These Houston startups raised more than a quarter billion dollars last month alone. Photo courtesy Venus Aerospace

Houston startups carried the fundraising momentum of Q1 and Q2 into July with several significant seed funding, Series A and Series B rounds.

From geothermal leaders to medtech innovators, these six Houston companies raised more than a quarter billion dollars last month alone, according to reporting by InnovationMap and our sister site, EnergyCapitalHTX.com.

Did we miss a funding round? Let us know by emailing innoeditor@innovationmap.com.

Altillion

Houston-based startup Altillion has secured $5 million in seed funding to accelerate the commercialization of its proprietary IRIS and ALIX technologies, which convert oilfield-produced water into valuable minerals, the company reported earlier this month.

San Francisco-based EIC Rose Rock and Houston-based Flathead Forge led the round. Altillion says the funding will go toward pilot facilities and commercial deployments as the company looks to scale in the U.S. Continue reading.

Buildforce

The U.S. is grappling with a current shortage of 50,000 electricians, according to the National Electrical Contractors Association. Photo via Unsplash

Houston-based Buildforce, which provides a tech-enabled staff platform geared toward electricians and electrical contractors, closed a $10 million Series A round led by Houston’s Saepio Capital last month.

Other investors in the round include Blue Heron Capital, Revolution’s Rise of the Rest Seed Fund, S3 Ventures and Chicago Ventures.

Buildforce says the funding will help fuel its national expansion and further development of its technology.

The startup, founded in 2019, connects electricians with electrical contractors for commercial and industrial construction projects. Continue reading.

Hephae Energy Technology Corp.

The company develops ultra-high-temperature tools to withstand the heat of geothermal reservoirs. Photo via hephaeet.com

Houston-area startup Hephae Energy Technology Corp. closed a $17.8 million Series A financing round last month 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. Hephae reports in a news release that the Series A round brings the company's total capital raised to $24.7 million. Continue reading.

TYBR Health

The company's B3 GEL System is designed to protect tendons, ligaments and muscles while they heal from orthopedic surgery. Photo via Unsplash

Houston-based healthtech startup TYBR Health has raised a $30 million Series A round to scale its B3 GEL System, which helps protect tendons from scarring after surgery, the company announced last month.

The round was led by Minneapolis-based Vensana Capital and Cleveland-based Mutual Capital Partners, with participation from Denver-based Neovate Capital Partners and existing investors, according to a news release from the company.

TYBR Health said it plans to use the funding to broaden the B3 GEL System's clinical applications, expand commercialization and conduct studies to evaluate its ability to protect tissue and improve healing outcomes. Continue reading.

Venus Aerospace 

Venus Aerospace has secured funding from Mercury Fund, Lockheed Martin Ventures and others. Photo courtesy Venus Aerospace

Houston-based Venus Aerospace closed a $91 million Series B round last month 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. Continue reading.

Quaise Energy

A rendering of a Quaise Energy geothermal plant. Rendering via quaise.com

Houston-based Quaise Energy, a producer of utility-scale geothermal power, closed $134 million in a Series B round last month to advance its “superhot” geothermal power plant.

Climate-focused San Francisco-based investment firm Prelude Ventures led the round, with participation from JERA Co., Japan’s largest power generation company, and Idemitsu Kosan, one of Japan’s largest energy companies. Nearly all existing investors, including cleantech-focused investment firm Safar Partners, participated in the round.

The startup expects more equity and debt deals to close “imminently.” Quaise has raised $230 million since its founding in 2018. Continue reading.

Fervo Energy's recent IPO is a signal of where Houston's venture ecosystem stands—and where it can go. Photo via Pexels

Experts: Houston's VC ecosystem has set the foundation — now we need scale

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Fervo Energy went public earlier this summer. The Houston geothermal company priced its IPO at $27 per share, raised $1.89 billion, and opened the next morning at a market capitalization north of $10 billion. By most measures, it is the largest venture-backed cleantech IPO in history and an unambiguous win for Houston. It’s also a useful moment to look at where Houston's venture ecosystem stands and where it can go. The highlight: Houston's venture ecosystem has real foundations and, with increased company formation activity, can grow into the scale our city's ambitions deserve.

