Houston-based Citroniq Chemicals has secured its series A funding. Photo via Getty Images

A fresh $12 million round of funding will enable Houston-based Citroniq Chemicals to propel planning, design, and construction of its first decarbonization plant.

An unidentified multinational energy technology company led the series A round, with participation from Houston-based Lummus Technology Ventures and cooperation from the State of Nebraska. The Citroniq plant, which will produce green polypropylene, will be located in Nebraska.

“Lummus’ latest investment in Citroniq builds on this progress and strengthens our partnership, working together to lower carbon emissions in the plastics industry,” Leon de Bruyn, president and CEO of Lummus Technology, says in a news release.

Citroniq is putting together a decarbonization platform designed to annually capture 2 million metric tons of greenhouse gas emissions at each plant. The company plans to invest more than $5 billion into its green polypropylene plants. Polypropylene is a thermoplastic resin commonly used for injection molding.

The series A round “is just the first step in our journey towards building multiple biomanufacturing hubs, boosting the Nebraska bioeconomy by converting local ethanol into valuable bioplastics,” says Kelly Knopp, co-founder and CEO of Citroniq.

Citroniq’s platform for the chemical and plastics industries uses technology and U.S.-produced ethanol to enable low-cost carbon capture. Citroniq’s process permanently sequesters carbon into a useful plastic pellet.

Lummus Technology licenses process technologies for clean fuels, renewables, petrochemicals, polymers, gas processing and supply lifecycle services, catalysts, proprietary equipment, and digital transformation.

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This article originally ran on InnovationMap.

Branch Energy aims to provide customers with clean energy at a lower cost than competitors. Photo via Getty Images

Houston clean energy provider raises $10.8M series A

money moves

A tech-driven retail energy provider based in Houston has secured an oversubscribed series A round of funding.

Branch Energy raised a $10.8 million round led by climate-focused venture capital firm Prelude Ventures with co-investor Zero Infinity Partners, an infrastructure tech-focused firm. The fresh funding will go toward accelerating the company's battery management tech and build out the infrastructure of its field services.

A vertically integrated power provider, Branch Energy aims to provide customers with demand management software and battery storage systems to ensure long-term, stable, and clean energy at a lower cost than competitors.

“Our century-old grid design is not equipped for the complexity of today’s energy needs," Alex Ince-Cushman, Branch Energy co-founder and CEO, says in a news release. “Optimizing distributed energy assets in real-time will play an increasingly important role in managing the grid. We built Branch from the ground up as a technology company, allowing us to deliver value to customers in this new era of distributed energy by reducing costs while improving reliability."

The company chose Texas as its inaugural market based on the stress of the grid in the state, the company says in the release. Since 2021 when Branch Energy launched, it has signed up thousands of customers for its 100 percent clean energy service. The business proposition includes lowering customer's energy bills by 5 to 10 percent.

“The power grid, especially in Texas, requires distributed generation and flexible loads as basic economics drives deployment of more renewable resources,” Tim Woodward, managing partner at Prelude Ventures, adds. “Across the country, we are experiencing a major shift toward a decentralized and decarbonized grid. Branch Energy is bringing value to its customers through deployment of intelligent storage that lowers costs and improves reliability.”

Branch Energy, which is available now in some Texas regions, had previously raised $5.5 million in seed and pre-seed funding, per Crunchbase.

The series A funding will support the deployment of its biochar machines across Texas, Oklahoma, Arkansas, and Louisiana. Photo courtesy of Applied Carbon

Houston agriculture robotics co. raises $21.5M series A to grow climatetech solution

freshly funded

A Houston energy tech startup has raised a $21.5 million series a round of funding to support the advancement of its automated technology that converts field wastes into stable carbon.

Applied Carbon, previously known as Climate Robotics, announced that its fresh round of funding was led by TO VC, with participation from Congruent Ventures, Grantham Foundation, Microsoft Climate Innovation Fund, S2G Ventures, Overture.vc, Wireframe Ventures, Autodesk Foundation, Anglo American, Susquehanna Foundation, US Endowment for Forestry and Communities, TELUS Pollinator Fund for Good, and Elemental Excelerator.

The series A funding will support the deployment of its biochar machines across Texas, Oklahoma, Arkansas, and Louisiana.

"Multiple independent studies indicate that converting crop waste into biochar has the potential to remove gigatons of CO2 from the atmosphere each year, while creating trillions of dollars in value for the world's farmers," Jason Aramburu, co-founder and CEO of Applied Carbon, says in a news release. "However, there is no commercially available technology to convert these wastes at low cost.

