Cindy Taff of Sage Geosystems shares her vision for her company and for the future of energy. Photo courtesy of Sage

When Cindy Taff was a vice president at the giant oil and gas company Shell in Houston, her middle schooler Brianna would sometimes look over her shoulder as she worked from home.

“Why are you still working in oil and gas?” her daughter asked more than once. “Is there a future in it? Why aren’t you moving into something clean?”

The words weighed on Taff.

“As a parent you want to give direction, and was I giving her the right direction?” she recalled.

At Shell, Taff was in charge of drilling wells and bringing them into production. She worked on oil and natural gas that's called unconventional in the industry, because the oil or natural gas is difficult to get out of the ground — it doesn't naturally gush out like in movies. It's a term often used for oily shale rock. Taff was somewhat unconventional for the industry, too. Her coworkers used to tease her for driving an efficient hybrid.

“You’re not helping oil and gas prices by driving a Prius," they'd say.

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EDITOR’S NOTE: This is part of an occasional series of personal stories from the energy transition — the change away from a fossil-fuel based world that largely causes climate change.

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Taff wanted Shell to pursue the energy that comes from the Earth's natural heat — geothermal. Her team looked into it, but Shell never greenlit any of those projects, saying it would take too much time to recoup the investment.

When Brianna went to college, she was passionate about energy too, but she wanted to work on renewables. After her sophomore year, in the summer of 2020, she got an internship at a geothermal company — one that in fact had just been launched by Taff's former colleagues at Shell — Sage Geosystems in Houston.

Now it was Taff looking over her daughter's shoulder and asking question as she worked from home during the pandemic.

And Sage executives were talking to Brianna, too. “We could use your mom here," they said. "Can you get her to come work for us?” Brianna recalled recently.

That's how Cindy Taff left her 36-year career at Shell to become chief operating officer at Sage.

“I didn't understand why Shell wasn't pursuing it,” she said about applying the company's drilling expertise to heat energy. "Then I got this great opportunity to pivot from oil and gas and work with these guys that I have the utmost respect for. And also, I wanted to make my daughter proud, quite frankly.”

Brianna Byrd, now 24, is the operations engineer and spokesperson at the company. She's glad her mother, now CEO, left oil and gas.

“Of course I’m biased, she’s my mom, but I don’t think Sage would be where it is without her,” she said.

The United States is a world leader in electricity made from geothermal energy, but this kind of electricity still accounts for less than half a percent of the nation’s total large-scale generation, according to the U.S. Energy Information Administration. In 2023, most geothermal electricity came from California, Nevada, Utah, Hawaii, Oregon, Idaho and New Mexico, where there are reservoirs of steam, or very hot water, close to the surface.

The Energy Department estimates this next generation of geothermal projects, like what Sage is doing, could provide some 90 gigawatts by 2050 — enough to power 65 million homes or more. That hinges on private investment, and on companies like Sage introducing this form of energy to regions where, until now, it’s been thought to be impossible.

How it works

Sage has two main technologies: The first makes electricity out of heat. The company drills wells and fractures hot, dry rock. Then electric pumps push water into those fractures, heating it up, and the hot water gets jettisoned to the surface where it spins a turbine.

But a funny thing happened during testing in Starr County, Texas. In late 2021, the team realized much of their technology could also be used to store energy.

If that works, it could be a big deal. Currently, to store energy at large scale, the United States is adding batteries, mostly lithium-ion type, to solar and wind projects, so they can charge up and send electricity back to the electric grid when the sun is not shining or the wind is not blowing. These batteries typically supply four hours maximum power.

Sage envisions some of its technology placed at solar and wind farms, too. When electricity demand is low, they'll use extra energy from a solar or wind farm to run electric pumps, pumping water into the underground fractures, leaving it there until demand for electricity increases — storing the energy beneath the Earth's surface for hours, days or even weeks.

It's a novel way to use the technology, said Silviu Livescu, lead author on a report looking at the future of geothermal in Texas. Livescu knows Taff and has followed the company's progress.

“It’s the right moment for companies like Sage with a purpose, with a mission and with the technology to show that geothermal indeed is the energy source we need to address climate change,” said Livescu, who co-founded a different geothermal startup in Austin, Texas.

These days, Taff is often out in front, talking with politicians and policymakers about the potential of geothermal. She attended the United Nations COP28 climate talks last year to share her vision for this kind of energy.