A Houston energy story in the national recovery

The recent uptick in Houston venture activity follows national trends. U.S. venture deal count contracted roughly 22 percent from its 2021 peak through 2024 before rebounding to about 16,700 rounds in 2025. Houston's 23 percent increase in VC funding from 2023 to 2024 is part of a national recovery of comparable magnitude over the same time window.

The energy sector is where Houston exhibits unique trends—and where the story turns clearly positive. (Houston's strong health and space sectors deserve their own separate consideration.) By deal count, energy-related rounds have accounted for 15 to 20 percent of Houston activity, roughly consistent over the past few years.

By capital, energy's share surged from about 14 percent in 2023 to over 60 percent in 2025, driven by a small number of large Houston-headquartered rounds, primarily in geothermal and related technologies. Fervo is the obvious anchor, but Sage Geosystems, Quaise Energy, Zeta Energy, Vaulted Deep, Applied Carbon and Mariana Minerals have all closed meaningful rounds. Houston is concentrated and accelerating as an energy capital market, an invaluable position to build upon.

From foundation to scale

The institutional pieces are in place. Greentown Labs, Activate, the Ion and others have built sector-specialized infrastructure most cities would struggle to assemble. Fervo itself is an alum of both Activate and Greentown Labs. Mercury Fund closed its $160 million Fund V, its largest ever. Houston Angel Network, GOOSE Capital, Fathom Fund, and broader pre-seed and seed capital coverage are here. The Houston $10 million-plus Series A list now includes 40 rounds since 2021, which break roughly into two eras. While 2021 to 2022 was biotech-heavy, with companies like Sporos Bioventures, RadioMedix, Cellenkos and Coya Therapeutics, 2024 to 2025 has tilted clearly toward energy, climate, and critical minerals, with Vaulted Deep, Applied Carbon, Mariana Minerals, Sage Geosystems and Ignis H2 Energy among them.

What’s less developed is the volume of seed-stage companies flowing into that capital. Imagine a dozen more Fervos coming out of that infrastructure over the next decade, each generating jobs, recycled founder capital, and the next wave of operators and angel investors. That is the kind of opportunity Houston has within reach if we build the company-formation pipeline to feed it. To be relevant on the national stage as a venture market, and to drive an economy the size of Houston's into the 2030s, the city needs to be doing closer to 20 Series A rounds per month rather than per year. That throughput implies roughly 1,000 seed rounds per year, feeding the funnel at a 20 percent to 30 percent graduation rate. Reaching such throughput depends on how many new founders Houston produces and how quickly our innovation ecosystem can help them achieve lift-off.

Houston in context

The comparative picture brings the scaling challenge into focus. Between 2021 and 2024, Houston-area startups closed between 126 and 153 disclosed venture rounds per year, against a national count between 9,854 and 14,125. That places Houston at a little over 1 percent of the U.S. deal count. For comparison, Austin ran about three times Houston's deal count each year.

At the Series A level, Houston closed between 12 and 24 rounds in any given year. The median Houston Series A across the period was about $10.7 million, compared with $15.4 million in San Francisco. Houston founders are raising fewer and smaller Series A rounds than founders in peer metros, which points directly to where Houston has the most room to grow.

The unicorn picture tells the same story. From 2021 through 2025, the U.S. produced 590 venture-backed unicorns. Four were Houston-based: Solugen and Axiom Space in 2021, Cart.com in 2023, and Fervo Energy in 2024. Adding HighRadius from 2020 brings Houston's all-time total to five. Austin added 19 over the same five-year window. The path from here is to make Houston's entries on lists like these less the exception and more the rule.

Where this leads

Houston has a real opportunity to become the deepest, most credible energy and climate capital market in the country, with the company formation, talent and operator density to support it. The data shows the foundation is already in place. Fervo, Solugen and the growing roster of energy-adjacent Series A graduates are proof. Fervo's IPO is the first of what should be many. Houston has not had a venture-backed cleantech liquidity event of this scale before, and the city now has one to reference, recruit against and build on. With increased company formation at the seed and pre-seed stages, a Fervo-scale outcome need not be a generational event in Houston, but instead, it can become part of a chain reaction powering the city's economy.

