Houston cleantech company closes $12M seed round

fresh funding

Helix Earth is developing a retrofit technology that has the potential to cut HVAC energy use by up to 50 percent. Photo via Getty Images

Houston-based Helix Earth Technologies has closed a $12 million Seed 2 funding round to scale manufacturing of its energy-efficient commercial HVAC add-on technology.

Veriten, a Houston-based energy investment firm, led the round. Rua Ventures, Carnrite Ventures, Skywriter LLC and Textbook Ventures also participated.

Helix Earth—which was founded based on NASA technology, spun out of Rice University and has been incubated at Greentown Labs—is developing high-efficiency retrofit dehumidification systems that aim to reduce the energy consumption of commercial HVAC units. The company reports that its technology can lead to "healthier indoor air, lower energy bills, reduced building maintenance, and more comfortable spaces for building owners and occupants."

"Building owners are dealing with rising energy costs, uncontrolled humidity, and aging infrastructure with no viable, cost-effective path forward. We are in the field today solving these problems for commercial customers, and this capital puts us on an aggressive path to scale,” Rawand Rasheed, Helix Earth co-founder and CEO, said in a news release.

“The strength of this round reinforces our team's conviction that we can transform innovation-starved sectors with transformational solutions that deliver order-of-magnitude improvements to owners and operators, for both their bottom line and the environment,” Rasheed added.

Maynard Holt, Veriten’s founder and CEO, said that the investment firm is tripling its investment in Helix Earth.

"The team has built breakthrough technology with real applicability across multiple industries,” Holt said in the release. “Their first product will have an immediate and measurable impact on our energy system, and they are already pursuing adjacent innovations to help heavy industries operate more efficiently and with less waste. This is a well-rounded team with a proven track record of strong execution and disciplined capital management.”

Helix Earth also closed a $5.6 million seed funding round in 2024, led by Veriten.

Last year, the company secured a $1.2 million Small Business Innovation Research (SBIR) Phase II grant and won in the Smart Cities, Transportation & Sustainability contest at the 2025 SXSW Pitch Showcase. Rasheed was also named to the Forbes 30 Under 30 Energy and Green Tech list for 2025.

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Texas City ammonia plant acquired by Yara in $1.3 billion deal

Ammonia Acquisition

Yara North America, a subsidiary of Norwegian fertilizer and ammonia producer Yara International, has agreed to buy an ammonia production plant in Texas City for $1.3 billion.

The seller is GCA Holdings, an affiliate of Texas City-based chemical manufacturer Gulf Coast Ammonia, which is owned by private equity firms Lotus Infrastructure Partners and MB Energy.

The Texas City plant, with an eventual annual capacity of 1.3 million metric tons, is expected to start full production by the end of this year. Yara says the ammonia produced by the plant will serve its own fertilizer production system and its key customers.

During a recent call with analysts and investors, Magnus Ankarstrand, executive vice president and CFO of Yara International, said the plant holds the potential to become one of the company’s most profitable plants. The $1.3 billion purchase price, he added, “is a very attractive entry ticket to ammonia production in the U.S. at a very attractive cost.”

The Texas City plant will add to Yara’s holdings in the Lone Star State, as Yara is the majority owner of an ammonia, hydrogen and nitrogen production plant in Freeport.

Construction of the ammonia plant began in 2020, but technical and infrastructure issues delayed the project. On its website, Gulf Coast Ammonia says the plant represented a $600 million investment.

“Gulf Coast Ammonia is a world-class asset that required disciplined execution across development, financing, construction, and commercial structuring,” Philipp Pletka, managing director of Lotus Infrastructure Partners, says in a news release.

Trexlertown, Pennsylvania-based Air Products, which owns and operates the country’s largest hydrogen pipeline network, will continue to supply hydrogen and nitrogen for the plant under a long-term deal with Yara, according to the release.

However, the news comes two days after Yara International announced that it would no longer be purchasing ammonia assets in the Louisiana Clean Energy Complex (LCEC) from Air Products. In a separate release, Yara said it planned to reallocate funds toward "alternative mature U.S. ammonia investment opportunities with more competitive returns."

Houston hypersonic engine company lands $91M to accelerate production

Clean Speed

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.

14 climatech startups join Greentown Houston in first half of 2026

green team

Climatech incubator Greentown Labs reports that 14 startups have joined its Houston community so far this year.

The companies are among 30 new startups to have joined Greentown Houston and Greentown Boston in 2026. Four of the companies are headquartered in Houston.

The startups are working on a range of "hydrogen-powered heavy-duty transport to AI-driven grid interconnection," according to Greentown.

The local startups that joined Greentown Houston include:

Houston-based Focis AI, which transforms industrial laser scans into structured asset intelligence to automatically identify, classify and map components in refineries and plants
Houston-based Iron Lattice, which develops next-generation memory technology for AI and high-performance computing that improves energy efficiency, endurance and scalability while remaining compatible with existing semiconductor manufacturing
Houston-based Orbital Arc, which is developing a new ion engine designed to improve the efficiency and scalability of spacecraft propulsion from low Earth orbit to deep space
Houston-based Sustain Energy LLC, which delivers cleaner, lower-cost fuel to industrial customers in pipeline-absent, underserved markets, cutting their energy costs and emissions with no infrastructure investment on their end

Other startups from around the world joined the Houston incubator in the same time period, including:

Ankara-based AIS Field, which develops robotic, AI-assisted non-destructive inspection systems, including submersible tank and boiler crawlers
San Francisco-based Armada AI, which builds rapidly deployable modular and edge data centers that run on local, stranded, or renewable power
San Francisco-based Armeta, which turns complex engineering drawings and legacy documentation into structured, usable data
Pittsburgh-based Atlas Robotics, which develops a Physical AI platform that powers autonomous material-handling robots and AI-guided forklifts
Ghana-based Cocoa Potash, which transforms high-emissions agricultural waste from cocoa, coconut, and palm-nut into organic potash, fertilizer and renewable energy
Israel-based Criaterra, which produces low-carbon, cement-free building materials
Italy-based ETAK, which manufactures modular reactors that convert solid waste into clean syngas
Kenya-based FelixFusion, which uses its Felix platform to model every grid connection point, including capacity, upgrade costs, and constraints
San Diego-based Gemini Energy, which builds next-generation fuel cells for data-center power
Tokyo-based Hibot, which develops robotic systems for inspecting and maintaining infrastructure in hazardous, hard-to-access environments
Austin-based Sheetak, which designs and manufactures thermoelectric coolers, generators, and assemblies for solid-state cooling and energy harvesting
The Netherlands-based ToPerform, which makes AI-powered, non-intrusive fouling sensors that monitor pipelines around the clock and predict the optimal cleaning time

Another 16 startups joined Greentown's Boston incubator. See the full list of new members here.

More than 100 startups joined Greentown last year, according to an end-of-year reflection shared by Greentown CEO Georgina Campbell Flatter. Read more about them here.

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