ADVERTISEABOUT USSUBMIT A STORYSUBSCRIBETERMS OF USEPRIVACY POLICY
Visit our family of Brands

Houston hypersonic engine co. completes first successful test flight

Taking Off

Venus Aerospace has reached a major milestone. Courtesy photo

Houston-based Venus Aerospace successfully completed the first U.S. flight test of its proprietary engine at a demonstration at Spaceport America in New Mexico.

Venus’ next-generation rotating detonation rocket engine (RDRE) is supported by a $155,908 federal Small Business Innovation Research (SBIR) grant from NASA and aims to enable vehicles to travel four to six times the speed of sound from a conventional runway. The recent flight test was the first of an American-developed engine of its kind.

"With this flight test, Venus Aerospace is transforming a decades-old engineering challenge into an operational reality,” Thomas d'Halluin, managing partner at Airbus Ventures, an investor in Venus, said in a news release. “Getting a rotating detonation engine integrated, launch-ready, and validated under real conditions is no small feat. Venus has shown an extraordinary ability to translate deep technical insight into hardware progress, and we're proud to support their bold approach in their attempt to unlock the hypersonic economy and forge the future of propulsion."

Venus’ RDRE operates through supersonic shockwaves, called detonations, that generate more power with less fuel. It is designed to be affordable and scalable for defense and commercial systems.

The RDRE is also engineered to work with the company's air-breathing detonation ramjet, the VDR2, which helps enable aircraft to take off from a runway and transition to speeds exceeding Mach 6. Venus plans for full-scale propulsion testing and vehicle integration of this system. Venus’ ultimate goal is to develop a Mach 4 reusable passenger aircraft, known as the Stargazer M4.

"This milestone proves our engine works outside the lab, under real flight conditions," Andrew Duggleby, Venus co-founder and chief technology officer, said in the release. "Rotating detonation has been a long-sought gain in performance. Venus' RDRE solved the last but critical steps to harness the theoretical benefits of pressure gain combustion. We've built an engine that not only runs, but runs reliably and efficiently—and that's what makes it scalable. This is the foundation we need that, combined with a ramjet, completes the system from take-off to sustained hypersonic flight."

The hypersonic market is projected to surpass $12 billion by 2030, according to Venus.

"This is the moment we've been working toward for five years," Sassie Duggleby, CEO and co-founder of Venus Aerospace, added. "We've proven that this technology works—not just in simulations or the lab, but in the air. With this milestone, we're one step closer to making high-speed flight accessible, affordable, and sustainable."

---

This article originally appeared on InnovationMap.com.

Sassie Duggleby is on Inc.'s Female Founders 500 list for 2025. Courtesy photo

Co-founder of Houston hypersonic engine co. lands on Inc. 500 list

Ranking It

Five Houston female founders have been recognized by Inc. Magazine for their innovation, including Sassie Duggleby, the CEO and co-founder of groundbreaking space tech and engine company Venus Aerospace.

The women were named to Inc.'s Female Founders 500 list, which features female entrepreneurs based in the U.S. The group attracted approximately $9 billion in 2024 revenue and $10.6 billion in funding, according to Inc.

“Female founders know what struggle is, but they’re also experts of improvisation, adaptability, and creativity. The women featured on this year’s list exemplify these qualities," Diana Ransom, Inc. executive editor said in a release. "Through times of uncertainty, their unwavering dedication and steadfast leadership are not only inspiring but vital to driving progress.”

Venus Aerospace is the Houston-based company that is developing reusable hypersonic technology that it hopes "will revolutionize and redefine the boundaries of aviation, defense, and beyond." The company won the in the Deep Tech Business category in the 2024 Houston Innovation Awards. Duggleby also serves on the Texas Space Commission board of directors.