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Stephanie T. Schmidt, PhD, is the founder of a stealth startup, a Venture Fellow at Energy Transition Ventures, and an Executive MBA candidate at Rice University's Jones Graduate School of Business. Lawson Gow is the Chief Operating Officer of Greentown Labs. The full Houston VC landscape report is available at Energy Transition Ventures and CleanTech.Org.

Sources: Crunchbase, PitchBook-NVCA, Carta
At Houston event, the Department of Energy’s Advanced Research Projects Agency-Energy announced $100 million in cleantech funding. Photos by Jeff Fitlow/Rice University

National agency announces $100M in funding for energy advancement at Houston event

seeing green

Rice University played host to the first-of-its-kind event from the Department of Energy’s Advanced Research Projects Agency-Energy, or ARPA-E, earlier this month in which the governmental agency announced $100 million in funding for its SCALEUP program.

Dubbed “ARPA-E on the Road: Houston,” the event welcomed more than 100 energy innovators to the Hudspeth Auditorium in Rice’s Anderson-Clarke Center on June 8. Evelyn Wang, director of ARPA-E, announced the funding, which represents the third installment from the agency for its program SCALEUP, or Seeding Critical Advances for Leading Energy technologies with Untapped Potential, which supports the commercialization of clean energy technology.

The funding is awarded to previous ARPA-E awardees with a "viable road to market" and "ability to attract private sector investments," according to a statement from the Department of Energy. Previous funding was granted in 2019 and 2021.

"ARPA-E’s SCALEUP program has successfully demonstrated what can happen when technical experts are empowered with the commercialization support to develop a strong pathway to market” Wang said. “I’m excited that we are building on the success of this effort with the third installment of SCALEUP, and I look forward to what the third cohort of teams accomplish.”

Rice Vice President for Research Ramamoorthy Ramesh also spoke at the event on how Rice is working to make Houston a leader in energy innovation. Joe Zhou, CEO of Houston-based Quidnet Energy, also spoke on a panel about how ARPA-E funding benefited his company along with Oregon-based Onboard Dynamics’s CEO Rita Hansen and Massachusetts-based Quaise Energy’s CEO Carlos Araque.

Attendees were able to ask questions to Wang and ARPA-E program directors about the agency’s funding approach and other topics at the event.

Houston energy innovators have benefited from programs like SCALEUP.

Quidnet Energy received $10 million in funding from ARPA-E as part of its SCALEUP program in 2022. The company's technology can store renewable energy for long periods of time in large quantities.

In January, Houston-based Zeta Energy also announced that it has secured funding from ARPA-E. The $4 million in funding came from the agency's Electric Vehicles for American Low-Carbon Living, or EVs4ALL, program. Zeta Energy is known for its lithium sulfur batteries

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This article originally ran on EnergyCapital.

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Air taxi network to land in 'Texas triangle' of Houston, Austin, DFW next year

taking flight

San Jose, California-based aerospace company Archer Aviation is bringing its air-taxi system to the “Texas triangle” of Houston, Austin and Dallas-Fort Worth.

Currently, the planned zero-emission electric air taxi networks will use Archer’s Midnight air taxi to “turn 60- to 90-minute drives to major airports, business districts and major destinations into 10- to 20-minute flights,” the company said in a news release. Archer plans to begin flights in the Texas triangle next year.

The Midnight air taxi is an all-electric vertical takeoff and landing (eVTOL) aircraft. It can carry four passengers and a pilot and is designed for consecutive flights of about 20 miles.

Archer cites the Texas triangle as one of the busiest and fastest-growing “megaregions” in the country due to its proximity to coastal regions, major airports, and a number of business districts.

Archer Chief Commercial Officer Nikhil Goel described the air taxi experience to CW Houston as “100 times quieter than a helicopter for the price of an Uber Black.” He added that the air taxis are a combination of a helicopter, a small airplane and a drone.

