Solar surpasses coal to become ERCOT’s third-largest power source in 2025

by the numbers

Solar represented 14 percent of energy supplied to the ERCOT electric grid in 2025. Photo via bp.com

Solar barely eclipsed coal to become the third biggest source of energy generated for the Electric Reliability Council of Texas (ERCOT) in 2025, according to new data.

In 2024, solar represented 10 percent of energy supplied to the ERCOT electric grid. Last year, that number climbed to 14 percent. During the same period, coal’s share remained at 13 percent.

From the largest to smallest share, here’s the breakdown of other ERCOT energy sources in 2025 compared with 2024:

Combined-cycle gas: 33 percent, down from 35 percent in 2024
Wind: 23 percent, down from 24 percent in 2024
Natural gas: 8 percent, down from 9 percent in 2024
Nuclear: 8 percent, unchanged from 2024
Other sources: 1 percent, unchanged from 2024

Combined, solar and wind accounted for 37 percent of ERCOT energy sources.

Looking ahead, solar promises to reign as the star of the ERCOT show:

An ERCOT report released in December 2024 said solar is on track to continue outpacing other energy sources in terms of growth of installed generating capacity, followed by battery energy storage.
In December, ERCOT reported that more than 11,100 megawatts of new generating capacity had been added to its grid since the previous winter. One megawatt of electricity serves about 250 homes in peak-demand periods. Battery energy storage made up 47 percent of the new capacity, with solar in second place at 40 percent.

The mix of ERCOT’s energy is critical to Texas’ growing need for electricity, as ERCOT manages about 90 percent of the electric load for the state, including the Houston metro area. Data centers, AI and population growth are driving heightened demand for electricity.

In the first nine months of 2025, Texas added a nation-leading 7.4 gigawatts of solar capacity, according to a report from data and analytics firm Wood Mackenzie and the Solar Energy Industries Association.

“Remarkable growth in Texas, Indiana, Utah and other states ... shows just how decisively the market is moving toward solar,” says Abigail Ross Hopper, president and CEO of the solar association.

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Time is of the essence in getting power plants online. Getty Images

Big Tech's soaring energy demands making coal-fired power plant sites attractive

Transforming Coal Power

Coal-fired power plants, long an increasingly money-losing proposition in the U.S., are becoming more valuable now that the suddenly strong demand for electricity to run Big Tech's cloud computing and artificial intelligence applications has set off a full-on sprint to find new energy sources.

President Donald Trump — who has pushed for U.S. “energy dominance” in the global market and suggested that coal can help meet surging power demand — is wielding his emergency authority to entice utilities to keep older coal-fired plants online and producing electricity.

While some utilities were already delaying the retirement of coal-fired plants, the scores of coal-fired plants that have been shut down the past couple years — or will be shut down in the next couple years — are the object of growing interest from tech companies, venture capitalists, states and others competing for electricity.

That’s because they have a very attractive quality: high-voltage lines connecting to the electricity grid that they aren’t using anymore and that a new power plant could use.

That ready-to-go connection could enable a new generation of power plants — gas, nuclear, wind, solar or even battery storage — to help meet the demand for new power sources more quickly.

For years, the bureaucratic nightmare around building new high-voltage power lines has ensnared efforts to get permits for such interconnections for new power plants, said John Jacobs, an energy policy analyst for the Washington, D.C.-based Bipartisan Policy Center.

“They are very interested in the potential here. Everyone sort of sees the writing on the wall for the need for transmission infrastructure, the need for clean firm power, the difficulty with siting projects and the value of reusing brownfield sites,” Jacobs said.

Rising power demand, dying coal plants

Coincidentally, the pace of retirements of the nation's aging coal-fired plants had been projected to accelerate at a time when electricity demand is rising for the first time in decades.

The Department of Energy, in a December report, said its strategy for meeting that demand includes re-using coal plants, which have been unable to compete with a flood of cheap natural gas while being burdened with tougher pollution regulations aimed at its comparatively heavy emissions of planet-warming greenhouse gases.

There are federal incentives, as well — such as tax credits and loan guarantees — that encourage the redevelopment of retired coal-fired plants into new energy sources.

Todd Snitchler, president and CEO of the Electric Power Supply Association, which represents independent power plant owners, said he expected Trump's executive orders will mean some coal-fired plants run longer than they would have — but that they are still destined for retirement.

