TEX-E, a Houston-based energy transition nonprofit, has named Sandy Guitar as its executive director. Photo courtesy TEX-E.

The Texas Exchange for Energy & Climate Entrepreneurship (TEX-E) has named Houston venture capital and innovation leader Sandy Guitar as its new executive director.

Guitar succeeds David Pruner, who will move into the board chair role.

Guitar previously served as general partner and managing director at Houston-based VC firm HX Venture Fund and is co-founder of Weathergage Capital. She also sits on the advisory board of Rice University's Liu Idea Lab for Innovation and Entrepreneurship (Lilie) and launched the Women Investing in VC in Houston group.

In a LinkedIn post, Guitar shared that she's looking forward to bringing her problem-solving skills to the energy transition.

"Innovating in the energy sector is as significant and intricate a problem as I have ever worked on — one that demands creativity, collaboration, and resourcefulness at every turn," she shared.

"I'm honored to join TEX-E at such a pivotal time in the energy transition," she added in a news release. "Energy and climate innovation is accelerating at the intersection of brilliant minds and bold ideas. I'm excited to help TEX-E amplify that collision between students who think differently and the real-world problems that demand fresh solutions."

According to TEX-E, Guitar will continue to lead the organization's programming that aims to connect student climate entrepreneurs with "industry reality."

"Sandy understands the complexities of the Texas energy ecosystem and brings a forward-looking vision for how related innovation can drive meaningful, lasting impact. She's exactly the leader we need to take TEX-E to the next level and help create the next generation of energy transition innovators," David Baldwin, TEX-E board member, added in the release.

TEX-E was founded in 2022 through partnerships with MIT Martin Trust Center for Entrepreneurship and Greentown Labs. It works with university students from six schools: Rice University, University of Houston, Prairie View A&M University, The University of Texas at Austin, Texas A&M University and MIT.

It's known for its student track within the Energy Venture Day and Pitch Competition at CERAWeek, which awarded $25,000 to HEXASpec, a Rice University-led team, at the 2025 event. It also hosted its inaugural TEX-E Conference, centered on the theme of Energy & Entrepreneurship: Navigating the Future of Climate Tech, earlier this year.

HEXASpec was founded by Rice Ph.D. candidates Tianshu Zhai and Chen-Yang Lin, who are a part of Lilie’s 2024 Innovation Fellows program. Photo courtesy of Rice

3 Houston sustainability startups score prizes at Rice University pitch competition

seeing green

A group of Rice University student-founded companies shared $100,000 of cash prizes at an annual startup competition — and three of those winning companies are focused on sustainable solutions.

Liu Idea Lab for Innovation and Entrepreneurship's H. Albert Napier Rice Launch Challenge, hosted by Rice earlier this month, named its winners for 2024. HEXASpec, a company that's created a new material to improve heat management for the semiconductor industry, won the top prize and $50,000 cash.

Founded by Rice Ph.D. candidates Tianshu Zhai and Chen-Yang Lin, who are a part of Lilie’s 2024 Innovation Fellows program, HEXASpec is improving efficiency and sustainability within the semiconductor industry, which usually consumes millions of gallons of water used to cool data centers. According to Rice's news release, HEXASpec's "next-generation chip packaging offer 20 times higher thermal conductivity and improved protection performance, cooling the chips faster and reducing the operational surface temperature."

A few other sustainability-focused startups won prizes, too. CoFlux Purification, a company that has a technology that breaks down PFAS using a novel absorbent for chemical-free water, won second place and $25,000, as well as the Audience Choice Award, which came with an additional $2,000.

Solidec, a company that's working on a platform to produce chemicals from captured carbon, and HEXASpec won Outstanding Achievement in Climate Solutions Prizes, which came with $1,000.

The NRLC, open to Rice students, is Lilie's hallmark event. Last year's winner was fashion tech startup, Goldie.

“We are the home of everything entrepreneurship, innovation and research commercialization for the entire Rice student, faculty and alumni communities,” Kyle Judah, executive director at Lilie, says in a news release. “We’re a place for you to immerse yourself in a problem you care about, to experiment, to try and fail and keep trying and trying and trying again amongst a community of fellow rebels, coloring outside the lines of convention."

This year, the competition started with 100 student venture teams before being whittled down to the final five at the championship. The program is supported by Lilie’s mentor team, Frank Liu and the Liu Family Foundation, Rice Business, Rice’s Office of Innovation, and other donors

“The heart and soul of what we’re doing to really take it to the next level with entrepreneurship here at Rice is this fantastic team,” Peter Rodriguez, dean of Rice Business, adds. “And they’re doing an outstanding job every year, reaching further, bringing in more students. My understanding is we had more than 100 teams submit applications. It’s an extraordinarily high number. It tells you a lot about what we have at Rice and what this team has been cooking and making happen here at Rice for a long, long time.”

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This article originally ran on InnovationMap.

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Houston geothermal company raises $97M Series B

fresh funding

Houston-based geothermal energy startup Sage Geosystems has closed its Series B fundraising round and plans to use the money to launch its first commercial next-generation geothermal power generation facility.

Ormat Technologies and Carbon Direct Capital co-led the $97 million round, according to a press release from Sage. Existing investors Exa, Nabors, alfa8, Arch Meredith, Abilene Partners, Cubit Capital and Ignis H2 Energy also participated, as well as new investors SiteGround Capital and The UC Berkeley Foundation’s Climate Solutions Fund.

