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.

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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10+ must-attend Houston energy events happening in Q3 2026

Must-attend meetings

Editor's note: Q3 is here, and with it, a full slate of must-attend events for Houston energy professionals. On the agenda are exciting exhibitions, expos, week-long happenings, and more. Mark your calendars for these top Houston energy transition events taking place July to September 2026, and begin registering today. Please note: this article may be updated to include additional events.

July 15-16: Downstream USA Conference & Exhibition

Now in its 14th year, Reuters Events: Downstream USA 2026 brings together 3,000+ decision‑makers from refining, chemicals, petrochemicals, EPCs, technology providers, and more. Join the industry’s largest and most influential downstream gathering, which features more than 160 exhibition spaces to connect owner-operators and solution providers through interactive, peer-led session formats and onstage discussions.

This event begins July 15 at George R. Brown Convention Center. Register here.

July 24: Chevron Innovation Competition

The University of Houston presents the 5th Annual Chevron Innovation Commercialization Competition, a dynamic event that empowers students to transform cutting-edge energy research into real-world solutions. This event is sponsored by Chevron and coordinated by UH Energy.

The elimination round takes place July 24 at 2 pm. Find details here.

August 17-20: IMAGE '26

Co-hosted by SEG and AAPG, the International Meeting for Applied Geoscience and Energy event (IMAGE '26) is the world’s premier gathering for geoscientists, energy professionals, and industry leaders to connect and innovate. A global audience from all sectors of geosciences and energy come together in Houston to collaborate and network through a comprehensive technical program with more than 1,100 presentations, engaging panel discussions, hands-on workshops and courses, and a unique exhibition experience.

This event begins August 17 at George R. Brown Convention Center. Register here.

August 18-19: AVEVA Day Energy & EPC

AVEVA Day Energy & EPC brings together 400+ leaders and experts from the oil & gas, energy, chemicals, and EPC industries. Attendees will connect with peers facing similar challenges, learn from real customer stories, and discover how companies are accelerating operations with AI and industrial intelligence.

This event begins August 18 at Westin Houston Memorial City. Register here.

August 26-27: Texas Energy Forum 2026

Organized by U.S. Energy Stream, the 2026 conference will focuses on the theme, "AI Runs on Texas Energy: How Texas and Alberta Are Powering the AI Revolution." The forum brings together U.S. Senators, members of Congress, senior government officials, and leaders from the energy, technology, manufacturing, and financial sectors for candid discussions on the energy, infrastructure, and technological advancements required to power the AI revolution and strengthen American competitiveness.

This event begins August 26 at the Petroleum Club of Houston. Register here.

September 13-18: Houston Energy & Climate Week

Houston Energy & Climate Week is a six-day gathering that welcomes an unparalleled selection of global energy leaders and communities to the energy capital of the world for a full slate of events, from tech tours and networking to a climatetech summit and digital symposium.

This event kicks off September 13 and continues for six days. Find details here.

September 14-18 Houston Energy + Climate Startup Week

Launched in 2024, the official Houston Energy and Climate Startup Week returns for its third year, showcasing how Houston is developing and scaling real solutions by meeting growing global energy demand while reducing carbon emissions. Join leading energy and climate venture capital investors, industry leaders, and startups from around the world for this showcase of the most innovative companies and technologies that are transforming the energy industry while driving a sustainable, low-carbon energy future.

This event kicks off September 14 and continues all week. Find details here.

September 20-23: 2026 Geothermal Rising Conference

Geothermal Rising Conference is the industry’s flagship annual conference, reflecting the global nature of the geothermal industry while highlighting the width and breadth of the community. The conference offers technical, policy, and market sessions, educational seminars, tours of geothermal and renewable energy projects, and numerous networking opportunities. An additional expo showcases projects, services, and state-of-the-art technology and equipment for the geothermal community.

This event begins September 20 at Marriott Marquis Houston. Register here.

September 22-23: 2026 API Offshore Safe Lifting Conference & Expo

The 2026 API Offshore Safe Lifting Conference & Expo is your opportunity to see the latest offshore developments while sharing experiences, practices, and even information on real-life incidents. The 2026 program features two full days of technical sessions, regulatory insights, and networking focused on advancing offshore lifting safety, with keynotes, emerging technologies, and multiple networking opportunities.

