The US Is Sitting On 161 Gigawatts In Underused Wind Farm Capacity

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The dumpster fire on a runaway train that passes for the Office of the President of the United States notwithstanding, hundreds of functioning wind farms continue to occupy the US, spinning out clean kilowatts from their long blades. That includes many older wind farms with outdated blades, rotors, and other equipment. If the oldest of these were repowered with new, more efficient turbines, the domestic wind industry could add another 161 gigawatts in capacity without having to acquire additional land.

The Repowering Difference

Repowering refers to replacing older, inefficient wind turbines with new rotors, blades, or both. New, taller turbine towers can also improve capacity, as can re-configuring turbine layouts. Either way, repowering enables developers to avoid cumbersome and expensive land acquisition and transmission costs, while reducing permitting complications.

In some repowering projects, the makeover is simply intended to extend the working life of the existing wind farm and reduce operating expenses. In others, the turbines are upgraded to increase capacity.  The number of turbines can also be reduced, while conserving or increasing capacity. With fewer turbines, operating costs are reduced, neighbor complaints and wildlife impacts are forestalled, and the land can bee freed up for other purposes (see more repowering background here).

According to the energy industry tracker Cleanview, the US currently has 1,378 utility-scale wind farms in operation for a total capacity of 158.1 gigawatts. Some of these are new — Cleanview counts 25 new farms added last year alone — but many of the sites are older and ripe for repowering.

The Mount Storm wind farm in Grant County, West Virginia, is a good example. Mount Storm commenced operation in 2008 at 264 megawatts. Last year Clearway Energy announced a $735 million repowering project for the site, cutting the number of turbines from 132 to just 78 while adding 71 megawatts in capacity to arrive at a final total of 335 megawatts, all on the same site as before.

Same Wind Farms, More Than Double The Capacity

Repowering is not a one size fits all solution, but it does add more gigawatts to the nation’s grid, more quickly, than building new wind farms from scratch or, for that matter, building new nuclear or fossil fuel power plants.

A group of researchers based at Stanford University took a look at the repowering potential in the US last year. Based on data up through 2024, they concluded that repowering could add a total of 161 gigawatts to existing farms, more than doubling capacity from 153 gigawatts to 314 gigawatts.

“Repowering could allow onshore wind to meet 21%, instead of 10.5%, of 2024 US electricity demand,” the researchers summarized.

The full study was published earlier this year as a research article in the Proceedings of the National Academy of Science under the title, “The potential for onshore wind repowering to hasten the energy transition in the United States.”

“Our findings offer a data-driven foundation for policymakers, industry leaders, and researchers, demonstrating that repowering is a key, yet overlooked, strategy to accelerate the transition to a sustainable energy future in the United States,” the authors emphasize.

“Considering the lifetime of wind turbines in the United States, wind repowering will play a key role for the world’s largest economy and second-largest emitter of greenhouse gases,” they add for good measure.

Wind Farm Repowering: It’s Complicated. But Not As Complicated As Building New Wind Farms.

An earlier effort to assess wind repowering potential in the US shows similar results while taking note of constraints. If you stroll around the re-made website of the US Department of Energy, you’ll find the Office of Critical Minerals and Energy Innovation, which as of this writing continues to post an article titled, “Wind Repowering Helps Set the Stage for Energy Addition.”

The article summarizes findings of a research team spearheaded by the National Renewable Energy Laboratory (now the National Laboratory of the Rockies), published in the Journal Nature in November of 2020 under the title, “Multifaceted drivers for onshore wind energy repowering and their implications for energy transition.”

“Wind energy is anticipated to become a backbone of the future energy system,” the authors emphasized, clearly not anticipating that 77 million US voters would choose to send a convicted felon back into office just a few years later, in 2024, while gifting him a compliant Republican majority in the House and Senate, to boot.

Although the researchers of 2020 did not anticipate that federal policy makers would soon take a wrecking ball to the domestic wind industry, both onshore and off (looking at you, Interior Secretary Doug Burgum), they did expect that constraints on new wind farm development would be rising. “Ageing wind turbine fleets, increasing land-use constraints and rising relevance of societal factors make the deployment of land-based (onshore) wind energy ever more complicated,” they wrote.

“Consequently, repowering is expected to become a rapidly growing point of focus for the wind industry,” they summarized.

The analysis also drew on data from Denmark, where many repowering projects are partly aimed at mollifying community objections and reducing environmental impacts (break added for readability):

We demonstrate that for wind pioneer in Denmark, only 67% of the capacity removed in repowering projects was related to the physical space needed for a new turbine.

Other factors that drive repowering include regulation (for example, noise-related, 8–17%), development principles (for example, aesthetics, 7–20%) and political bargaining (4–13%).

“The recognition of repowering as a negotiated process between host communities and wind developers will probably be critical to unlock the full potential of wind energy in the future,” the research team emphasized again for good measure.

NREL researcher Eric Lantz also added his insights to the CMEI article. He explained that assessments of wind farms with a narrow focus on technology, economic, and regulatory factors misses the impact of social and environmental elements.

“For wind energy to serve as much as one-third to one-half of our electrical energy needs, we need to understand the varying combined and competing factors at play in wind repowering decisions,” Lantz said.

With that context in mind, the 161-gigawatt calculation is not quite on the mark from what is actually achievable. However, it does serve as a reminder that significant, untapped domestic energy resources are near at hand, waiting to be economically tapped even as Trump burdens ratepayers with the expense of keeping old power plants running…oh, never mind Trump. Even with all his bullying and bluster, last year wind contributed far more to the nation’s grid than coal, natural gas, or nuclear energy, and this year promises more of the same.

In February the US Energy Information Agency ran the numbers for 2026 and came up with an estimate of capacity additions for this year highlighted by 43.4 gigawatts of utility-scale solar and 24 gigawatts of storage, with wind registering a respectable 11.8 gigawatts in third place.

Natural gas is far behind at 6.3 gigawatts, while coal gets nary a mention. Just saying…

Photo: Repowering old wind farms with new turbines can extend the useful life of the site, add more capacity, reduce the number of turbines, or all three (cropped; Pyron Wind Farm in Texas, repowered in 2024, courtesy of GE Vernova).