Houston clean energy startup acquired by battery storage company FlexGen

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Houston-based Clean Energy Services will operate as a subsidiary of FlexGen. Photo via flexgen.com

A North Carolina company has acquired Houston-based Clean Energy Services, a provider of services for battery energy storage systems and utility-scale solar, for an undisclosed amount.

The buyer is Durham, North Carolina-based FlexGen Power Systems, a provider of battery energy storage software and services.

Clean Energy Services (CES), whose offices are at the Ion, will operate as a subsidiary of FlexGen. Existing CES customers will continue to receive services from CES without disruption or change, FlexGen says.

“Demand for reliable, high-performance power is accelerating, and customers need partners who can deliver at scale,” Kelcy Pegler, CEO of FlexGen, said in a news release. “The addition of CES strengthens our service platform and reinforces our leadership in energy storage technology.”

Ahmad Atwan and Constantine Triantafyllides co-founded CES in 2022. As a startup, CES had raised $8 million in venture capital, according to PitchBook.

“CES has achieved a market leadership position in battery storage services by focusing on reliable speed of service delivery and optimizing asset performance,” Atwan, the company’s CEO, added the release. “FlexGen and CES have been strong partners for years, and this transaction enables us to deliver more robust solutions across a complementary set of customers and markets.”

CES will continue to operate its remote operations center in Houston for over 1 gigawatt of solar assets and 4.5 gigawatt-hours of battery assets, while FlexGen will maintain its remote operations center in Durham.

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Pattern Energy will now own one of the largest independent clean energy infrastructure platforms in North America. Photo via Getty Images

Pattern Energy expands clean energy portfolio with acquisition of Canadian producer

acquisition closed

Clean energy and transmission infrastructure company Pattern Energy completed the acquisition of Canadian independent power producer Cordelio Power this month.

Pattern Energy, which is headquartered in San Francisco and has major operations in Houston, will now own one of the largest independent clean energy infrastructure platforms in North America, according to a release.

Pattern Energy will add approximately 1,550 megawatts of operating and in-construction assets, including 16 wind, solar and energy storage projects across the United States and Canada, as part of the deal. In addition, they have also acquired the majority of Cordelio’s development pipeline in key U.S. markets and members of Cordelio’s team.

“Closing this transaction marks a significant milestone for Pattern Energy as we continue to scale our platform to meet North America’s growing energy needs,” Hunter Armistead, CEO of Pattern Energy, said in the release. “Cordelio brings a highly complementary portfolio of quality assets and a talented team. Together, we are even better positioned to power the future.”

Currently, Pattern Energy’s portfolio includes wind, solar and energy storage projects in over 40 facilities in North America. Pattern Energy had 12,000 megawatts of operating and in-construction capacity before the deal.

The acquisition was first announced Jan. 6, 2025.

“Pattern and Cordelio share a commitment to responsible development and the communities in which we work,” Chris Hind, CEO of Cordelio Power, said in a news release. “We look forward to joining with Pattern Energy to deliver high-quality projects with expanded product offerings to support customers across more markets.”

Pattern Energy doubled down on its Houston commercial space in 2023, moving the company's development, meteorological, transmission and energy trading teams to a new office in the Montrose Collective. The company's Operations Control Center is also based in Houston.

Its Houston-based development team was assigned to work on Pattern's SunZia Transmission and Wind project in New Mexico and Arizona, expected to be one of the largest clean energy infrastructure projects in U.S. The project is targeting commercial operations this year, according to Pattern Energy's website.

Here are the top Houston energy transition stories of the year. Photo via Getty Images

Top 10 headlines that fueled Houston energy transition news in 2025

Year in Review

Editor's note: As we ring in a new year, we're looking back at the hottest energy transition topics of 2025. Here are the 10 most-read EnergyCapitalHTX stories of 2025, from a Texas energy startup's $200M funding round to a Houston energy storage company's major ERCOT deal:

Texas energy startup closes $200M round to fund first factory in the state

Base Power, founded by Justin Lopas and Zach Dell, closed a $200 million series B and plans to expand in Texas and around the country. Photo courtesy Base Power.

