatts—it’s about building the right ones, in the right places, with an honest understanding of what they can deliver.

Until policymakers demand more realistic reporting, we risk building a power system that looks impressive on paper—but can’t deliver when it matters most.

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