Duggleby is joined by four other Houston founders:

  • Stephanie Murphy, CEO and executive chairman of Aegis Aerospace, which provides space services, spaceflight product development, and engineering services. Murphy also serves on the Texas Aerospace Research and Space Economy Consortium Executive Committee.
  • Emily Cisek, founder of The Postage, now known as Paige, a comprehensive life planning and succession software platform for families and small businesses. The company won the Female-Owned Business category in the 2023 Houston Innovation Awards.
  • Margo Jordan, founder of adolescent mental health startup Enrichly, which uses AI-driven self-esteem development and behavioral insights to boost student performance.
  • Nina Magon, founder of Nina Magon Studio / Nina Magon Consumer Products, a residential and commercial interior design company.
"While I don't know many of the ladies on this list, I do know they're some of the most tenacious role models in entrepreneurship. I'm beyond honored to be included among them," Duggleby said in a LinkedIn post.
Twenty-eight Texas female founders made this list, including Kendra Scott and Allison Ellsworth, co-founder of Poppi, and many others.

---

A version of this story first appeared on our sister site, InnovationMap.com.

Venus Aerospace is one step closer to high-speed international travel. Photo courtesy Venus Aerospace

Houston startup with unique engine tech reports milestone testing results

high-speed travel

A Houston-headquartered hardtech company that's working on technology to enable hypersonic travel has announced a partnership with NASA to test its tech.

Venus Aerospace has partnered with NASA’s Marshall Space Flight Center in Huntsville, Alabama, on what is reportedly the longest sustained tests of a rotating detonation rocket engine, also known as an RDRE.

“Venus believes strongly in the performance step-change that RDREs bring for both hypersonic and space applications. The partnership with NASA has been key in maturing this new technology.” Andrew Duggleby, CTO and co-founder of Venus Aerospace, says in a news release.

The company's engine injector, which used regeneratively-cooled RDRE architecture, was tested in a "flight-like manner," according to the company. The technology operated successfully for 4 minutes of hotfire testing — a significant improvement, as engine tests of this type last for only 1 to 2 seconds, according to Venus.

"This long-duration hotfire means RDRE’s have retired a major risk area and are able to move into the few remaining steps before a flight demonstration," reads the press release from Venus.

As Venus continues to develop its technology for research, defense, and commercial missions, it will continue to work with NASA, which is also looking into RDRE technology for lunar and martian landers, in-space operations and logistics, and other deep space missions, per the release, because RDREs are more compact, efficient, and versatile than traditional rocket engines.

"Venus has entered into a second-year contract with NASA to provide engine parts for research and development of NASA’s RDRE," the news release continues. "In year two, NASA, with Venus’s support, will test different propellant combinations on hardware, to operate at even higher thrust levels and to demonstrate efficiency gains promised by the detonation engine."

Last summer, Venus added a new investor to its cap table. Andrew Duggleby founded Venus Aerospace with his wife and CEO Sarah "Sassie" Duggleby in 2020, before relocating to the Houston Spaceport in 2021. Last year, Venus raised a $20 million series A round.

———

This article originally ran on InnovationMap.

At last year's awards program, Cemvita Factory's co-founders, Tara and Moji Karimi, accepted the award for the Green Impact Business category. This year, Moji Karimi served as a judge

18 Houston energy startups named finalists for innovation awards program

companies to watch

The 2023 Houston Innovation Awards announced its 52 finalists — a large portion of which are promising energy transition startups.

The awards program — hosted by EnergyCapital's sister site, 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.

The following startups, which all have an energy transition element to their business, received a finalist position in one or two categories.

Click here to secure your tickets to see who wins.