Base Power, an Austin-based startup that provides battery-powered home energy services and just entered the Houston market, raised $200 million in series B funding. The money was raised for construction of Base Power’s first factory in Texas and the national expansion of Base Power’s services. Last year, the startup landed $68 million in a series A funding round.

Houston startup secures $22 million for ERCOT energy storage projects

Houston's GoodPeak is breaking ground on its first energy storage projects. Photo via Getty Images.

Houston-based GoodPeak nailed down $22 million in construction debt financing to help build its first two 10-megawatt battery energy storage project. GoodPeak secured the debt financing from financial services company Pathward and renewable energy lender BridgePeak Energy Capital.

CenterPoint partners with AI and infrastructure companies to boost reliability

CenterPoint has partnered with Atlanta-based Osmose and Australia-based Neara to use AI-powered predictive modeling to inform decisions on restorations and risk. Photo via Getty Images

Houston utilities giant CenterPoint is partnering with companies from Atlanta and Australia to use AI to increase data accuracy and strengthen the power grid. The partnership is part of a collaboration between AI-powered predictive modeling platform company Neara and utility infrastructure asset assessment solutions company Osmose.

ExxonMobil, Rice launch sustainability initiative with first project underway

Under a new agreement, ExxonMobil and Rice University aim to develop “systematic and comprehensive solutions” to support the global energy transition. Photo via Getty Images.

Houston-based ExxonMobil and Rice University announced a master research agreement to collaborate on research initiatives on sustainable energy efforts and solutions. The agreement included multiple projects that were expected to be underway in 2025.

Houston expert: From EVs to F-35s — materials that power our future are in short supply

No critical minerals, no modern economy. Getty images

If you’re reading this on a phone, driving an EV, flying in a plane, or relying on the power grid to keep your lights on, you’re benefiting from critical minerals. These are the building blocks of modern life. Things like copper, lithium, nickel, rare earth elements, and titanium, they’re found in everything from smartphones to solar panels to F-35 fighter jets. Continue reading this guest column from Houston energy expert Scott Nyquist.

Greentown Labs announces newest startups to join Houston climatetech incubator

Five companies have joined Greentown Labs Houston, specializing in various "green" applications, from converting plastic waste into sustainable materials to developing energy-storage solutions. Photo courtesy Greentown Labs.

Greentown Labs added five startups to its Houston community in Q1 of 2025. The companies are among a group of 19 that joined the climatetech incubator, which is co-located in Houston and Boston, in the same time period. The companies that joined the Houston-based lab specialize in a number of "green" applications, from converting plastic waste into sustainable materials to developing energy-storage solutions.

Houston cleantech company expands into China with hydrogen energy pilot

HNO International is partnering with Zhuhai Topower New Energy Co. to deploy its modular SHEP technology in China. Graphic courtesy of HNO

Hydrogen-based clean energy technology company HNO International announced its first foray into the Chinese market this spring. The company, which is building a state-of-the-art hydrogen production and refueling facility in Katy, entered into an agreement with renewable energy company Zhuhai Topower New Energy Co. This initiative includes a pilot deployment of HNOI’s Scalable Hydrogen Energy Platform, or SHEP, in China.

CenterPoint reports progress on grid improvements ahead of 2025 hurricane season

CenterPoint Energy aims to complete its suite of grid resiliency projects before the 2025 hurricane season. Photo via centerpointenergy.com

As part of an ongoing process to make Houston better prepared for climate disasters, CenterPoint Energy announced its mid-year progress update on the second phase of the Greater Houston Resiliency Initiative (GHRI). CenterPoint reported that it had completed 70 percent of its resiliency work, and that all GHRI-related actions were expected to be complete before the official start of the 2025 hurricane season.

Daikin completes solar plant to power massive Houston-area campus

Daikin Industries' new solar power plant at its Waller-area campus will power its central chiller plant and is designed to connect to the campus' electric grid. Photo courtesy Daikin.

