Venus Aerospace is propelling forward. Courtesy photo

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.

Two Houston startups have been named World Economic Forum Technology Pioneers. Photo via LinkedIn

Houston startups named to World Economic Forum cohort for carbon removal, clean technologies

top honor

Two Houston-based startups have been selected to join the World Economic Forum's Technology Pioneers community.

The two-year program aims to help mission-driven, early-stage start-ups scale their innovations through multi-stakeholder initiatives, co-creating partnerships and other gatherings for community members. One-hundred startups are selected each year from around the globe, this year hailing from 23 countries and working in AI, energy, space, biotech markets and more.

Cleantech startup Vaulted Deep was one of 11 energy and climate companies to be named to the cohort. Julia Reichelstein and Omar Abou-Sayed founded the company in 2023. Its technology injects excess organic waste underground to remove carbon dioxide from the atmosphere.

Last year, Vaulted Deep inked a 12-year deal with Microsoft to remove up to 4.9 million metric tons of carbon dioxide from the environment.

The startup has earned several accolades in recent years, including a No. 3 spot on Fast Company’s list of the World’s Most Innovative Companies of 2026. It was also recently named to market intelligence and advisory firm Cleantech Group's annual Global Cleantech 100 list for a second year in a row.

"Waste management is one of the world's great invisible infrastructure systems ... The need for new infrastructure is growing as disposal challenges become more complex and regulations evolve. Vaulted is building the first new disposal pathway for organic waste in decades by putting it deep underground, permanently," the company shared in a LinkedIn post. "This year, we're joining the World Economic Forum's 2026 Tech Pioneers alongside innovators working on the many interconnected challenges shaping our future."

Houston-based Venus Aerospace was also selected to join the cohort, along with six other spacetech companies. The company was founded in 2020 by Sassie and Andrew Duggleby.

The startup specializes in next-generation rocket engine propulsion as a cleaner alternative to traditional combustion engines. The company's rotating detonation rocket engine (RDRE) burns fuel more efficiently and completed a successful high-thrust test flight last year. Venus says it’s the only company in the world that makes a flight-proven, high-thrust RDRE with a “clear path to scaled production.”

"Frontier technologies matter most when they expand what people, industries, and nations can do," Sassie Duggleby, co-founder and CEO of Venus, said in a news release. "For Venus, RDRE does not just represent a more efficient engine. It is a foundation for faster movement, more capable space systems, and new forms of connectivity across the planet. Being named a Technology Pioneer validates the potential of this technology to help shape a future where distance is less limiting."

Venus Aerospace has reached a major milestone. Courtesy photo

Houston hypersonic engine co. completes first successful test flight

Taking Off

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."

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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.

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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.

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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.

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Houston company lands first deal from new Blackstone energy transition fund

M&A activity

Asset manager Blackstone has agreed to buy Houston-based Dresser Utility Solutions from Connecticut private equity firm First Reserve for an undisclosed amount. First Reserve has a major presence in Houston.

The deal represents the first investment from Blackstone Energy Transition Partners V.

“Blackstone’s deep resources and experience in the utility sector make them an ideal partner as we continue to invest in innovation, expand our product portfolio, and deliver value for our customers,” Dresser CEO David Evans said in a news release.

Founded in 1880, Dresser provides metering technology, digital instrumentation and software, pressure and flow controls, and infrastructure repair products for gas and water utilities and industrial customers. The company employs about 850 people worldwide.

“As demands on the energy grid continue to grow, Dresser plays a critical role as a trusted partner to utilities managing essential infrastructure. The company’s products are foundational to the safe and reliable operation of gas and water networks, and its reputation for quality has helped build longstanding customer relationships,” David Foley, global head of Blackstone Energy Transition Partners, and JP Munfa, senior managing director, said in the release.

Blackstone Energy Transition Partners has invested more than $28 billion across the energy transition sector. New York-based Blackstone closed Blackstone Energy Transition Partners Fund IV at $5.6 billion in February 2025. Blackstone Energy Transition Partners Fund III closed in 2020 for $4.4 million, according to Pitchbook.

Other notable energy transition investments from Blackstone funds include Salt Lake City-based Energy Exemplar, French electronics manufacturing company Sediver, Plano-based Westwood Professional Services and others.

Two years ago, Dresser secured a $335 million credit facility from funds managed by asset manager Blue Owl Capital. At the time, Dresser said the money would go toward capital expenses, acquisitions and corporate needs.

This is the second notable investment Blackstone has made in a Houston-based energy company in recent months. In May, Blackstone and energy heavyweight Halliburton made a $1 billion equity investment in Houston power generation startup VoltaGrid, which provides behind-the-meter mobile power generation equipment for data centers, microgrids and industrial customers.

Houston cleantech startup closes $17M round to tap into hot geothermal sector

fresh funding

Houston-area startup Hephae Energy Technology Corp. has closed a $17.8 million Series A financing round to commercialize its geothermal technology.

The round was co-led by Pennsylvania-based Susquehanna Sustainable Investments, which invests in early-stage climatech companies, and Copenhagen-based Underground Ventures, which focuses on geothermal energy startups. Alfa8, Baruch Future Ventures, Centaurus Capital LP, Elemental Impact, Exa Ventures, Future Ventures, Grantham Foundation for the Protection of the Environment, New System Ventures and True North Institute joined the round, along with existing Houston-based investor Nabors Industries. Hyphae reports in a news release that the Series A round brings the company's total capital raised to $24.7 million.

Hephae develops ultra-high-temperature downhole sensing, measurement, communications and control systems that can withstand the heat of geothermal sites, which are hotter and deeper than traditional oil and gas reservoirs. The company's Pandora210 system can operate at up to 400 degrees Fahrenheit.

Hephae reports that it plans to use the new funding to commercialize its Pandora210 tool and to launch research and development into systems that can withstand temperatures of up to 570 degrees Fahrenheit. Houston-based Fervo Energy, for instance, recently tapped its hottest geothermal well to date in western Utah, showing temperatures above 555 degrees Fahrenheit.

"Commercial deployment represents a major milestone in our mission to scalable, always-on, emission-free power globally, with a world-class team to tackle this problem," Steve Krase, CEO of Hephae Energy Technology, said in the release." This investment enables Hephae to transition from development to scale, delivering the ultra-high temperature drilling technologies needed to support the rapid growth of the geothermal industry in the US and international markets."

Hephae has been collaborating with Fervo Energy in the field. The company told the Houston Business JournalHouston Business Journal this spring that it expected its Pandora210 technology to be deployed at its Utah sites.

“Fervo is encouraged by the early progress of our collaboration with Hephae, whose novel high-temperature innovations have the potential to contribute positively to EGS economics, unlock higher-energy geothermal resources, and further cement the competitiveness of next-generation geothermal power," Elliot Howard, director of drilling and completions at Fervo, added in the release.

As the geothermal industry continues to scale, Hephae says it aims for its technology to help companies "unlock hotter, deeper resources that result in lower produced energy costs."

The Spring-based startup was founded in 2020 by CEO Steve Krase and CTO John Clegg. Krase previously launched Navigate Energy Services, which was acquired by Nabors in 2013. Clegg is also an industry veteran and has held numerous leadership positions at energy companies, including Weatherford, NOV, Schlumberger and others.