This Texas coal mine will soon be home to a 1.2GW solar farm

Construction is underway on a $1.7 billion solar and battery storage project in Texas that will turn existing coal mining land into a hub of clean energy generation.

Panamint Capital announced last week that it broke ground on the 1.2-gigawatt Big Rooter Power solar farm in Bremond, about halfway between Dallas and Houston. The project will use some of the land and assets from the adjacent Twin Oaks coal-fired power plant and Calvert surface coal mine, both of which will continue operating.

Panamint’s clean energy project will be among the largest in the nation — and, the developer claims, the biggest solar array ever built at a brownfield site in North America.

“We believe deploying new capacity at existing energy sites is the clearest way to benefit communities, ratepayers, and the environment alike,” said Apolka Totth, CEO of Panamint, a Nevada-based investment firm.

The giant installation will further boost Texas’ thriving solar sector, which this year is expected to generate more electricity than coal in the Lone Star State. The renewable resource is helping meet the state’s energy demand from data centers, manufacturing facilities, and rising air-conditioning use amid more frequent and extreme hot weather.

Panamint, which is backed by the private equity firm KKR, launched in 2019 with the goals of squeezing more life out of existing fossil-fuel infrastructure while building lower-emission facilities on the same sites. In 2023, Panamint acquired the 310-MW Twin Oaks coal plant and Calvert mine ​“with the express intention of leveraging the site’s existing characteristics to massively and rapidly expand generating capability at the lowest possible cost,” Totth said by email. 

Work has started on the first phase of the solar farm, a 491-MW section that is set to go online in August 2028. Construction will begin in December on the remaining 658 MW, which could start producing power in August 2029.

The 10,000-acre Big Rooter site will also include 1.6 gigawatt-hours of battery storage and 20 miles of new extra-high-voltage transmission lines. The investment firm says it also has the infrastructure and natural gas access needed to build at least 800 MW of gas-fired generation, either for the grid or customers like data center developers.

“Big Rooter is a landmark project that reflects the scale of investment being made in America’s energy future,” George Hershman, CEO of Solv Energy, said in a news release. The contractor is building the site’s solar array, substation, and transmission infrastructure.

Turning coal mines into clean energy 

Big Rooter’s pairing with active coal operations makes it unique within the nation’s small but growing coal-to-solar subsector, which has mainly focused on putting panels on former mine lands and retired industrial sites.

The largest of these projects is the 186-MW Tilden Solar Project in southern Illinois, followed by the 111-MW Martin County Solar Project in eastern Kentucky, which both went online last year atop abandoned coal mines.

In Louisiana, the 240-MW Dolet Hills Solar Project is now being built on a former coal mine property. And the developer BrightNight is advancing the Starfire installation on remediated mine land in Kentucky.

In 2023, when BrightNight announced the Appalachian project, electric truck startup Rivian signed on as the anchor customer, with a 100-MW power purchase agreement. Starfire was initially envisioned as a roughly 800-MW project, but is now on track for 410 MW, with construction slated for late 2027 and planned operations in 2030.

“Earlier descriptions of a larger project reflected a broader long-term vision for the site, but as development has progressed, BrightNight has focused on the configuration that best aligns with current interconnection, permitting, site, and customer considerations,” a BrightNight spokesperson said by email. ​“We remain very enthusiastic about Starfire and its importance as a major redevelopment project on former coal mining land in Eastern Kentucky.”

Repurposing old mining sites for solar power has an obvious appeal. As opposition breaks out in rural areas over using prime farmland for solar — concerns stoked by Trump administration officials, including U.S. Agriculture Secretary Brooke Rollins — brownfield projects allow developers to sidestep those conversations and put sullied land to use. Doing so has typically proved more complicated and expensive than placing solar panels on flat fields.

The 2021 bipartisan infrastructure law and 2022’s Inflation Reduction Act provided incentives to make it easier to finance clean energy installations on mine lands, while a $500 million Department of Energy program allocated funding for projects on current or former mines.

But last year, the Trump administration and Congress added more hurdles by phasing out tax credits for solar and wind energy, effectively ending the tax bonus for brownfield developments. And the administration scrapped at least one DOE mine-land award, for Mineral Basin Solar Power, as part of its sweeping cancellation of $7.6 billion in clean energy grants in the 16 states that voted for Democrat Kamala Harris in the 2024 presidential election.

“The federal policy landscape for developing clean energy on mines has changed, but the opportunity hasn’t,” said Jessica Wilkinson, the North America renewable energy team lead for The Nature Conservancy, a global nonprofit.

“In many parts of the country, wind and solar are the cheapest forms of energy and are succeeding on economics alone,” she added. ​“And if building on mine lands, brownfields, and landfills has fewer community conflicts, they may be seen as very enticing.” 

The nonprofit and its partners plan to develop 25 solar and battery storage projects on former mine lands that The Nature Conservancy manages in the Cumberland Forest, which spans parts of Kentucky, Tennessee, and Virginia. The first project, the 10-MW Wildcats Solar in Virginia, is expected to break ground this fall and could start delivering power to the grid next year.

Wilkinson noted that despite the federal pullback, states have continued to show support for what her group calls ​“mining the sun” projects. For example, Ohio and Colorado passed laws to incentivize renewable energy development on former industrial sites. And a handful of federal programs continue providing financial support for cleaning up coal mining areas — a crucial step for enabling future solar development.

“Communities still want to see these lands become economic engines again,” Wilkinson said.

Texas project adds solar — and more coal

Panamint, for its part, said it was able to secure clean energy incentives for Big Rooter Power before Trump signed the One Big Beautiful Bill Act on July 4, 2025, repealing large swaths of the Inflation Reduction Act.

“We ordered long-lead time equipment such as transformers and circuit breakers well before last summer’s OBBBA, so we were largely insulated from those impacts,” Totth said.

She noted that Panamint is partnering with U.S. firms First Solar and Nextpower (formerly Nextracker) to procure domestically made solar modules and racks. Big Rooter is also located in an ​“energy community” — the Department of Energy’s term for brownfield sites and areas affected by coal plant and mine closures. For those reasons, the company says it will receive a federal investment tax credit worth 50% of total project costs.

Yet as Panamint begins installing millions of solar panels in Texas, it has no plans to wind down production at the neighboring Twin Oaks coal plant.

“Twin Oaks is an economically competitive unit that provides low-cost reliability to Texas ratepayers, and we see no reason for an early retirement,” Totth said. She added that the company is also investigating both expanding the Calvert mine area and building a terminal facility to rail in coal for continued operations.

As Totth sees it, the new solar array will produce enough carbon-free power to ​“negate” the coal plant’s emissions profile on an annual basis.

It’s an example of the all-of-the-above approach to energy in Texas. Despite the massive amounts of solar, storage, and wind the state has built, it continues to cling to fossil fuels.