Japanese HVAC company Daikin Industries completed a nearly one-megawatt solar power plant at its Daikin Comfort Technologies North America campus southeast of Waller. Daikin said the new plant at its 4.2 million-square-foot Daikin Texas Technology Park will eliminate an estimated 845 metric tons of carbon emissions each year. The park houses the largest HVAC factory in North America.

Houston earns No. 3 spot among cities with most Fortune 500 headquarters

Twenty-six Houston-area companies landed on the latest Fortune 500 list. Photo via Getty Images

Houston maintained its No. 3 status this year among U.S. metro areas with the most Fortune 500 headquarters. Fortune magazine tallied 26 Fortune 500 headquarters in the Houston area, behind only the New York City area (62) and the Chicago area (30).

In January 2025, Constellation Energy Corp. announced plans to acquire Houston's Calpine Corp. Photo via LinkedIn

6 major acquisitions that fueled the Houston energy sector in 2025

2025 In Review

Editor's note: As 2025 comes to a close, we're revisiting the biggest headlines and major milestones of the energy transition sector this year. Here are six major acquisitions that fueled the Houston energy industry in 2025:

Houston-based Calpine Corp. to be acquired in clean energy megadeal

Houston's Calpine Corp. will be acquired by Baltimore-based nuclear power company Constellation Energy Corp. Photo via DOE

In January 2025, Baltimore-based nuclear power company Constellation Energy Corp. and Houston-based Calpine Corp. entered into an agreement where Constellation would acquire Calpine in a cash and stock transaction with an overall net purchase price of $26.6 billion. The deal received final regulatory clearance this month.

Investment giant to acquire TXNM Energy for $11.5 billion

Blackstone Infrastructure, an affiliate of Blackstone Inc., will acquire a major Texas electricity provider. Photo via Shutterstock

In May 2025, Blackstone Infrastructure, an investment giant with $600 million in assets under management, agreed to buy publicly traded TXNM Energy in a debt-and-stock deal valued at $11.5 billion. The deal recently cleared a major regulatory hurdle, but still must be approved by the Public Utility Commission of Texas.

Houston's Rhythm Energy expands nationally with clean power acquisition

PJ Popovic, founder and CEO of Houston-based Rhythm Energy, which has acquired Inspire Clean Energy. Photo courtesy of Rhythm

Houston-based Rhythm Energy Inc. acquired Inspire Clean Energy in June 2025 for an undisclosed amount. The deal allowed Rhythm to immediately scale outside of Texas and into the Northeast, Midwest and mid-Atlantic regions.

Houston American Energy closes acquisition of New York low-carbon fuel co.

Houston American Energy Corp. has acquired Abundia Global Impact Group, which converts plastic and certified biomass waste into high-quality renewable fuels. Photo via Getty Images.

Renewable energy company Houston American Energy Corp. (NYSE: HUSA) acquired Abundia Global Impact Group in July 2025. The acquisition created a combined company focused on converting waste plastics into high-value, drop-in, low-carbon fuels and chemical products.

Chevron gets green light on $53 billion Hess acquisition

With the deal, Chevron gets access to one of the biggest oil finds of the decade. Photo via Chevron

In July 2025, Houston-based Chevron scored a critical ruling in Paris that provided the go-ahead for a $53 billion acquisition of Hess and access to one of the biggest oil finds of the decade. Chevron completed its acquisition of Hess shortly after the ruling from the International Chamber of Commerce in Paris.

Investors close partial acquisition of Phillips 66 subsidiary with growing EV network

Two investment firms have scooped up the majority stake in JET, a subsidiary of Phillips 66 with a rapidly growing EV charging network. Photo via Jet.de Facebook.

In December 2025, Energy Equation Partners, a London-based investment firm focused on clean energy companies, and New York-based Stonepeak completed the acquisition of a 65 percent interest in JET Tankstellen Deutschland GmbH, a subsidiary of Houston oil and gas giant Phillips 66.

