Houston energy startup closes $17M series A to fund Texas geothermal facility

money moves

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

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," she continues.

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.

From Your Site Articles
This week's roundup of Houston innovators includes Jai Shah of Kahuna, Cindy Taff of Sage Geosystems, and Patrick Flam of Revterra. Photos courtesy

3 Houston innovators to know this week

who's who

Editor's note: Each week, I'm introducing you to three Houston innovators to know — three individuals behind recent innovation and startup news stories in Houston as reported by InnovationMap. Learn more about them and their recent news below by clicking on each article.

Jai Shah, CEO of Kahuna Workforce Solutions

Kahuna CEO Jai Shah shares how he plans on deploying the $21 million his Houston company just raised. Photo courtesy of Kahuna

With a recent $21 million series B funding round set to fuel more growth and expand an impressive client roster, Kahuna Workforce Solutions is riding a big wave into 2024.

CEO Jai Shah tells InnovationMap that the Houston skills management software service company’s Hawaiian name captures their style.

“Kahuna is that kind of expert, competent leader in a tribe or family,” Jai says. “That’s all because we had this concept of really wanting to be providing a very..family-oriented consulting approach. Treat our customers like family, and with respect, love and really just try and deliver on that promise.” Continue reading.

Cindy Taff, CEO of Sage Geosystems

Cindy Taff of Sage Geosystems explains why she's so optimistic about geothermal and her company's technology. Photo courtesy of Sage

Geothermal energy is an integral part of decarbonizing the energy industry, and Sage Geosystems CEO Cindy Taff believes her company's tech has what it takes to lead the way.

Founded in Houston in 2020, Sage Geosystems is focused on two business lines — energy storage and geothermal. In addition to developing these technologies, Taff says Sage has "cracked the code" on both reducing costs and maximizing electricity output. Sage has customers ranging from Nabors, the world’s largest land-based drilling company, and Virya LLC, an investor in climate ventures with high impact of eliminating global greenhouse gas emissions or sequestering CO2. Continue reading.

Patrick Flam, CFO of Revterra

Revterra was selected from among 10 finalists receiving up to $1 million piloting opportunities. Photo via ADNOC

Revterra, which produces novel batteries made from recycled steel, has been awarded a million-dollar piloting opportunity by ADNOC following a global competition. The ADNOC Decarbonization Technology Challenge, in collaboration with AWS, bp, Hub71, and the Net Zero Technology Centre, sought to find emerging climate tech innovations that are ready for scale.

At the event in Dubai, Revterra was selected from among 10 finalists receiving up to $1 million piloting opportunities. In addition to the $1 million, they will gain access to facilities and expertise at the ADNOC Research and Innovation Center in Abu Dhabi.

“We are thrilled to win this opportunity,” Patrick Flam, CFO of Revterra, says in a news release. “At Revterra, we have developed an environmentally friendly battery that doesn’t rely on metals like lithium, nickel, or cobalt.” Continue reading.

Cindy Taff of Sage Geosystems explains why she's so optimistic about geothermal and her company's technology. Photo courtesy of Sage

Houston sustainability startup founder on why geothermal is a 'cornerstone' tech for energy transition

Q&A

Geothermal energy is an integral part of decarbonizing the energy industry, and Sage Geosystems CEO Cindy Taff believes her company's tech has what it takes to lead the way.

Founded in Houston in 2020, Sage Geosystems is focused on two business lines — energy storage and geothermal. In addition to developing these technologies, Taff says Sage has "cracked the code" on both reducing costs and maximizing electricity output. Sage has customers ranging from Nabors, the world’s largest land-based drilling company, and Virya LLC, an investor in climate ventures with high impact of eliminating global greenhouse gas emissions or sequestering CO2

In a Q&A that originally ran on EnergyCapital, she explains why she's so optimistic about geothermal and her company's technology.

EnergyCapital: Why do you believe geothermal has a major role to play in the energy transition?

Cindy Taff: Geothermal energy is not just a contender in the energy transition; it is a cornerstone. The question isn’t if we can drive down the costs to be competitive with wind, solar, and natural gas—it’s when. As renewable credits for solar and wind begin to expire, these industries will face the reality of their “real costs.”