The new geothermal power generation facility will be located at one of Ormat Technologies' existing power plants. The Nevada-based company has geothermal power projects in the U.S. and numerous other countries around the world. The facility will use Sage’s proprietary pressure geothermal technology, which extracts geothermal heat energy from hot dry rock, an abundant geothermal resource.

“Pressure geothermal is designed to be commercial, scalable and deployable almost anywhere,” Cindy Taff, CEO of Sage Geosystems, said in the news release. “This Series B allows us to prove that at commercial scale, reflecting strong conviction from partners who understand both the urgency of energy demand and the criticality of firm power.”

Sage reports that partnering with the Ormat facility will allow it to market and scale up its pressure geothermal technology at a faster rate.

“This investment builds on the strong foundation we’ve established through our commercial agreement and reinforces Ormat’s commitment to accelerating geothermal development,” Doron Blachar, CEO of Ormat Technologies, added in the release. “Sage’s technical expertise and innovative approach are well aligned with Ormat’s strategy to move faster from concept to commercialization. We’re pleased to take this natural next step in a partnership we believe strongly in.”

In 2024, Sage agreed to deliver up to 150 megawatts of new geothermal baseload power to Meta, the parent company of Facebook. At the time, the companies reported that the project's first phase would aim to be operating in 2027.

The company also raised a $17 million Series A, led by Chesapeake Energy Corp., in 2024.

Houston expert discusses the clean energy founder's paradox

Guest Column

Everyone tells you to move fast and break things. In clean energy, moving fast without structural integrity means breaking the only planet we’ve got. This is the founder's paradox: you are building a company in an industry where the stakes are existential, the timelines are glacial, and the capital requires patience.

The myth of the lone genius in a garage doesn’t really apply here. Clean energy startups aren’t just fighting competitors. They are fighting physics, policy, and decades of existing infrastructure. This isn’t an app. You’re building something physical that has to work in the real world. It has to be cheaper, more reliable, and clearly better than fossil fuels. Being “green” alone isn’t enough. Scale is what matters.

Your biggest risks aren’t competitors. They’re interconnection delays, permitting timelines, supply chain fragility, and whether your first customer is willing to underwrite something that hasn’t been done before.

That reality creates a brutal filter. Successful founders in this space need deep technical knowledge and the ability to execute. You need to understand engineering, navigate regulation, and think in terms of markets and risk. You’re not just selling a product. You’re selling a future where your solution becomes the obvious choice. That means connecting short-term financial returns with long-term system change.

The capital is there, but it’s smarter and more demanding. Investors today have PhDs in electrochemistry and grid dynamics. They’ve been burned by promises of miracle materials that never left the lab. They don't fund visions; they fund pathways to impact that can scale and make financial sense. Your roadmap must show not just a brilliant invention, but a clear, believable plan to drive costs down over time.

Capital in this sector isn’t impressed by ambition alone. It wants evidence that risk is being retired in the right order — even if that means slower growth early.

Here’s the upside. The difficulty of clean energy is also its strength. If you succeed, your advantage isn’t just in software or branding. It’s in hardware, supply chains, approvals, and years of hard work that others can’t easily copy. Your real competitors aren’t other startups. They’re inertia and the existing system. Winning here isn’t zero-sum. When one solution scales, it helps the entire market grow.

So, to the founder in the lab, or running field tests at a remote site: your pace will feel slow. The validation cycles are long. But you are building in the physical world. When you succeed, you don’t have an exit. You have a foundation. You don't just have customers; you have converts. And the product you ship doesn't just generate revenue; it creates a legacy.

If your timelines feel uncomfortable compared to software, that’s because you’re operating inside a system designed to resist change. And let’s not forget you are building actual physical products that interact with a complex world. Times are tough. Don’t give up. We need you.

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Nada Ahmed is the founding partner at Houston-based Energy Tech Nexus.

Houston maritime startup raises $43M to electrify cargo vessels

A Houston-based maritime technology company that is working to reduce emissions in the cargo and shipping industry has raised VC funding and opened a new Houston headquarters.

Fleetzero announced that it closed a $43 million Series A financing round this month led by Obvious Ventures with participation from Maersk Growth, Breakthrough Energy Ventures, 8090 Industries, Y Combinator, Shorewind, Benson Capital and others. The funding will go toward expanding manufacturing of its Leviathan hybrid and electric marine propulsion system, according to a news release.

The technology is optimized for high-energy and zero-emission operation of large vessels. It uses EV technology but is built for maritime environments and can be used on new or existing ships with hybrid or all-electric functions, according to Fleetzero's website. The propulsion system was retrofitted and tested on Fleetzero’s test ship, the Pacific Joule, and has been deployed globally on commercial vessels.

Fleetzero is also developing unmanned cargo vessel technology.

"Fleetzero is making robotic ships a reality today. The team is moving us from dirty, dangerous, and expensive to clean, safe, and cost-effective. It's like watching the future today," Andrew Beebe, managing director at Obvious Ventures, said in the news release. "We backed the team because they are mariners and engineers, know the industry deeply, and are scaling with real ships and customers, not just renderings."

Fleetzero also announced that it has opened a new manufacturing and research and development facility, which will serve as the company's new headquarters. The facility features a marine robotics and autonomy lab, a marine propulsion R&D center and a production line with a capacity of 300 megawatt-hours per year. The company reports that it plans to increase production to three gigawatt-hours per year over the next five years.

"Houston has the people who know how to build and operate big hardware–ships, rigs, refineries and power systems," Mike Carter, co-founder and COO of Fleetzero, added in the release. "We're pairing that industrial DNA with modern batteries, autonomy, and software to bring back shipbuilding to the U.S."