A unanimous settlement has been reached in Blackstone's $11.5 billion acquisition of TXNM Energy. Photo via Unsplash.

Blackstone clears major step in acquisition of TXNM Energy

power deal

A settlement has been reached in a regulatory dispute over Blackstone Infrastructure’s pending acquisition of TXNM Energy, the parent company of Texas-New Mexico Power Co. , which provides electricity in the Houston area. The settlement still must be approved by the Public Utility Commission of Texas.

Aside from Public Utility Commission staffers, participants in the settlement include TXNM Energy, Texas cities served by Texas-New Mexico Power, the Texas Office of Public Utility Counsel, Texas Industrial Energy Consumers, Walmart and the Texas Energy Association for Marketers.

Texas-New Mexico Power, based in the Dallas-Fort Worth suburb of Lewisville, supplies electricity to more than 280,000 homes and businesses in Texas. Ten cities are in Texas-New Mexico Power’s Houston-area service territory:

Alvin
Angleton
Brazoria
Dickinson
Friendswood
La Marque
League City
Sweeny
Texas City
West Columbia

Under the terms of the settlement, Texas-New Mexico Power must:

Provide a $45.5 million rate credit to customers over 48 months, once the deal closes
Maintain a seven-member board of directors, including three unaffiliated directors as well as the company’s president and CEO
Embrace “robust” financial safeguards
Keep its headquarters within the utility’s Texas service territory
Avoid involuntary layoffs, as well as reductions of wages or benefits related to for-cause terminations or performance issues

The settlement also calls for Texas-New Mexico Power to retain its $4.2 billion five-year capital spending plan through 2029. The plan will help Texas-New Mexico Power cope with rising demand; peak demand increased about 66 percent from 2020 to 2024.

Citing the capital spending plan in testimony submitted to the Public Utility Commission, Sebastian Sherman, senior managing director of Blackstone Infrastructure, said Texas-New Mexico Power “needs the right support to modernize infrastructure, to strengthen the grid against wildfire and other risks, and to meet surging electricity demand in Texas.”

Blackstone Infrastructure, which has more than $64 billion in assets under management, agreed in August to buy TXNM Energy in a $11.5 billion deal.

Neal Walker, president of Texas-New Mexico Power, says the deal will help his company maintain a reliable, resilient grid, and offer “the financial resources necessary to thrive in this rapidly changing energy environment and meet the unprecedented future growth anticipated across Texas.”

Houston's Calpine Corp. will be acquired by Baltimore-based nuclear power company Constellation Energy Corp. Photo via DOE

Constellation and Calpine's $26B clean energy megadeal clears final regulatory hurdle

big deal

Baltimore-based nuclear power company Constellation Energy Corp. received final regulatory clearance this month to acquire Houston-based Calpine Corp. for a net purchase price of $26.6 billion.

The acquisition has the potential to create America’s “largest clean energy provider,” the companies reported when the deal was first announced in January.

The Department of Justice approved the acquisition contingent on Calpine divesting several assets, including one in the Houston area.

The company agreed to divest the Jack Fusco Energy Center natural gas-fired combined cycle facility in Richmond, Texas; four generating assets in the Mid-Atlantic region; and other natural gas plants in Pennsylvania and Corpus Christi, Texas.

The Federal Energy Regulatory Commission, the Public Utility Commission of Texas and the New York Public Service Commission previously approved the deal. The companies can move toward closing the acquisition once the court finalizes the stipulation and order.

"We are very pleased to reach a settlement that allows us to bring together two magnificent companies to create a new Constellation with unprecedented scale, talent and capability to better serve our customers and communities while building the foundation for America’s next great era of growth and innovation," Joe Dominguez, president and CEO of Constellation, said in a news release. "We thank the Department for its professionalism and tireless work reviewing this transaction through these many months. It’s now time for us to complete the transaction, welcome our new colleagues from Calpine, and together begin our journey to light the way to a brilliant tomorrow for all."