As a 24/7 renewable energy source, it provides a constant and reliable power supply, unlike the intermittent nature of solar and wind. Moreover, the rising costs of lithium-ion batteries, driven by the increasing scarcity of lithium and cobalt, further underscore geothermal’s economic viability.

My extensive experience in both geothermal and the O&G sector is a testament to the synergistic relationship between these industries. The skills honed in O&G are not only transferable—they are essential to advancing geothermal technologies. In summary, the O&G industry can make a huge impact to geothermal by systematically driving down costs while scaling up, which is exactly what we did for unconventional shales.

EC: When it comes to finding partners or investors, what are you looking for? What should potential partners/investors know about Sage?

CT: Our technology is ready to scale today, not five to 10 years into the future. We will deliver our first energy storage power plant in 2024 and our first enhanced geothermal power plant in 2025. We are looking for synergies with investors, such as companies with power market or O&G expertise.

In addition, we seek to partner with others who have local content and relationships in places around the world to enable us to quickly and broadly scale our technologies. Sage's technologies are extremely flexible, in that we can deliver energy storage or enhanced geothermal to the utility grid or behind-the-meter to targeted commercial customers, including a dedicated microgrid (i.e., for the U.S. Air Force). Our technologies can provide electricity to remote locations such as mining operations or to large population centers such as Houston, and everything in between.

EC: What's the biggest challenge Sage is facing as an energy transition startup and how do you plan to tackle it?

CT: A common misunderstanding about Sage is that we only do energy storage or that we only do geothermal. However, we do both and the technologies build on one another. Essentially, our energy storage technologies will allow us to "walk" before we "run" with geothermal. On a related point, at this point in the energy transition, time to commercialization and affordability of new clean technology are the leading factors in terms of climate impact. As the first geothermal company to deliver a cost-effective commercial enhanced geothermal system, we are poised to truly make a meaningful difference.

EC: As a woman in a male-dominated industry tackling a global problem, what's been your biggest lesson learned? What's your advice to fellow energy tech female founders?

CT: In my journey as a woman in the energy tech industry, I’ve been fortunate to focus on the work and the global challenges we’re addressing, rather than on any gender-based obstacles. My biggest lesson learned is that innovation and leadership know no gender. Success is driven by perseverance, vision, and collaboration.

------

This conversation has been edited for brevity and clarity.

The six finalists for the sustainability category for the 2023 Houston Innovation Awards weigh in on their challenges overcome. Photos courtesy

Top Houston-based sustainability startups share their 4 biggest challenges

houston innovation awards

Six Houston-area sustainability startups have been named finalists in the 2023 Houston Innovation Awards, but they didn't achieve this recognition — as well as see success for their businesses — without any obstacles.

The finalists were asked what their biggest challenges have been. From funding to market adoption, the sustainability companies have had to overcome major obstacles to continue to develop their businesses.

The awards program — hosted by InnovationMap, and Houston Exponential — will name its winners on November 8 at the Houston Innovation Awards. The program was established to honor the best and brightest companies and individuals from the city's innovation community. Eighteen energy startups were named as finalists across all categories, but the following responses come from the finalists in the sustainability category specifically.

    Click here to secure your tickets to see who wins.

    1. Securing a commercial pilot

    "As an early-stage clean energy developer, we struggled to convince key suppliers to work on our commercial pilot project. Suppliers were skeptical of our unproven technology and, given limited inventory from COVID, preferred to prioritize larger clients. We overcame this challenge by bringing on our top suppliers as strategic investors. With a long-term equity stake in Fervo, leading oilfield services companies were willing to provide Fervo with needed drilling rigs, frack crews, pumps, and other equipment." — Tim Latimer, founder and CEO of Fervo Energy

    2. Finding funding

    "Securing funding in Houston as a solo cleantech startup founder and an immigrant with no network. Overcome that by adopting a milestone-based fundraising approach and establishing credibility through accelerator/incubator programs." — Anas Al Kassas, CEO and founder of INOVUES

    "The biggest challenge has been finding funding. Most investors are looking towards software development companies as the capital costs are low in case of a risk. Geothermal costs are high, but it is physical technology that needs to be implemented to safety transition the energy grid to reliable, green power." — Cindy Taff, CEO of Sage Geosystems