"Applied Carbon's patented in-field biochar production system is the first solution that can convert crop waste into biochar at a scale and a cost that makes sense for broad acre farming," he continues.

Applied Carbon rebranded in June shortly after being named a top 20 finalist in XPRIZE's four-year, $100 million global Carbon Removal Competition. The company also was named a semi-finalist and awarded $50,000 from the Department of Energy's Carbon Dioxide Removal Purchase Pilot Prize program in May.

"Up to one-third of excess CO2 that has accumulated in the atmosphere since the start of human civilization has come from humans disturbing soil through agriculture," Joshua Phitoussi, co-founder and managing partner at TO VC, adds. "To reach our net-zero objectives, we need to put that carbon back where it belongs.

"Biochar is unique in its potential to do so at a permanence and price point that are conducive to mass-scale adoption of carbon dioxide removal solutions, while also leaving farmers and consumers better off thanks to better soil health and nutrition," he continues. "Thanks to its technology and business model, Applied Carbon is the only company that turns that potential into reality."

The company's robotic technology works in field, picking up agricultural crop residue following harvesting and converts it into biochar in a single pass. The benefits included increasing soil health, improving agronomic productivity, and reducing lime and fertilizer requirements, while also providing a carbon removal and storage solution.

"We've been looking at the biochar sector for over a decade and Applied Carbon's in-field proposition is incredibly compelling," adds Joshua Posamentier, co-founder and managing partner of Congruent Ventures. "The two most exciting things about this approach are that it profitably swings the agricultural sector from carbon positive to carbon negative and that it can get to world-scale impact, on a meaningful timeline, while saving farmers money."

Houston-based Sage Geosystems announced the first close of $17 million round led by Chesapeake Energy Corp. Photo via sagegeosystems.com

Chesapeake Energy backs Houston geothermal tech co. in $17M series A

fresh funding

A Houston geothermal startup has announced the close of its series A round of funding.

Houston-based Sage Geosystems announced the first close of $17 million round led by Chesapeake Energy Corp. The proceeds aim to fund its first commercial geopressured geothermal system facility, which will be built in Texas in Q4 of 2024. According to the company, the facility will be the first of its kind.

The venture is joined by technology investor Arch Meredith, Helium-3 Ventures and will include support from existing investors Virya, LLC, Nabors Industries Ltd., and Ignis Energy Inc.

“The first close of our Series A funding and our commercial facility are significant milestones in our mission to make geopressured geothermal system technologies a reality,” Cindy Taff, CEO of Sage Geosystems, says in a news release. “The success of our GGS technologies is not only critical to Sage Geosystems becoming post-revenue, but it is an essential step in accelerating the development of this proprietary geothermal baseload approach. This progress would not be possible without the ongoing support from our existing investors, and we look forward to continuing this work with our new investors.”

The 3-megawatt commercial facility will be called EarthStore and will use Sage’s technology that harvests energy from pressurized water from underground. The facility will be able to store energy — for short and long periods of time — and can be paired with intermittent renewable energy sources like wind and solar. It will also be able to provide baseload, dispatchable power, and inertia to the electric grid.

In 2023, Sage Geosystems debuted the EarthStore system in a full-scale commercial pilot project in Texas. The pilot produced 200 kilowatt for more than 18 hours, 1 megawatt for 30 minutes, and generated electricity with Pelton turbines. The system had a water loss of less than 2 percent and a round-trip efficiency (RTE) of 70-75.

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This article originally ran on InnovationMap.

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3 Houston energy companies rank among most innovative startups in Texas

report card

Three Houston companies claimed spots on LexisNexis's 10 Most Innovative Startups in Texas report, with two working in the geothermal energy space.

Sage Geosystems claimed the No. 3 spot on the list, and Fervo Energy followed closely behind at No. 5. Fintech unicorn HighRadius rounded out the list of Houston companies at No. 8.

LexisNexis Intellectual Property Solutions compiled the report. It was based on each company's Patent Asset Index, a proprietary metric from LexisNexis that identifies the strength and value of each company’s patent assets based on factors such as patent quality, geographic scope and size of the portfolio.

Houston tied with Austin, each with three companies represented on the list. Caris Life Sciences, a biotechnology company based in Dallas, claimed the top spot with a Patent Asset Index more than 5 times that of its next competitor, Apptronik, an Austin-based AI-powered humanoid robotics company.