Surging demand means power plants are needed, fast

Time is of the essence in getting power plants online.

Data center developers are reporting a yearlong wait in some areas to connect to the regional electricity grid. Rights-of-way approvals to build power lines can also be difficult to secure, given objections by neighbors who may not want to live near them.

Stephen DeFrank, chairman of the Pennsylvania Public Utility Commission, said he believes rising energy demand has made retiring coal-fired plants far more valuable.

That's especially true now that the operator of the congested mid-Atlantic power grid has re-configured its plans to favor sites like retired coal-fired plants as a shortcut to meet demand, DeFrank said.

“That’s going to make these properties more valuable because now, as long as I’m shovel ready, these power plants have that connection already established, I can go in and convert it to whatever," DeFrank said.

Gas, solar and more at coal power sites

In Pennsylvania, the vast majority of conversions is likely to be natural gas because Pennsylvania sits atop the prolific Marcellus Shale reservoir, DeFrank said.

In states across the South, utilities are replacing retiring or retired coal units with gas. That includes a plant owned by the Tennessee Valley Authority; a Duke Energy project in North Carolina; and a Georgia Power plant.

The high-voltage lines at retired coal plants on the Atlantic Coast in New Jersey and Massachusetts were used to connect offshore wind turbines to electricity grids.

In Alabama, the site of a coal-fired plant, Plant Gorgas, shuttered in 2019, will become home to Alabama Power’s first utility-scale battery energy storage plant.

Texas-based Vistra, meanwhile, is in the process of installing solar panels and energy storage plants at a fleet of retired and still-operating coal-fired plants it owns in Illinois, thanks in part to state subsidies approved there in 2021.

Nuclear might be coming

Nuclear is also getting a hard look.

In Arizona, lawmakers are advancing legislation to make it easier for three utilities there — Arizona Public Service, Salt River Project and Tucson Electric Power — to put advanced nuclear reactors on the sites of retiring coal-fired plants.

At the behest of Indiana's governor, Purdue University studied how the state could attract a new nuclear power industry. In its November report, it estimated that reusing a coal-fired plant site for a new nuclear power plant could reduce project costs by between 7% and 26%.

The Bipartisan Policy Center, in a 2023 study before electricity demand began spiking, estimated that nuclear plants could cut costs from 15% to 35% by building at a retiring coal plant site, compared to building at a new site.

Even building next to the coal plant could cut costs by 10% by utilizing transmission assets, roads and buildings while avoiding some permitting hurdles, the center said.

That interconnection was a major driver for Terrapower when it chose to start construction in Wyoming on a next-generation nuclear power plant next to PacifiCorp’s coal-fired Naughton Power Plant.

Jobs, towns left behind by coal

Kathryn Huff, a former U.S. assistant secretary for nuclear energy who is now an associate professor at the University of Illinois Urbana-Champaign, said the department analyzed how many sites might be suitable to advanced nuclear reactor plants.

A compelling factor is the workers from coal plants who can be trained for work at a nuclear plant, Huff said. Those include electricians, welders and steam turbine maintenance technicians.

In Homer City, the dread of losing its coal-fired plant — it shut down in 2023 after operating for 54 years — existed for years in the hills of western Pennsylvania’s coal country.

“It’s been a rough 20 years here for our area, maybe even longer than that, with the closing of the mines, and this was the final nail, with the closing of the power plant,” said Rob Nymick, Homer City's manager. “It was like, ‘Oh my god, what do we do?’”

That is changing.

The plant's owners in recent weeks demolished the smoke stacks and cooling towers at the Homer City Generating State and announced a $10 billion plan for a natural gas-powered data center campus.

It would be the nation’s third-largest power generator and that has sown some optimism locally.

“Maybe we will get some families moving in, it would help the school district with their enrollment, it would help us with our population,” Nymick said. “We’re a dying town and hopefully maybe we can get a restaurant or two to open up and start thriving again. We’re hoping.”

Energy sources are often categorized as renewable or not, but perhaps a more accurate classification focuses on the type of reaction that converts energy into useful matter. Photo by simpson33/Getty Images

How is energy produced?

ENERGY 101

Many think of the Energy Industry as a dichotomy–old vs. new, renewable vs. nonrenewable, good vs. bad. But like most things, energy comes from an array of sources, and each kind has its own unique benefits and challenges. Understanding the multi-faceted identity of currently available energy sources creates an environment in which new ideas for cleaner and more sustainable energy sourcing can proliferate.