    3. Market adoption

    "Market adoption by convincing partners and government about WHP as a solution, which is resource-intensive. Making strides by finding the correct contacts to educate." — Janice Tran, CEO and co-founder of Kanin Energy

    "We are creating a brand new financial instrument at the intersection of carbon markets and power markets, both of which are complicated and esoteric. Our biggest challenge has been the cold-start problem associated with launching a new product that has effectively no adoption. We tackled this problem by leading the Energy Storage Solutions Consortium (a group of corporates and battery developers looking for sustainability solutions in the power space), which has opened up access to customers on both sides of our marketplace. We have also leveraged our deep networks within corporate power procurement and energy storage development to talk to key decision-makers at innovative companies with aggressive climate goals to become early adopters of our products and services." — Emma Konet, CTO and co-founder of Tierra Climate

    4. Long scale timelines

    "Scaling and commercializing industrial technologies takes time. We realized this early on and designed the eXERO technology to be scalable from the onset. We developed the technology at the nexus of traditional electrolysis and conventional gas processing, taking the best of both worlds while avoiding their main pitfalls." — Claus Nussgruber, CEO of Utility Global

    ------

    This article originally ran on EnergyCapital.

    Ad Placement 300x100
    Ad Placement 300x600

    CultureMap Emails are Awesome

    Property Showcase

    Houston ranks No. 2 for share of AI talent in professional services

    AI surge

    Houston’s professional and business services sector—think law, accounting, consulting, and engineering firms—grabs one of the industry’s biggest shares of AI talent.

    A report from commercial real estate services giant CBRE ranks Houston No. 2 among the top 50 U.S. and Canadian tech markets for the concentration of AI talent in professional and business services.

    Houston’s share of AI talent in professional and business services stands at 26 percent, the report shows. Washington, D.C., tops the list at 31 percent. At 25 percent, Dallas-Fort Worth claims the No. 3 spot.

    CBRE based the AI ranking on data from the LinkedIn networking platform.

    The company’s researchers tallied 11,709 AI-related tech jobs in Houston. Nationwide, data scientists lead AI-related job growth in the U.S., according to the report.

    “AI software and hardware developers are currently the most sought-after tech talent by employers,” the report says.

    Houston faces AI talent gap

    DoubleTrack, a provider of AI and data consulting, reported in June that Houston faces an AI talent gap.

    “The places where businesses say they will adopt AI over the next six months, well ahead of where they are today, are mostly the same places already short on talent: Miami, Houston, and Denver among the metros, South Dakota and South Carolina among the states,” DoubleTrack said.

    This labor shortage comes amid Houston’s ascent as an AI hub. For instance, a factory being built here by AI chipmaker NVIDIA and electronics manufacturer Foxconn will produce AI supercomputers and infrastructure systems.

    Houston’s place in the sphere of tech talent

    Overall, Houston ranks No. 32 in the CBRE report among the top 50 U.S. and Canadian markets for tech talent. The San Francisco Bay Area claims the top spot, with Austin at No. 5 and DFW at No. 8.

    CBRE relied on 13 metrics to rank tech talent markets, including concentration of tech talent, tech talent pipeline, and research-and-development investments.

    Here are other Houston details from the report:

    • In 2025, Houston’s tech talent workforce numbered 104,080, up 7.3 percent over the past three years.
    • Houston’s average wage for tech talent within the tech industry was $120,216 in 2025, up 13.3 percent over the past three years.

    New pilot program for air taxis, Project Nexus, takes flight in Texas

    Project Nexus

    By 2029, Texas skies could be buzzing with air taxis, much like they are with drones today.

    To kick off the "Project Nexus" pilot program in Texas, U.S. Transportation Secretary Sean Duffy, U.S. Sen. Ted Cruz, and Texas Department of Transportation officials attended an event September 10 at Fort Worth Alliance Airport, which serves as the launchpad for a statewide pilot program that could result in air taxis, self-piloted planes, and vertical take-off-and-landing aircraft permanently buzzing across the skies of Texas.

    It was the first demonstration in Texas of next-generation aircraft under the pilot program; Texas is the sixth state to participate in the program.