In Houston, Archer’s air taxi network will aim to connect George Bush Intercontinental, William P. Hobby and Sugar Land Regional Airport with downtown destinations, including the Thompson Hotel helipad, and Galveston.

In Austin, it plans to link the city's Austin-Bergstrom International Airport and Austin Executive Airport with the F1 Circuit Helipad at the Circuit of the Americas. Archer debuted its Midnight aircraft at the F1 Prix in the Fan Zone and the F1 Paddock at Austin’s Circuit of the Americas. The Dallas-Fort Worth network is slated to include Dallas-Fort Worth International Airport, Dallas Love Field, Addison Airport, Arlington Municipal Airport, Fort Worth Meacham International Airport and Perot Field Fort Worth Alliance Airport, plus major business hubs like Frisco Station.

“Texas is setting the bar for America’s leadership in the next generation of aviation,” Adam Goldstein, founder and CEO of Archer Aviation, said in the release. “Our planned networks will make the benefits of electric air taxis real for Texans — trading hours in traffic for minutes in the air, while connecting the biggest airports, business districts and sporting hubs in ways that America’s largest megaregion needs to grow.”

Archer is working with state and local partners to develop charging infrastructure and plans to pursue Texas operations through the White House’s eVTOL Integration Pilot Program, according to the release. It recently completed its "No Roads" flight tour, which included multiple flights over the San Francisco Bay, and flew to seven cities over three days.

5 Houston deep tech startups pushing the boundaries of their industries

meet the finalists

Houston has long been at the forefront of innovation, from NASA’s Johnson Space Center to its startup ecosystem using technology to disrupt industries.

As part of the 2026 Houston Innovation Awards, our Deep Tech Business category will honor an innovative startup providing technology solutions based on substantial scientific or engineering challenges, including those in the AI, robotics and space sectors.

Five deep tech companies have been named finalists for the 2026 award.

Read more about these businesses, their founders and their breakthrough technologies below. The 2026 winners will be announced on InnovationMap.com in mid-November.

Casimir

Battery tech startup Casimir develops semiconductor chips that produce continuous electrical power straight from the quantum vacuum, without the need for a battery, cord or external charge source. The company is targeting commercialization for its first-generation MicroSparc chip by 2028.

Harold “Sonny” White founded Casimir in 2023 after nearly two decades at NASA. The company emerged from stealth with a $12 million seed round in 2026. It was also awarded an STTR Phase I contract from the U.S. Space Force's SpaceWERX to support the development of the company's solid-state generator for potential use by the Department of the Air Force earlier this year.

FocisAI

Artificial intelligence startup FocisAI helps refinery owner-operators unlock actionable insights from 3D scans and images.

FocisAI was founded by CEO Tyler Wooten, COO Colin Snell and CTO Kyle Snell in 2026. It is a member of Greentown Labs and launched a seed round in September, which is expected to close by the end of the year, according to the company's application. It has rolled out 10 pilot programs and is looking to move into recurring, facility-scale deployments and scale its team in Houston this year.

Machine Saver Inc.

Industrial tech startup Machine Saver Inc. builds wireless and wired vibration and proximity sensors to tell heavy industry when a machine is about to fail. The company's technology runs on an 8-plus-year battery life and helps operators reduce downtime, improve maintenance and extend equipment life.

Machine Saver was founded by CEO Colton Bach and Quentin Bach in 2013. Its customers and partners include Houston Methodist, Blue Bell, Genemco, as well as energy and heavy industry, food and beverage, and cold chain companies, according to its application. The company is raising a Series A.

Square Robot

Energytech startup Square Robot develops and operates submersible inspection robotics that inspect aboveground storage tanks while they remain in service. The robots reduce downtime and costs, improve worker safety and limit hydrocarbon emissions.

Square Robot launched its Houston office in 2019 and closed a Series B in 2025. It plans to complete its first U.S. Navy demonstrator tank in November and is also developing real-time inspection software.

Venus Aerospace

Spacetech company Venus Aerospace is developing a high-thrust rotating detonation rocket engine (RDRE) that replaces the subsonic combustion used in conventional rocket engines. The RDRE is a compact, simpler engine that can deliver up to 15 percent greater efficiency for defense and space applications. It completed its first U.S. flight test of the engine last summer.