At a high level, energy can be broadly categorized by the process of extracting and converting it into a useful form.

Energy Produced from Chemical Reaction

Energy derived from coal, crude oil, natural gas, and biomass is primarily produced as a result of bonds breaking during a chemical reaction. When heated, burned, or fermented, organic matter releases energy, which is converted into mechanical or electrical energy.

These sources can be stored, distributed, and shared relatively easily and do not have to be converted immediately for power consumption. However, the resulting chemical reaction produces environmentally harmful waste products.

Though the processes to extract these organic sources of energy have been refined for many years to achieve reliable and cheap energy, they can be risky and are perceived as invasive to mother nature.

According to the 2022 bp Statistical Review of World Energy, approximately 50% of the world’s energy consumption comes from petroleum and natural gas; another 25% from coal. Though there was a small decline in demand for oil from 2019 to 2021, the overall demand for fossil fuels remained unchanged during the same time frame, mostly due to the increase in natural gas and coal consumption.

Energy Produced from Mechanical Reaction

Energy captured from the earth’s heat or the movement of wind and water results from the mechanical processes enabled by the turning of turbines in source-rich environments. These turbines spin to produce electricity inside a generator.

Solar energy does not require the use of a generator but produces electricity due to the release of electrons from the semiconducting materials found on a solar panel. The electricity produced by geothermal, wind, solar, and hydropower is then converted from direct current to alternating current electricity.

Electricity is most useful for immediate consumption, as storage requires the use of batteries–a process that turns electrical energy into chemical energy that can then be accessed in much the same way that coal, crude oil, natural gas, and biomass produce energy.

Energy Produced from a Combination of Reactions

Hydrogen energy comes from a unique blend of both electrical and chemical energy processes. Despite hydrogen being the most abundant element on earth, it is rarely found on its own, requiring a two-step process to extract and convert energy into a usable form. Hydrogen is primarily produced as a by-product of fossil fuels, with its own set of emissions challenges related to separating the hydrogen from the hydrocarbons.

Many use electrolysis to separate hydrogen from other elements before performing a chemical reaction to create electrical energy inside of a contained fuel cell. The electrolysis process is certainly a more environmentally-friendly solution, but there are still great risks with hydrogen energy–it is highly flammable, and its general energy output is less than that of other electricity-generating methods.

Energy Produced from Nuclear Reaction

Finally, energy originating from the splitting of an atom’s nucleus, mostly through nuclear fission, is yet another way to produce energy. A large volume of heat is released when an atom is bombarded by neutrons in a nuclear power plant, which is then converted to electrical energy.

This process also produces a particularly sensitive by-product known as radiation, and with it, radioactive waste. The proper handling of radiation and radioactive waste is of utmost concern, as its effects can be incredibly damaging to the environment surrounding a nuclear power plant.

Nuclear fission produces minimal carbon, so nuclear energy is oft considered environmentally safe–as long as strict protocols are followed to ensure proper storage and disposal of radiation and radioactive waste.

Nuclear to Mechanical to Chemical?

Interestingly enough, the Earth’s heat comes from the decay of radioactive materials in the Earth’s core, loosely linking nuclear power production back to geothermal energy production.

It’s also clear the conversion of energy into electricity is the cleanest option for the environment, yet adequate infrastructure remains limited in supply and accessibility. If not consumed immediately as electricity, energy is thus converted into a chemical form for the convenience of storage and distribution it provides.

Perhaps the expertise and talent of Houstonians serving the flourishing academic and industrial sectors of energy development will soon resolve many of our current energy challenges by exploring further the circular dynamic of the energy environment. Be sure to check out our Events Page to find the networking event that best serves your interest in the Energy Transition.

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Lindsey Ferrell is a contributing writer to EnergyCapitalHTX and founder of Guerrella & Co.

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EV surge could shutter 40 refineries by 2040, Wood Mackenzie report warns

ev outlook

The rise of electric vehicles could spell trouble for Houston’s oil and gas sector, a new report suggests. But the oil and gas industry stands to benefit from potential sluggishness in U.S. adoption of EVs.

If worldwide EV adoption rises as expected, global oil demand could fall by five million barrels per day by 2040, accelerating the closure of about 40 oil refineries, says the report, published by energy research and consulting firm Wood Mackenzie. The firm’s North American hub is in Houston.