This event begins September 22 at the Royal Sonesta Houston Galleria. Register here.

September 22-24: Intelligent Asset Management in Energy Summit

The Intelligent Asset Management in Energy Summit is the premier North American event dedicated to helping energy leaders unlock the full potential of their assets through advanced analytics, predictive maintenance, and integrated digital strategies. The 2026 summit will cover how innovative asset management solutions can reduce downtime, optimize performance, and deliver measurable ROI in a rapidly evolving energy landscape.

This event begins September 22 at Norris Conference Center. Register here.

Houston startup secures $5M to turn oilfield wastewater into critical minerals

fresh funding

Houston-based startup Altillion has secured $5 million in seed funding to accelerate the commercialization of its proprietary IRIS and ALIX technologies, which convert oilfield-produced water into valuable minerals.

San Francisco-based EIC Rose Rock and Houston-based Flathead Forge led the round. Altillion says the funding will go toward pilot facilities and commercial deployments as the company looks to scale in the U.S.

“Altillion’s efficient and scalable technologies are needed more than ever to reshape critical mineral recovery and facilitate beneficial use of oilfield brines,” Jay Keener, Altillion’s CEO and co-founder, said in a news release. “We’re uniquely positioned to provide a stable, domestic supply of the critical minerals needed for electronics, batteries, healthcare and national defense technologies. This investment from EIC Rose Rock and Flathead Forge enables us to strategically accelerate this impact and is very timely given the current geopolitical dynamics.”

Altillion's IRIS and ALIX platforms extract minerals like iodine, lithium and copper from oilfield-produced water, geothermal brines and salars. This process allows companies to unlock new sources of revenue while also boosting the domestic critical minerals supply chain. The company announced earlier this summer that it will launch a feasibility project in the Permian Basin and aims to develop a path to commercial-scale implementation in the field.

“We are excited to partner with Altillion to scale and deploy these world-class technologies to access the vast wealth hidden in wastewater,” David Clouse, Managing Director of EIC Rose Rock, added in the release. “With Altillion, we’re expanding our ability to empower the energy industry to domestically source the critical minerals America needs for a robust economy and supply chain.”

Altillion was founded by Keener and COO Scott Buckwald in 2023. Keener previously founded KDH Trading, where Buckwald also serves as COO, according to his LinkedIn page.

Houston's KBR to provide tech for Singapore SAF plant

SAF agreement

Houston engineering and technology contractor KBR has been picked as the technology provider for what’s expected to be Asia's first commercial-scale ethanol-to-jet sustainable aviation fuel (SAF) plant.

The proposed plant on Jurong Island in Singapore is being developed by Keppel Ltd.’s Infrastructure Division and Aster Chemicals and Energy. KBR will provide technology licensing and Front-End Engineering Design (FEED) services based on its PureSAF technology.

The plant has a planned production capacity of up to 100,000 tons of SAF per year. The plant is subject to final investment decisions and regulatory approvals.

“We are looking forward to working with Keppel and Aster on this key project and to support Singapore’s ambition of becoming Asia’s leading SAF hub and advancing the ongoing efforts to decarbonize the country’s aviation ecosystem,” Stuart Bradie, KBR president and CEO, said in a news release.

According to KBR, its PureSAF Technology can process multiple feedstocks like bioethanol, syngas, carbon dioxide and hydrogen and convert them to SAF, diesel and gasoline.

The technology was developed by Swedish Biofuels AB and commercialized by KBR.

“KBR’s PureSAF is a feedstock-flexible, bankable technology that is designed to deliver a 100% drop in jet fuel, ready to power aircraft without blending,” Bradie added in the news release. “We are constantly innovating our SAF solution to make it compatible with feedstock availability in different regions and to enable the aviation industry to transition to low-carbon jet fuel with a cost-optimized approach.

KBR has also entered into a memorandum of intent with Keppel’s Infrastructure Division, which states that the companies will collaborate again on decarbonization efforts across biofuels, plastic recycling, digitalization via AI, and SAF.

KBR announced in October that it would spin off its Mission Technology Solutions business, nicknamed SpinCo. The scaled-down KBR, nicknamed RemainCo, would concentrate solely on sustainability technology and services designed to reduce carbon emissions and support energy transition efforts. SpinCo named its new CEO and CFO earlier this month.