Houston hypersonic engine company lands $91M to accelerate production

Clean Speed

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.

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Sage Geosystems brings South Texas geothermal plant online

powering up

Houston-based Sage Geosystems, a provider of geothermal power, has begun full operations at its South Texas facility for the San Miguel Electric Cooperative.

Sage says the plant was recently “placed in service,” according to a news release. This means it’s fully built and tested, and ready to generate and supply electricity to the grid.

Since selling its first electricity in Q2 of this year, the facility has been operating for more than four months to evaluate aspects like efficiency and water management. Sage relied on its GeoTwin modeling tool to carry out some of the testing.

The testing demonstrates Sage’s proprietary approach to geothermal power “overcomes one of the industry’s most persistent challenges, high water losses in engineered reservoirs, while delivering the consistent performance required to scale next-generation geothermal,” co-founder and CEO Cindy Taff said in the release.

Sage says the South Texas facility will serve as a model for future projects, including one in Nevada. The Nevada facility will use Sage’s proprietary technology to extract geothermal heat from hot dry rock, creating a reliable, affordable source of carbon-free power.

During the testing period, water losses amounted to less than 10 percent. This low rate indicates most water remains in the system, enabling Sage to capture more usable energy, boost power production and improve the project’s finances, the company says.

“Commercial geothermal isn’t just about creating a reservoir. It’s about creating one whose performance can be engineered, predicted, and consistent,” Lev Ring, the company’s co-founder, president and chief technology officer, said in the release.

Since being founded in 2020, Sage has raised $159 million in outside funding. This includes a more than $97 million Series B round co-led by Ormat Technologies and Carbon Direct Capital.

Two years ago, Sage announced a deal with Meta Platforms, the parent company of Facebook and Instagram, to supply up to 150 megawatts of geothermal power to Meta data centers.

Halliburton Labs adds 3 energy, materials startups to Houston incubator

green team

Three new companies have joined Halliburton Labs, the incubator for early-stage energy and hardtech startups run by Houston energy giant Halliburton.

Halliburton Labs provides the emerging companies with mentorship, industry connections, laboratory access and other resources as they work toward commercialization. The latest companies to join the incubator focus on battery materials, resource recovery and gas separation solutions to address some of the "key bottlenecks in the energy and industrial landscape," according to a news release.

The new members include:

Electroflow, a California-based company that produces lithium iron phosphate (LFP) cathode material from lithium brines through its proprietary process. LFPs are critical components in batteries used in electric vehicles, grid storage systems and industrial electrification, according to Halliburton Labs.
Osmoses, a Cambridge, Massachusetts-based company that has developed a membrane platform to reduce the energy use, cost and emissions associated with gas separations used in natural gas, hydrogen, helium and other industrial applications
SiTration Inc., another Cambridge, Massachusetts-based company that has developed electro-extraction and filtration technologies to recover critical metals like copper directly from mining waste streams more quickly and affordably. Its process has completed successful pilot projects with Tier 1 mining companies in three continents.

"Affordable and reliable molecules are essential building blocks of the energy future. Each company brings a bold, technical solution to a complex industrial challenge. We look forward to helping them scale and deploy their technologies," Andres Cabada, Halliburton Labs managing director, added in the news release.

Halliburton Labs previously added four new members from around the world —Nandina REM, Noon Energy, Proof Energy and Tidal Metals—this spring. Alumni from the incubator include Houston-based companies like NanoTech Materials, which is developing insulation and fireproofing to reduce heat transfer in buildings and outdoor infrastructure; and SolvCor, which develops water additives to improve cooling for data centers and thermal storage.

With the addition of the three new members, the incubator currently supports nine early-stage companies.

Houston companies advance 200MW green ammonia plant in South Texas

coming soon

Two global companies with a major presence in Houston are teaming up on a green ammonia plant in Port of Victoria, Texas.

Topsoe, a Danish company with operations in Houston and Bayport, Texas, has been tapped to provide ammonia synthesis technology for the project being developed by First Ammonia, a New York-based company with offices in Houston and Denmark.

The flagship 200-megawatt plant will use renewable electricity to produce green hydrogen through electrolysis, which will then be combined with nitrogen from a nearby Air Liquide pipeline to make green ammonia, according to First Ammonia. It is expected to serve both U.S. and global markets.

According to First Ammonia, every 100,000 tons of electric ammonia produced avoids approximately 240,000 tons of CO2 emissions compared to fossil ammonia

The Topsoe technology used on site is designed to be able to increase production from 10 percent to 100 percent within 30 minutes, and decrease production at a similar rate, allowing the plant to respond to fluctuations from solar- or wind-based energy sources.

“Topsoe is the world leader in ammonia synthesis, and First Ammonia is delighted to continue our partnership with them in establishing a green ammonia industry in the US and around the world,” Joel Moser, CEO of First Ammonia, said in a news release.

Topsoe has previously signed on to supply its 100-megawatt solid oxide electrolyser (SOEC) to the First Ammonia project. However, the company announced in March that it did not extend the contract after multiple delays.

The First Ammonia project was originally expected to come online by 2027 and to produce 1.1 million tonnes of green ammonia. The project is now expected to reach financial before the end of 2026, with construction slated to begin in 2027 and commercial operations launching by 2029.

“As green ammonia projects move from ambition to execution, operational flexibility becomes increasingly important,” Yassir Ghiyati, chief commercial officer at Topsoe, added in a news release. “We’re proud to support First Ammonia with technology designed to enable efficient and reliable green ammonia production. We look forward to continuing to work with the First Ammonia team to help bring this important U.S project to life.”

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