  • ALLY Energy, helping energy companies and climate startups find, develop, and retain great talent, scored two finalist positions — one in the Female-Owned Business category and the other in the Social Impact Business category.
  • Eden Grow Systems, next generation farming technologies, is a finalist in the People's Choice: Startup of the Year category.
  • Feelit Technologies, nanotechnology for preventive maintenance to eliminate leaks, fires and explosions, increase safety and reduce downtime, is a finalist in the Female-Owned Business category and the People's Choice: Startup of the Year category.
  • Fervo Energy, leveraging proven oil and gas drilling technology to deliver 24/7 carbon-free geothermal energy, scored two finalist positions — one in the Sustainability Business category and the other in the People's Choice: Startup of the Year category.
  • FluxWorks, making frictionless gearboxes for missions in any environment, is a finalist in the Hardtech Business category.
  • Helix Earth Technologies, decarbonizing the built environment and heavy industry, is a finalist in the Hardtech Business category.
  • INOVUES, re-energizing building facades through its non-invasive window retrofit innovations, making building smarter, greener, and healthier for a better and sustainable future, was named a finalist in the Sustainability Business category.
  • Kanin Energy, helping heavy industry monetize their waste heat and decarbonize their operations, was named a finalist in the BIPOC-Owned Business and the Sustainability Business categories.
  • Mars Materials, developing a carbon-negative pathway for carbon fiber and acrylamide production using CO2 and biomass as raw materials, is a finalist in the BIPOC-Owned Business category.
  • Molecule, an energy/commodity trading risk management software that provides users with an efficient, reliable, responsive platform for managing trade risk, is a finalist in the Digital Solutions Business category.
  • Rhythm Energy, 100 percent renewable electricity service for residential customers in Texas, is a finalist in the People's Choice: Startup of the Year category.
  • Sage Geosystems, a cost-effective geothermal baseload energy solution company, also innovating underground energy storage solutions, was named a finalist in the Sustainability Business category.
  • Solugen, decarbonizing the chemical industry, is a finalist in the Hardtech Business category.
  • Square Robot, applying robotic technology to eliminate the need to put people into dangerous enclosed spaces and eliminate taking tanks out of service, is a finalist in the Hardtech Business category.
  • Syzygy Plasmonics, a deep decarbonization company that builds chemical reactors designed to use light instead of combustion to produce valuable chemicals like hydrogen and sustainable fuels, is a finalist in the Hardtech Business category.
  • Tierra Climate, decarbonizing the power grid faster by helping grid-scale batteries monetize their environmental benefits and change their operational behavior to abate more carbon, was named a finalist in the Sustainability Business category.
  • Utility Global, a technology company converting a range of waste gases into sustainable hydrogen and syngas, was named a finalist in the Sustainability Business category.
  • Venus Aerospace, a hypersonics company on track to fly reusable hypersonic flight platforms by 2024, is a finalist in the Hardtech Business category.

Additionally, two energy companies were named to the Corporate of the Year category, which honors corporations that supports startups and/or the Houston innovation community. Aramco Ventures and Chevron Technology Ventures are two of the four finalists in this category.

Lastly, Jason Ethier, co-founder of Lambda Catalyzer and host of the Energy Tech Startups podcast, and Kendrick Alridge, senior manager of community at Greentown Labs, scored finalist positions in the Ecosystem Builder category, as individuals who have acted as leaders in developing Houston’s startup ecosystem.

Click here to see the full list of finalists.

Ad Placement 300x100
Ad Placement 300x600

CultureMap Emails are Awesome

Property Showcase

Houston's Rhythm Energy expands nationally with clean power acquisition

power deal

Houston-based Rhythm Energy Inc. has acquired Inspire Clean Energy for an undisclosed amount. The deal allows Rhythm to immediately scale outside of Texas and into the Northeast, Midwest and mid-Atlantic regions, according to a release from the company.

Inspire offers subscription-based renewable electricity plans to customers in Pennsylvania, New York, New Jersey, Massachusetts, Ohio, Delaware, Illinois, Maryland, and Washington, D.C. By combining forces, Rhythm will now be one of the largest independent green-energy retailers in the country.

“Adding Inspire to the Rhythm family gives us the geographic reach to serve millions of new customers with the highly rated customer experience Texans already enjoy,” PJ Popovic, CEO of Rhythm, said in the release. “Together we become one of the largest independent green-energy retailers in the country and can roll out innovations like our PowerShift Time-of-Use plan and device-enabled demand-response programs that put customers fully in control of their energy costs.”