“Texas has always been fertile ground for bold entrepreneurs, and these innovative startups carry that tradition forward with strong businesses based on outstanding patent assets,” Marco Richter, senior director of IP analytics and strategy for LexisNexis Intellectual Property Solutions, said in a release. “These companies have proven their innovation by creating the most valuable patent portfolios in a state that’s known for game-changing inventions and cutting-edge technologies.We are pleased to recognize Texas’ most innovative startups for turning their ideas into patented innovations and look forward to watching them scale, disrupt, and thrive on the foundation they’ve laid today.”

This year's list reflects a range in location and industry. Here's the full list of LexisNexis' 10 Most Innovative Startups in Texas, ranked by patent portfolios.

  1. Caris (Dallas)
  2. Apptronik (Austin)
  3. Sage Geosystems (Houston)
  4. HiddenLayer (Austin)
  5. Fervo Energy (Houston)
  6. Plus One Robotics (San Antonio)
  7. Diligent Robotics (Austin)
  8. HighRadius (Houston)
  9. LTK (Dallas)
  10. Eagle Eye Networks (Austin)

Sage Geosystems has partnered on major geothermal projects with the United States Department of Defense's Defense Innovation Unit, the U.S. Air Force and Meta Platforms. Sage's 3-megawatt commercial EarthStore geothermal energy storage facility in Christine, Texas, was expected to be completed by the end of last year.

Fervo Energy fully contracted its flagship 500 MW geothermal development, Cape Station, this spring. Cape Station is currently one of the world’s largest enhanced geothermal systems (EGS) developments, and the station will begin to deliver electricity to the grid in 2026. The company was recently named North American Company of the Year by research and consulting firm Cleantech Group and came in at No. 6 on Time magazine and Statista’s list of America’s Top GreenTech Companies of 2025. It's now considered a unicorn, meaning its valuation as a private company has surpassed $1 billion.

Meanwhile, HighRadius announced earlier this year that it plans to release a fully autonomous finance platform for the "office of the CFO" by 2027. The company reached unicorn status in 2020.

Tech entrepreneur turned climate investor is on a mission to monetize carbon removal

now streaming

The climate conversation is evolving — fast. It’s no longer just about emissions targets and net-zero commitments. It’s about capital, infrastructure, and execution at industrial scale.

That’s exactly where Yao Huang operates. A seasoned tech entrepreneur turned climate investor, Yao brings sharp clarity to one of the biggest challenges in climate innovation: how do we fund and scale technologies that remove carbon without relying on goodwill or government subsidies?

In this episode of the Energy Tech Startups Podcast, Yao sits down with hosts Jason Ethier and Nada Ahmed for a wide-ranging conversation that redefines how we think about decarbonization. From algae-based photobioreactors that capture CO₂ at the smokestack, to financing models that mirror real estate and infrastructure—not venture capital—Yao lays out a case for why the climate fight will be won or lost on spreadsheets, not slogans.

Her message is as bold as it is practical: this isn’t about saving the planet for the sake of it. It’s about building profitable, resilient systems that scale. And Houston, with its industrial base and project finance expertise, is exactly the place to do it.

The 40-Gigaton Challenge—and a Pandemic Pivot

Yao’s entry into climate wasn’t part of a long-term plan. It was sparked by a quiet moment during the pandemic—and a book.

Reading How to Avoid a Climate Disaster by Bill Gates, she came to two uncomfortable realizations:

  1. The people in power don’t actually have this figured out, and
  2. She would be alive to suffer the consequences.

That insight jolted her out of the traditional tech world and into climate action. She studied at Stanford, surrounded herself with mentors, and began diving into early-stage climate deals. But she quickly realized that most of the solutions she was seeing were still years away from commercialization.

So she narrowed her focus: no R&D moonshots, no science experiments—just deployable solutions that could scale now.

Carbon Optimum: Where Algae Meets Infrastructure

That’s how she found Carbon Optimum, a company using algae photobioreactors to remove CO₂ directly from industrial emissions. Their approach is both elegant and economic:

  • Install algae reactors next to major emitters like coal and cement plants.
  • Feed the algae with flue gas, allowing it to absorb CO₂ in a controlled system.
  • Harvest the algae and convert it into valuable commodities like bio-oils, fertilizer, and food ingredients.

It’s a nature-based solution, enhanced by engineering.
One acre of tanks can capture emissions and generate profit—without subsidies.

“This is one of the few solutions I’ve seen that can scale profitably and quickly,” Yao says. “And we’re not inventing anything new—we’re just doing it better.”

The Real Problem? It’s Capital, Not Carbon

As an investor, Yao is blunt: most climate startups are misaligned with the capital markets.