Andrew Novotny, CEO of Calpine, will continue to lead the Calpine business and Constellation's fleet of natural gas, hydro, solar and wind generation, according to the company. He will report to Dominguez and also serve as senior executive vice president of Constellation Power Operations.

Constellation is considered one of the top clean energy producers in the U.S. Earlier this month, the company was approved to receive a $1 billion loan from the Department of Energy's Energy Dominance Financing Program to restart its 835-megawatt nuclear reactor in Pennsylvania known as Crane Clean Energy Center.

"Work to restart the reactor comes at a time of unprecedented electric demand growth from electrification and the new data centers needed to support a growing digital economy and to help America win the AI race," a news release from the company reads. "Crane will support grid stability by delivering reliable, around-the-clock electric supply."

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Texas City ammonia plant acquired by Yara in $1.3 billion deal

Ammonia Acquisition

Yara North America, a subsidiary of Norwegian fertilizer and ammonia producer Yara International, has agreed to buy an ammonia production plant in Texas City for $1.3 billion.

The seller is GCA Holdings, an affiliate of Texas City-based chemical manufacturer Gulf Coast Ammonia, which is owned by private equity firms Lotus Infrastructure Partners and MB Energy.

The Texas City plant, with an eventual annual capacity of 1.3 million metric tons, is expected to start full production by the end of this year. Yara says the ammonia produced by the plant will serve its own fertilizer production system and its key customers.

During a recent call with analysts and investors, Magnus Ankarstrand, executive vice president and CFO of Yara International, said the plant holds the potential to become one of the company’s most profitable plants. The $1.3 billion purchase price, he added, “is a very attractive entry ticket to ammonia production in the U.S. at a very attractive cost.”

The Texas City plant will add to Yara’s holdings in the Lone Star State, as Yara is the majority owner of an ammonia, hydrogen and nitrogen production plant in Freeport.

Construction of the ammonia plant began in 2020, but technical and infrastructure issues delayed the project. On its website, Gulf Coast Ammonia says the plant represented a $600 million investment.

“Gulf Coast Ammonia is a world-class asset that required disciplined execution across development, financing, construction, and commercial structuring,” Philipp Pletka, managing director of Lotus Infrastructure Partners, says in a news release.

Trexlertown, Pennsylvania-based Air Products, which owns and operates the country’s largest hydrogen pipeline network, will continue to supply hydrogen and nitrogen for the plant under a long-term deal with Yara, according to the release.

However, the news comes two days after Yara International announced that it would no longer be purchasing ammonia assets in the Louisiana Clean Energy Complex (LCEC) from Air Products. In a separate release, Yara said it planned to reallocate funds toward "alternative mature U.S. ammonia investment opportunities with more competitive returns."

Houston hypersonic engine company lands $91M to accelerate production

Clean Speed

Houston-based Venus Aerospace has closed a $91 million Series B round and plans to scale the production of its hypersonic engine.

The round was led by Houston-based Mercury Fund with participation from Lockheed Martin Ventures, MESH, PEAK6, Draper Associates, Starboard Star Venture Capital, Green Sands Equity and other investors, according to a news release.

The investment comes about a year after Venus completed the first U.S. flight test of its high-thrust rotating detonation rocket engine (RDRE). The engine is expected to enable vehicles to travel four to six times the speed of sound from a conventional runway and is about 15 percent more efficient than traditional alternatives, according to the company.

Venus Aerospace says the latest round of funding will allow it to move the RDRE from demonstration to deployment and meet customer requirements for the near-term defense and space industries. The company says that the reusable RDRE is designed with a "common propulsion architecture" that can work for multiple industries and mission types.

“This financing marks an important step in moving Venus from breakthrough demonstration to scaled capability,” Sassie Duggleby, co-founder and CEO, said in the news release. “Our customers need propulsion systems that go farther, can be produced reliably and are built on supply chains they can trust. We are advancing that capability with American engineering and manufacturing talent to strengthen U.S. defense, expand space access and support the future of high-speed flight.”