Rhythm was founded by Popovic in 2020 and offers 100 percent renewable energy plans using solar power, wind power and other renewable power sources.

In addition to scaling geographically, the acquisition will "(marry) Rhythm's data-driven technology with Inspire's successful subscription model." Rhythm also plans to upgrade its digital tools and provide more advanced services to help lower clean energy costs, according to the release.

Popovic spoke with EnergyCapital in 2023 about where he thinks renewables fit into Texas’s energy consumption. Read more here.

Fervo Energy lands $200 million in capital for new geothermal project

fresh funding

Houston-based Fervo Energy, a producer of geothermal power, has secured $205.6 million in capital to help finance its geothermal project in southern Utah.

The money will go toward the first and second phases of Cape Station, a geothermal energy plant being developed in Beaver County, Utah. Beaver County is roughly an equal distance between Salt Lake City and Las Vegas.

The $205.6 million in capital came from three sources:

  • $100 million in equity from Breakthrough Energy Catalyst, a Kirkland, Washington-based platform that invests in emissions-reducing projects.
  • $60 million addition to Fervo’s existing loan from Mercuria, a Swiss energy and commodities trader. The revolving loan now totals $100 million.
  • $45.6 million in additional bridge debt financing from XRL-ALC, an affiliate of Irvington, New York-based X-Caliber Rural Capital. X-Caliber is a USDA-approved lender. The initial bridge loan was $100 million.

The first phase of Cape Station will supply 100 megawatts of carbon-free electricity to the power grid starting next year. Another 400 megawatts of capacity is supposed to go online by 2028. Fervo has permission to expand Cape Station’s capacity to as much as 2 gigawatts. On an annual basis, 2 gigawatts can supply enough electricity to power about 1.4 million homes.

“These investments demonstrate what we’ve known all along: Fervo’s combination of technical excellence, commercial readiness, and market opportunity makes us a natural partner for serious energy capital. The confidence our investors have in Fervo and in the Cape asset affirms that next-generation geothermal is ready to play a defining role in America’s energy future,” David Ulrey, Fervo’s CFO, said in a news release.

ExxonMobil tops Fortune 500 list and more Houston energy news to know

Trending News

Editor's note: It's time to look back at the biggest energy transition news for the first half of June 2025. Here are the five most-read EnergyCapital stories from June 1-13:

1. 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). On the Fortune 500 list for 2025, Spring-based ExxonMobil remained the highest-ranked company based in the Houston area as well as in Texas, sitting at No. 8 nationally. Continue reading.

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

Yao Huang is the guest on the latest episode of the Energy Tech Startups Podcast. Courtesy photo

A seasoned tech entrepreneur turned climate investor, Yao Huang 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 for a wide-ranging conversation that redefines how we think about decarbonization. Continue reading.


3. Houston students take home top prizes at DOE wind energy competition

Rice Wind Energy had a strong showing at the DOE's 2025 Collegiate Wind Competition. Photo courtesy Rice University.

The student-led Rice Wind Energy team clinched second place overall at the U.S. Department of Energy’s 2025 Collegiate Wind Competition (CWC), which challenges students nationwide to design and build wind turbines, develop wind energy projects and engage in public outreach to promote renewable energy. Continue reading.

4. Houston biotech company continues to expand in Brazil with new research partner

Cemvita has partnered with Brazilian sustainable research institution REMA. Photo courtesy of Cemvita

Houston biotech company Cemvita has announced a strategic collaboration with Brazilian sustainable research institution REMA. The move aims to promote Cemvita’s platform for evaluating and testing carbon waste streams as feedstocks for producing sustainable oil. Continue reading.

5. 6 Houston energy transition events to attend in June 2025

Meet the newest members of Greentown Labs at Transition on Tap. Photo via Greentown Labs

June has arrived, and with it come more must-attend events in the energy transition sector. Mark your calendar today for these conferences, symposiums, summits, expos, and more. Continue reading.

View All Listings