Those closures might spell trouble for refinery operators with a sizable Houston-area presence, including BP, ExxonMobil, Marathon, Saudi Aramco, and Valero. In 2025, the five companies collectively earned roughly $33 billion from downstream operations, including refineries. One caveat: Each company assigns a different definition to “downstream.”

Refineries in Organization for Economic Co-operation and Development (OECD) countries, including the U.S. but excluding Middle Eastern heavyweights, “are most at risk due to their high energy costs and carbon prices,” the Wood Mackenzie report says.

On the flip side, an abundant U.S. oil supply means American drivers have less of an incentive to switch from traditional cars to electric vehicles, despite stubbornly high fuel prices, according to the report.

Wood Mackenzie predicts EVs will account for 20 percent of the U.S. personal and commercial vehicle fleet in 2040, up from three percent in 2025. That compares with a global forecast of 25 percent in 2040, up from 4 percent last year.

Another U.S. roadblock to EV adoption cited in the report: the country’s relative lack of advanced battery manufacturing.

“Without advanced battery technologies, the U.S. auto sector is at risk of ceding its home market to non-Chinese EVs and falling behind competitors internationally,” the report says.

Furthermore, according to the report, Chinese investment in EV manufacturing in the U.S. probably will remain a no-go and tariffs on Chinese EV imports likely won’t be lifted, even if Democrats resurrected EV incentives following a White House win in 2028.

“Competition among EV manufacturers in international markets will only intensify,” the report notes. “Companies that can offer competitive products in high-growth markets will be best positioned for long-term success.”

Houston’s data center capacity set to grow 80%, report says

data findings

Houston stands to benefit from constraints dogging data center markets elsewhere in Texas, a new report indicates. This comes against the backdrop of Texas surpassing Virginia as the country’s top state for data centers — and amid deepening opposition to these facilities.

The report, published by commercial real estate services provider JLL, foresees Houston continuing to gain traction in data center development as occupants seek “scalable alternatives” to Texas markets experiencing supply-and-demand imbalances.

The Houston area currently hosts data centers with 287 megawatts of capacity, well below capacity levels in the Dallas-Fort Worth, Austin-San Antonio and West Texas markets.

However, the region is witnessing a spike in capacity, with 390 megawatts of capacity under construction, according to the report. Counting newly built data centers, Houston would be home to 677 megawatts of data center capacity, an 80 percent increase from the current inventory, the report says.

Developers target West Houston for large-scale data centers

Developers increasingly are evaluating West Houston and surrounding areas for large-scale campuses capable of supporting behind-the-meter power, according to the report. Data center development in the region is likely to remain concentrated in those areas, where power is readily accessible and flood risks are lower, the report adds.

The report notes that Houston is evolving from a traditionally enterprise-focused co-location market for data centers into a “credible large-scale growth market,” buoyed by rising interest in hyperscale facilities and increased development activity.

Corporate, energy and healthcare users are still active in Houston’s data center market, the report says, with cloud computing and technology tenants making inroads. The Houston market absorbed 25 megawatts of data center capacity in the first half of this year.

Texas crowned No. 1 state market for data center capacity

The growth of Houston’s data center sector is occurring in tandem with Texas’ ascent as a data center market. The report shows Texas now boasts 26 gigawatts of existing and under-construction capacity, followed by Virginia at 13 gigawatts.

JLL declares that “Texas has cemented its position as the state for data centers.”

The “frontier” markets of West Texas, the Carolinas, Louisiana, and Ohio account for 77 percent of all capacity being developed nationwide, according to the report.

As evidence of Texas’ heightened stature in the data center sector, commercial real estate services provider Cushman & Wakefield recently ranked Dallas as the world’s No. 1 primary data center market, while Austin-San Antonio led the list of second-tier markets and West Texas topped the third-tier ranking.

These rankings underscore “Texas’ growing importance as a large-scale AI infrastructure hub,” Cushman & Wakefield says.

Opposition to new data centers in Texas grows

While businesses see the value of adding data centers in Texas, the state’s data center boom is rattling residents and politicians alike.

A recent University of Houston survey finds that although 85 percent of Houston-area residents use AI—a key driver of data center growth—nearly 63 percent oppose construction of a data center within a mile of their home. Experts estimate 6.5 gigawatts of capacity, or roughly one-fifth of the total U.S. pipeline, will join the Texas power grid by 2030, with Houston serving as a main hub.