Sage has raised $30 million so far and is growing.

It's building a small (3-megawatt), geothermal energy storage system at San Miguel Electric Cooperative, Inc., south of San Antonio this year. It's working with U.S. military facilities in Texas that see geothermal as a way to power their bases securely. Sage recently announced partnerships for heating communities in Bucharest, Romania; clean electricity from geothermal for Meta's data centers, and energy storage and geothermal projects in California.

The company is final-testing a proprietary turbine to more efficiently convert heat to electricity.

Because of her oil and gas background, Taff said she knows geothermal will only be adopted widely if the cost comes down. The mantra at Sage is: It's going to be clean and it's going to be cheap. She's excited to be working in a field she feels is on the cusp of playing a big role in cleaning and stabilizing the electrical grid.

“I’ve never looked back,” she said. “I love what I’m doing and I think it’s going to be transformative.”

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VC firm partners with Rice Nexus to open first global office

strategic partnership

Luxembourg-based venture capital and advisory firm MoreThan Capital (MTC) has established its first global office at the new Rice Nexus in Houston’s Ion District as part of a strategic partnership aimed at fostering entrepreneurship and growing Houston as an innovation hub.

MTC has committed to offering its “time, mentorship, industry expertise and global connections” to Rice Nexus. The state-of-the-art Rice Nexus, which opened earlier this year, aims to support and provide resources for ventures that are looking to scale and have "artificial intelligence (AI) as a central pillar of its innovation strategy," according to a statement from Rice.

“The Rice Nexus is a launchpad for world-changing ideas, and this partnership with MoreThan Capital is a key step in realizing that vision,” Sanjoy Paul, executive director of the Rice Nexus, said in a news release. “By combining Rice’s research and entrepreneurial talent with MTC’s global network and mentorship, we are creating an unparalleled engine for innovation that starts in Houston and reaches the world.”

MoreThan Capital has over 100 limited partners, including senior executives and professional investors, based in more than 35 countries.

“Establishing our first global office at the Rice Nexus within the Ion District is a significant milestone for MoreThan Capital,” Guillermo Ruiz, general partner of MoreThan Capital, said in a news release. “We are dedicated to partnering with top-tier academic institutions like Rice University and aligning with organizations that share our core values of trust, engagement and impact.”

The announcement comes just a few weeks after Rice Nexus announced its partnership with Google Public Sector to launch the new Rice AI Venture Accelerator, or RAVA.

This Houston neighbor was the fastest growing U.S. city in last decade

Booming Burb

It's no secret that Houston's population is growing faster than most other metros in the U.S., but now a surprising Houston-area neighbor has been named the No. 1 fastest-growing suburb nationwide over the last decade: the booming city of Fulshear.

Fulshear led the nation with an astonishing 1,082 percent increase in population from 2014 to 2023, according to a recent growth study by marketplace platform StorageCafe.

Overall, Texas cities dominated StorageCafe's list of the top 10 fastest-growing U.S. cities from 2014 to 2023.

The report said the city had nearly 27,000 residents in 2023, but now the U.S. Census Bureau estimates Fulshear's population has now grown to more than 42,600 people.

"With its blend of a relaxed lifestyle, urban conveniences, top-rated schools and strong job opportunities, Fulshear consistently ranks among the best places to live in Texas," the report's author wrote.

This isn't the first time Fulshear has entered the spotlight for its exploding population: it was the No. 2 fastest-growing U.S. city in 2023, and recently came out on top of GoBankingRates' new study ranking of the fastest-growing affluent suburbs in America for 2025.

Several other Houston-area suburbs also saw major growth over the last decade, including Manvel (No. 24), Katy (No. 82), and Conroe (No. 83).

"Manvel doubled its population between 2014 and 2023, while Katy and Conroe each recorded increases of over 50 percent," the report said. "By contrast, Houston itself grew by just 6 percent, aligning with the average growth rate for large U.S. cities."

The report added that the Houston area's population surge has also led to a high demand for housing, where home values have risen 60 percent over the last 10 years. Home prices in Fulshear stood at more than $521,000 in November 2024, whereas Manvel's home prices were over $431,000 during that same period.

For comparison, the national average price of a home is $354,000.