Venus Aerospace raised a $20 million Series A in 2022, led by Wyoming-based Prime Movers Lab. At the time, the company said it would put the funding toward three main technologies: a next-generation rocket engine, aircraft shape and leading-edge cooling system.

The company also picked up an investment from Lockheed Martin Ventures, the investment arm of aerospace and defense contractor Lockheed Martin, in November 2025—in addition to funding from other investors over the years.

“Since our initial investment, Venus has progressed very quickly in its technology development," Chris Moran, vice president and general manager of Lockheed Martin Ventures, added in the release. "Our reinvestment in Venus recognizes Venus’ accomplishments to date and focus on speed to manufacture, cost management and reduction of supply chain constraints. Venus is working effectively to position its propulsion system for the production scale required by defense programs.”

"Venus is exactly the kind of company Houston capital should be backing," Blair Garrou, co-founder and managing partner at Mercury Fund, added in the release. "It combines multiple frontier technologies, domestic manufacturing and clear commercial and national security relevance. We believe this team is positioned to lead an important new chapter in defense and space, and we are proud to support a company building breakthrough technology here in Texas."

Venus Aerospace and Houston clean tech startup Vaulted Deep were also named to the World Economic Forum's Technology Pioneers community earlier this summer.

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This article first appeared on InnovationMap.com.

14 climatech startups join Greentown Houston in first half of 2026

green team

Climatech incubator Greentown Labs reports that 14 startups have joined its Houston community so far this year.

The companies are among 30 new startups to have joined Greentown Houston and Greentown Boston in 2026. Four of the companies are headquartered in Houston.

The startups are working on a range of "hydrogen-powered heavy-duty transport to AI-driven grid interconnection," according to Greentown.

The local startups that joined Greentown Houston include:

Houston-based Focis AI, which transforms industrial laser scans into structured asset intelligence to automatically identify, classify and map components in refineries and plants
Houston-based Iron Lattice, which develops next-generation memory technology for AI and high-performance computing that improves energy efficiency, endurance and scalability while remaining compatible with existing semiconductor manufacturing
Houston-based Orbital Arc, which is developing a new ion engine designed to improve the efficiency and scalability of spacecraft propulsion from low Earth orbit to deep space
Houston-based Sustain Energy LLC, which delivers cleaner, lower-cost fuel to industrial customers in pipeline-absent, underserved markets, cutting their energy costs and emissions with no infrastructure investment on their end

Other startups from around the world joined the Houston incubator in the same time period, including:

Ankara-based AIS Field, which develops robotic, AI-assisted non-destructive inspection systems, including submersible tank and boiler crawlers
San Francisco-based Armada AI, which builds rapidly deployable modular and edge data centers that run on local, stranded, or renewable power
San Francisco-based Armeta, which turns complex engineering drawings and legacy documentation into structured, usable data
Pittsburgh-based Atlas Robotics, which develops a Physical AI platform that powers autonomous material-handling robots and AI-guided forklifts
Ghana-based Cocoa Potash, which transforms high-emissions agricultural waste from cocoa, coconut, and palm-nut into organic potash, fertilizer and renewable energy
Israel-based Criaterra, which produces low-carbon, cement-free building materials
Italy-based ETAK, which manufactures modular reactors that convert solid waste into clean syngas
Kenya-based FelixFusion, which uses its Felix platform to model every grid connection point, including capacity, upgrade costs, and constraints
San Diego-based Gemini Energy, which builds next-generation fuel cells for data-center power
Tokyo-based Hibot, which develops robotic systems for inspecting and maintaining infrastructure in hazardous, hard-to-access environments
Austin-based Sheetak, which designs and manufactures thermoelectric coolers, generators, and assemblies for solid-state cooling and energy harvesting
The Netherlands-based ToPerform, which makes AI-powered, non-intrusive fouling sensors that monitor pipelines around the clock and predict the optimal cleaning time

Another 16 startups joined Greentown's Boston incubator. See the full list of new members here.

More than 100 startups joined Greentown last year, according to an end-of-year reflection shared by Greentown CEO Georgina Campbell Flatter. Read more about them here.

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