    Air taxi service on the radar
    The federal government has teamed up with aviation companies BETA Technologies and Joby Aviation, as well as the Texas Department of Transportation, to develop regional air taxi service in Dallas, Austin, San Antonio, and eventually Houston.

    Roger Venables, Fort Worth’s aviation director, said in January that he foresees regular air taxi service becoming a reality in the next five years.

    On September 12, a Joby-made electric air taxi took a roundtrip flight between Fort Worth Alliance and Dallas Fort Worth International Airport to test flight operations.

    The mission was part of a five-day test involving Fort Worth Alliance and DFW Airport flights, and flights over the Fort Worth Stockyards, Toyota Motor North America’s Plano headquarters, and other sites.

    A new facility at Fort Worth Alliance will be Joby’s long-term home for regional flight operations.

    Building a 'framework' for electric aircraft
    TxDOT said Project Nexus is aimed at creating “a scalable system” to connect urban areas, rural communities, and neighboring states as air mobility technology advances.

    In a TxDOT release, Marc Williams, the agency’s executive director, said the pilot program will “build a framework for how electric aircraft could one day connect people, goods, and communities across the state.”

    Three-phase project will test flight capabilities

    Initial flights in the third-year pilot program won’t carry passengers, according to TxDOT. Instead, the flights will gather data, validate air travel routes, and help improve the safety of air mobility technology.

    The first phase of the U.S. Department of Transportation’s Project Nexus will feature piloted aircraft such as helicopters and fixed-wing planes. CultureMap previously reported Plano-based VertiPorts by Atlantic, which develops takeoff and landing sites for airplane-helicopter hybrids, would be part of Project Nexus.

    The second phase will involve testing airborne medical and cargo logistics. This includes transporting critical medical supplies or donor organs between rural and urban hospitals in the Austin and San Antonio areas.

    In the third and final phase, passengers will fly aboard air taxis across the Texas Triangle. Dallas-Fort Worth, Austin, Houston, and San Antonio anchor the triangle.

    “In Texas, we don’t wait for the future to arrive, we build it,” Cruz said in the TxDOT release. “The Lone Star State is pushing the boundaries by testing the next generation of aircraft through Project Nexus.”

    “These technologies will connect communities, expand access to jobs and services, and strengthen supply chains,” the senator added. “What starts in Texas will help shape the future of aviation throughout the entire country.”

    ---

    This article originally appeared on CultureMap.com.

    Houston-area NASA contractor plans Nasdaq IPO

    going public

    Webster-based NASA contractor Rothe Development Inc. has filed paperwork with the U.S. Securities and Exchange Commission to go public.

    Rothe, a minority- and woman-owned business, hasn’t yet identified how many shares it will sell and how much money its IPO might raise. Rothe plans to offer Class B common stock on the Nasdaq exchange.

    CEO Karen Wheeler-Hall owns all of the Class A shares and would retain majority control after the IPO, according to the SEC filing. The company plans to use $2.4 million of the IPO proceeds so Wheeler-Hall can pay off a loan from the seller for her 2021 acquisition of Rothe.

    From last December to this May, the company raised about $2.1 million in a pre-IPO private placement at $1 per share, the SEC filing shows.

    Rothe runs NASA training lab in Houston

    Founded in 1967, Rothe supplies engineering, technology, operations and technical services to NASA, the U.S. Department of Defense, other federal agencies, commercial space operators, and regulated industries.

    Rothe is likely best known for operating NASA’s Neutral Buoyancy Laboratory in Houston. The lab trains astronauts for spacewalks and simulates space missions. It supports NASA’s International Space Station and Artemis programs.

    Company sees room for growth

    In the SEC filing, Rothe said it operates in several expanding markets driven by rising investments, including space exploration, national security, cybersecurity and digital infrastructure.

    “We believe these market trends create significant opportunities for continued growth across both government and commercial sectors,” the company said.

    Rothe generated nearly $126.4 million in revenue last year, up from $117.3 million the previous year. However, the company swung to a $700,000 operating loss in 2025 versus $1.8 million in operating income in 2024.

    At the end of 2025, Rothe’s workforce comprised 385 employees and 25 subcontractors. The company also works in the cybersecurity, computer engineering, software development, multimedia and communication, and commercial calibration sectors, according to its website.

    View All Listings