A poll taken recently by the University of Texas/Texas Politics Project yielded similar results: 56 percent of Texans oppose development of data centers in their community.

“Texas’ grid is already facing pressure from population growth, extreme weather and rising industrial demand,” UH researcher Soran Mohtadi says. “When residents say they are concerned about data centers, they’re mostly referring to grid reliability and affordability.”

Data center backlash prompts action by politicians

Responding to Texans’ concerns over power and water consumption, Gov. Greg Abbott recently imposed a moratorium on new data centers in the state to allow time for regulatory agencies to assess the projects’ impact. Meanwhile, some state lawmakers are calling for a crackdown on data center development.

Last month, a state legislative committee chaired by Sen. Joan Huffman, a Houston Republican, held a hearing on the effects of state sales tax exemptions given to data centers. The cost of these exemptions has climbed from an estimated $14.6 million in 2014-15 to a projected $3.3 billion in 2028-29, according to law firm Holland & Knight.

Two backers of massive data centers in Texas, social media giant Meta Platforms and AI powerhouse OpenAI, agreed this week to comply with Abbott’s recently issued standards regarding data center projects—and more have followed suit.

Dan Diorio, executive vice president of state policy and government affairs for the industry-backed Data Center Coalition, fears backlash against data centers may curb economic growth in Texas.

“I worry that communities that put moratoriums ultimately create too much uncertainty and unpredictability, and what that ultimately means is that those communities may shut themselves off to data center development but also may shut themselves off to broader economic development,” Diorio told Fox 7 News in Austin.

Texas battery startup hits $13 billion valuation & more top energy news

Trending News

Editor's note: Summer is sizzling in the energy transition sector, with a big investment for Base Power and the acquisition of Houston-based Zupt. Plus, an Alabama-based renewables company relocates to Houston. Below are the five most-read EnergyCapitalHTX stories published between July 30-August 13, 2026:

1. Texas battery startup Base Power hits $13B valuation with $1B raise

Base Power, an Austin-based residential power provider with a Houston office, has raised $1 billion in a Series D round, bringing the startup’s valuation to $13 billion. Ribbit, Addition, Valor Equity Partners, and JPMorganChase’s Strategic Investment Group led the round, with participation from Altimeter, D1 Capital Partners, Sands Capital, Coatue, Layer Global, and Energy Impact Partners. Existing investors also added to the round, including Thrive Capital, a16z, Lightspeed, Trust Ventures, and CapitalG. Base Power, which provides residential battery backup systems that automatically turn on during outages and sells electricity to homeowners, says the funding will go toward hiring more people and expanding nationally. Continue reading.

2. Houston subsea firm Zupt acquired in offshore tech deal

Houston-based Zupt LLC, a provider of advanced metrology, inspection, and engineering services for offshore energy and renewable projects, has been acquired by Columbus, Ohio-based Rosenxt Holding USA for an undisclosed amount. Rosenxt says the deal, which closed July 21, represents another step in its long-term strategy to build a portfolio of technology and engineering capabilities for the subsea market in the energy sector. Continue reading.

3. Alabama-based renewable fuels company to move HQ to Houston

An Alabama-based clean tech company is moving its headquarters to Houston. Alléo Energy announced that it will move its headquarters from Bay Minette, Alabama, to Houston's Ion District. The company develops carbon-negative fuels and renewable commodities through its conversion technology that turns wood waste and cellulosic feedstocks into high-energy, high-yield syngas. Continue reading.

4. Houston geothermal startup adds former BP, Calpine execs to C-suite

XGS Energy, a Houston-based developer of geothermal power systems, has added several energy industry veterans to its C-suite this summer. The company named Al Vickers as its new chief operating officer earlier this month. Vickers will replace Ghazal Izadi in the role, as she moves into the chief growth officer position. Vickers previously served as CEO of bp's U.S. Low Carbon Energy business and most recently was COO of Houston-based Grid United, which develops next-generation transmission infrastructure. Continue reading.

5. Woodlands-based Lancium teams up on West Texas data center campus

The Woodlands-based Lancium Technologies, which designs, develops, and manages gigawatt-scale data center campuses, has teamed up with Denver-based data center builder and operator Crusoe Energy Systems on a new grid-connected campus more than 100 miles east of Wichita Falls. Construction on the 1-gigawatt Childress County campus, being built for an unidentified tech company, is expected to start in Q3 of this year. Continue reading.

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