Katy and Conroe had the most affordable home prices out of the four Houston suburbs in the report, at $347,740 and $318,952, respectively, for November.

StorageCafe says the reasons for population shifts vary greatly, with many people seeking out cities with a more affordable cost of living, or those moving for socioeconomic factors like better employment opportunities.

"Population growth is far from even across the U.S. Some cities are experiencing significant increases, directly driven by steady in-migration, rising immigration and birth rates outpacing death rates," the report said. "But what’s fueling these trends runs deeper — economic and social forces like shifting job markets, the rise of remote and hybrid work and soaring living costs are all reshaping where people choose to live."

Other fast-growing Texas cities
Texas had the greatest number of cities to earn spots in the report's ranking of the 100 fastest-growing U.S. cities over the last decade, with 25 total cities making the cut with the highest growth rates nationwide.

Dallas-Fort Worth had the highest number of fastest-growing Texas suburbs on the list, comprising 11 cities: Celina (No. 2), Melissa (No. 3), Princeton (No. 7), Prosper (No. 8), Fate (No. 9), Anna (No. 14), Midlothian (No. 33), Royse City (No. 43), Forney (No. 45), Little Elm (No. 58), and Frisco (No. 72).

Meanwhile, Austin had five suburbs land on the list: Manor (No. 6), Leander (No. 16), Kyle (No. 53), Hutto (No. 54), and Buda (No. 68).

San Antonio also had five suburbs make the top 100, including Boerne (No. 63), Selma (No. 74), Fair Oaks Ranch (No. 70), New Braunfels (No. 77), and Canyon Lake (No. 99).

The top 10 fastest-growing cities over the last decade are:

  • No. 1 – Fulshear, Texas
  • No. 2 – Woodbridge, Virginia
  • No. 3 – Celina, Texas
  • No. 4 – Davenport, Florida
  • No. 5 – Melissa, Texas
  • No. 6 – Manor, Texas
  • No. 7 – Princeton, Texas
  • No. 8 – Prosper, Texas
  • No. 9 – Fate, Texas
  • No. 10 – Nolensville, Tennessee
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This article originally appeared on our sister site, CultureMap.com.

Houston space tech startups share latest updates on lunar missions and more

space update

Houston-based space tech companies Axiom Space and Intuitive Machines recently shared updates on innovative projects and missions, each set to launch by 2027.

Axiom Space

Axiom Space, developer of the world’s first commercial space station and other space infrastructure, is gearing up to launch two orbital data center nodes to low-earth orbit by the end of 2025.

The Axiom Space nodes will lay the foundation for space-based cloud computing. Axiom says orbital data centers provide cloud-enabled data storage and processing, artificial intelligence, and machine learning directly to satellites, constellations, and other spacecraft in Earth’s orbit. This innovation will reduce reliance on earth-based systems, enhance wireless mesh networks and improve real-time operation of space-borne assets, according to Axiom.

Axiom has been working on the development of orbital data centers since 2022. The two nodes going into space in 2025 will be part of Kepler Communications’ 10-satellite data relay network, which is scheduled to launch by the end of this year. Axiom Space and Kepler Communications have been collaborating since 2023.

Kam Ghaffarian, co-founder, executive chairman, and CEO of Axiom, says his company already has deals in place with buyers of space-based cloud computing services. Orbital data centers “are integral to Axiom Space’s vision of era-defining space infrastructure, unlocking transformational capabilities and economic growth,” he says.

Axiom Space says it will be able to buy additional payloads on Kepler’s network to boost capacity for orbital data centers. The two companies will team up to provide network and orbital data center services to various customers.

Intuitive Machines

Meanwhile, Intuitive Machines, a space exploration, infrastructure and services company, has picked SpaceX’s Falcon 9 rocket to launch its fourth delivery mission to the moon. The launch will include two lunar data relay satellites for NASA.

Intuitive Machines says its fourth lunar delivery mission is scheduled for 2027. The mission will comprise six NASA commercial lunar payloads, including a European Space Agency drill set designed to search for water at the moon’s south pole.

“Lunar surface delivery and data relay satellites are central to our strategy to commercialize the moon,” Intuitive Machines CEO Steve Altemus says.

The first of five lunar data relay satellites will be included in the company’s third delivery mission to the moon. The fourth mission, featuring two more satellites, will be followed by two other satellite-delivery missions.