They’re following a tech startup playbook—built for SaaS, not steel. But building climate infrastructure requires a completely different approach: project finance, blended capital, debt structures, carbon credit integration, and regulatory incentives.

“Climate tech is more like real estate or healthcare than software,” Yao explains. “You don’t raise six rounds of venture. You build a stack—grants, equity, debt, tax credits—and you structure your project like infrastructure.”

It’s not just theory. It’s exactly how Carbon Optimum is expanding—through partnerships, offtake agreements, and real-world deployments. And it’s why she believes many climate startups fail: they don’t speak the language of finance.

Houston’s Role in the Climate Capital Stack

For Yao, Houston isn’t just a backdrop—it’s a strategic asset.

The city’s deep bench of project finance professionals, commodity traders, lawyers, and infrastructure veterans makes it uniquely positioned to lead the deployment phase of climate solutions.

“We’ve been calling it the wrong thing,” she says. “This isn’t just about climate—it’s an energy transition. And Houston knows how to build energy infrastructure at scale.”

Still, she notes, the ecosystem needs to evolve. Less education, more execution. Fewer workshops, more closers.

“Houston could be the epicenter of this movement—if we activate the right people and get the right projects over the line.”

From Carbon Capture to Circular Economies

The potential applications of Carbon Optimum’s algae platform go beyond carbon capture. Because the output—algae biomass—can be converted into:

  • Renewable oil
  • High-efficiency fertilizers (critical in today’s geopolitically fragile supply chains)
  • Food ingredients rich in protein and nutrients
  • Even biochar, a highly stable form of carbon sequestration

It’s scalable, modular, and location-agnostic. In island nations, Yao notes, these systems can offer energy independence by turning waste CO₂ into local energy and fertilizer—without needing to import fuels or food.

“It’s not just emissions reduction. It’s economic sovereignty through circular systems.”

Doing, Not Just Talking

One of Yao’s key takeaways for founders? Don’t waste time. Climate startups don’t have the luxury of trial-and-error cycles stretched over years.

“Founders need to get real about what it takes to scale: talent, capital, storytelling, partnerships. If you’re not ready to do that, maybe you should be a CSO, not a CEO.”

She also points out that founders don’t need to hire everyone—they need to tap the right networks. And in cities like Houston, those networks exist—if you know how to motivate them.

“It takes a different kind of leadership. You’re not just raising money—you’re moving people.”

Why This Episode Matters

This conversation is for anyone who’s serious about scaling real solutions to the climate crisis. Whether you’re a founder navigating capital markets, an investor seeking return and impact, or a policymaker designing the frameworks — Yao Huang offers a grounded, urgent, and actionable perspective.

It’s not about hope. It’s about execution.

Listen to the full episode of the Energy Tech Startups Podcast with Yao Huang:


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Hosted by
Jason Ethier and Nada Ahmed, the Digital Wildcatters’ podcast, Energy Tech Startups, delves into Houston's pivotal role in the energy transition, spotlighting entrepreneurs and industry leaders shaping a low-carbon future.


Rice scientist receives $2 million award for research on 'new type of fuel'

winner, winner

Rice University chemistry professor László Kürti was named as a recipient of the 2025 Ross M. Brown Investigator Award from the California Institute of Technology’s Brown Institute for Basic Sciences.

Kürti is one of eight mid-career faculty members to receive up to $2 million over five years for their research in the physical sciences.

“I’m greatly honored,” Kürti said in a news release. “We will learn a tremendous amount in the next five years and gain a much clearer understanding of the challenges ahead.”

Kürti was selected for the research he’s been developing for six years on a molecule called tetrahedral N4, which studies show can release large amounts of energy on demand. The molecule can also decompose directly into nitrogen gas without producing carbon dioxide or water vapor. Kürti believes N4 can be used as a "new type of fuel for vehicles."

“Eventually, N4 and other stable, neutral polynitrogen cages could be used to power rockets, helping us reach the moon or Mars faster and with heavier payloads,” he added in this release.

The Brown Investigator Awards were founded by entrepreneur and Caltech alumnus Ross M. Brown and established by the Brown Science Foundation in 2020. The organization has recognized 21 scientists over the last five years.

“Midcareer faculty are at a time in their careers when they are poised and prepared to make profound contributions to their fields,” Brown said in the news release. “My continuing hope is that the resources provided by the Brown Investigator Awards will allow them to pursue riskier innovative ideas that extend beyond their existing research efforts and align with new or developing passions, especially during this time of funding uncertainty.”