Venus Aerospace was founded in 2020 by CEO Cassie Duggleby and CTO Andrew Duggleby. It raised a $20 million Series A in 2022 and $42 million Series A2 in 2025. It closed a $91 million Series B earlier this year and expanded its leadership team. The company is working toward longer-duration and higher-thrust testing and advancing its flight program.

Houston leads U.S. with the biggest surge in millionaire renters

Rent Report

The number of millionaire renters and homeowners in the U.S. has surged over the last five years, and Houston has soared ahead of the rest with the largest growth rate among these affluent renter households.

Houston leads the nation with the No. 1 increase in millionaire renters from 2020 to 2024, a new RentCafe study found. The number of these wealthy households increased from 18 to 232 over the last five years, representing a 1,189 percent growth rate.

"The pandemic accelerated the shift as remote work pushed the wealthy to relocate to lower-tax metros like Houston, where millionaire renters grew 13-fold, versus 3.9-fold for owners," the report said. "Granted, 232 households is still a tiny fraction of the Houston metro’s roughly 2.7 million households, but the growth rate far outpaces any other major metro."

Nationwide, the number of millionaire renter households grew 229 percent from 2020 to 2024, outpacing the 193 percent growth rate among millionaire homeowners.

Dallas was the only other Texas metro to crack the top 10. The number of millionaire renter households in North Texas has more than quintupled, from just 30 in 2020 to 165 in 2024. That represents a growth rate of 450 percent, which — surprisingly — is only the eighth highest nationwide.

But when it comes to the largest populations of millionaire renters, New York City and San Francisco still lead the way. New York claimed the No. 1 spot with nearly 7,300 millionaire renters living in the city in 2024. Houston ranked 12th on that list.

Elsewhere in Texas, Austin and Dallas ranked as the 16th and 17th, respectively, for the largest population of millionaire renters. There were 206 millionaire renters living in Austin in 2024, and 165 in Dallas.

This is who the typical millionaire renter is
The report also revealed a surprising statistic about the typical millionaire renter in the U.S. — a lot of them are millennials working in "white-collar, high-earning fields."

"Nearly half (49 percent) of millionaire renters are Millennials, and the number of affluent Millennial renter households surged 392 percent during the five-year period," the report said. "Gen X follows with 33 percent of millionaire Gen X households renting after increasing by 147 percent."

The report continued, "Although Gen Z still represents a small share of millionaire renters (just 2 percent of the total), no generation has expanded faster: Gen Z millionaire renter households leaped from fewer than a dozen to more than 400 — a tiny cohort today, but one that was virtually nonexistent five years ago."

The top three most common professions for millionaire renters are chief executives, software developers, and managers, the report additionally found. In Houston, the surge of wealthy newcomers are mostly executives, professional athletes, and entertainers.

"These roles tend to generate steady, substantial income without necessarily tying workers to one location, making renting a practical fit, rather than a financial necessity," the report said.

Hotspots for millionaire homeowners
In RentCafe's separate list comparing the top 10 most popular U.S. metros for millionaire homeowners, Houston ranked 12th nationally with 4,374 millioniare homeowners living in the metro as of 2024. These wealthy Houstonians are most likely working as chief executives, physicians, managers, and lawyers and judges.

Houston has already proven to be a hotspot for millennial homebuyers, and the latest RentCafe data says millennials make up 19 percent of all millionaire homeowners in the U.S. Gen Xers and Baby Boomers still maintain the largest shares of millionaire homeowners nationwide, at 45 and 33 percent, respectively.

Dallas (No. 10) and Austin (No. 20) also appeared among the hottest metros for millionaire homeowners.

Only one Texas city appeared among RentCafe's list of the 20 fastest-growing metros for millionaire homeowners: College Station ranked 13th nationwide with a growth rate of 1,329 percent. From 2020-2024, the number of millionaire homeowners residing in College Station grew from 14 to 200.

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This article originally appeared on CultureMap.com.