Forbes “30 Under 30” honors eight Stanford affiliates working in sustainability

The annual “30 Under 30” for North America feature from Forbes this year honors five very recent Stanford alumni, a postdoctoral scholar, a graduate student, and an undergraduate on leave for their early-career contributions to clean energy and other sustainability solutions. Six of the eight were recognized for their cleantech startups. The 2025 group brings the number of Stanford scholars and alumni in sustainability recognized by the magazine over four years to 40.

The Stanford affiliates were highlighted in four categories this year. A postdoc, a student on leave, and one alumnus were recognized in the Energy & Greentech category (links to LinkedIn profiles): postdoc Fabia Farlin Athena, student on leave Tristan Semmelhack, ’26, and alumnus Zhiao Yu, PhD ’22. Two alumni and one student in sustainability made the Manufacturing & Industry category: Halen Mattison, MS ’22, Luke Neise, MS ’22, and Krish Mehta, MS/MBA expected ’24. Sasankh Munukutla, BS ’22/MS ’23, in Social Impact and Savannah Eisner, PhD ’22, in Science round out the Stanford affiliates working in sustainability garnering 2025 Forbes acclaim.

Stanford’s growing cleantech ecosystem partly explains the growing number and breadth of sustainability entrepreneurs recognized by Forbes. Three of the eight are alumni of the Precourt Institute for Energy’s course Stanford Climate Ventures, which teaches students how to begin to commercialize their technologies. In addition, three won Innovation Transfer Program grants from TomKat Center for Sustainable Energy to begin their startups based on technology developed at Stanford. One of the 10 is in her first year of the Precourt Institute’s Stanford Energy Postdoctoral Fellowship. Both the Precourt Institute and the TomKat Center are part the Stanford Doerr School of Sustainability.

30 Under 30 in Energy

In the Energy category, Fabia Farlin Athena (links to Forbes profiles) is working on emerging materials and devices for computing hardware to make artificial intelligence more energy efficient. Emerging non-volatile memories and novel materials like adaptive oxides, oxide semiconductors, and low-dimensional materials have immense potential for low-power AI applications. Born and raised in Bangladesh, Athena earned her doctorate in electrical and computer engineering from Georgia Tech. As a Stanford Energy Fellow under the mentorship of faculty members H.-S. Philip Wong and Alberto Salleo, she is developing high-bandwidth gain cell memory solutions for energy-efficient AI applications.

Forbes also recognized Reflect Orbital, founded by Stanford student on leave Tristan Semmelhack, originally a member of the undergraduate class of 2026, and Ben Nowack, a graduate of Wentworth Institute of Technology. Their audacious startup aims to deliver solar power at night via mirrors in space. The two tested their "sunlight as a service" concept last year by attaching an 8'x8' mirror to a hot air balloon, reflecting sunlight at dusk over the horizon to an area where the sun had already set. The light powered solar panels located in the dark. The team intends to launch many mirrors into low-earth orbit to deliver light for solar power and light’s many other uses. The video of their test has 2.2 million views on X. Reflect Orbital, which has 10 employees including the founders, raised $6.5 million in a seed round led by Sequoia Capital this past September, according to the company website.

"At the highest level, we’re selling sunlight. We’ve developed a system where we can project a 5-kilometer-wide spot of light anywhere in the world after sunset." –Tristan Semmelhack, via Stanford Review

Zhiao Yu is the co-founder and chief technology officer of Feon Energy, which is developing new electrolytes to enable lithium metal batteries. If engineers like Yu can resolve lithium metal batteries’ major flaw – a short lifespan – electric vehicles would become less expensive and go much farther on a single charge. Born and raised in China, Yu earned his Stanford PhD working with chemical engineering professor Zhenan Bao and materials science professor Yi Cui. The other co-founder of Feon is Wenxiao Huang, who was a postdoc at Stanford and is over 30 years old. Yu is an alumnus of the Stanford Climate Ventures course, and he received a TomKat Innovation Transfer grant. Since its founding, Feon has raised more than $8 million in investments.

30 Under 30 in Manufacturing & Industry

Forbes also honored General Galactic, founded by Halen Mattison and Luke Neise. Their proprietary reactor converts captured carbon dioxide into affordable, renewable natural gas and other carbon-neutral fuels. Mattison and Neise’s pilot plant now produces 2,000 liters of renewable fuel daily, the magazine reports. The Stanford spinout has raised $10 million, including an $8-million seed round last month. Mattison, the company's CEO, and Neise, its CTO, earned Stanford master’s degrees in, respectively, mechanical engineering and aeronautics. Both took the Stanford Climate Ventures course. Neise also trained for six months in the Stanford Technology Ventures Program. Prior to General Galactic’s founding, Mattison was an engineer for almost two years at SpaceX.

Krish Mehta is completing master’s degrees in business and in climate technology in the Emmett Interdisciplinary Program in Environment & Resources. At Stanford, Mehta co-founded PHNX Materials, (formerly Phoenix Materials), with former Stanford postdoc Jorge Osio-Norgaard, who is over 30. The early-stage startup focuses on recovering valuable titanium, aluminum and rare earth materials from coal ash landfills. The remaining coal ash is refined into a high-performance supplementary cement-like material, capable of replacing up to 30% of the cement in concrete, slashing carbon emissions. PHNX has raised $3 million from investors. Mehta and Osio-Norgaard benefitted from the Stanford Climate Ventures course, the Innovation for Climate & Sustainability course, and a TomKat Innovation Transfer grant. Mehta is a Knight-Hennessy Scholar at Stanford.

30 Under 30 in Social Impact

In the Social Impact category, Forbes recognized Sasankh Munukutla, who cofounded the startup Terradot with Stanford alumnus James Kanoff, BS ’22. (Kanoff was named a 30 Under 30 honoree three years ago for a separate endeavor in sustainability, the non-profit Farmlink Project.) Munukutla served as a commander in the Singapore Armed Forces for two years before coming to Stanford, where he earned bachelor's and master's degrees in computer science. Using a process called enhanced rock weathering, Terradot applies crushed silicate rock powder to agricultural fields, which then extracts carbon from the atmosphere for 10,000-plus years. This also improves soil health to boost farmers' yields. Munukutla has focused on measuring, reporting, and verifying the quantity of CO2 sequestered, which he has called the key to enhanced rock weathering acquiring the money needed to make it a billion-ton climate solution. He and Kanoff have raised $5.2 million in venture funding from investors that include John Doerr, Kleiner Perkins, and Sheryl Sandberg. Terradot got started with an Innovation Transfer grant in 2022. 

“You have to track the carbon through the soil, into the groundwater, then streams, rivers, and ultimately the ocean, where it is stored for hundreds of thousands of years. Nothing about that is easy.” –Sasankh Munukutla

30 Under 30 in Science

Savannah Eisner is an assistant professor at Columbia University who earned her PhD in electrical engineering at Stanford, working with advisor Debbie Senesky, associate professor of aeronautics and of electrical engineering. Eisner and continued her research for five months as a Stanford postdoc, before departing to become a faculty member at Columbia. Eisner is developing electronics and sensor systems that can survive in space and other harsh environments. She has used the micro and nano-sized devices she has invented for environmental monitoring, as well as hypersonic aircraft and helping NASA explore the surface of Venus.

Bao, Cui, and Senesky are also senior fellows at the Precourt Institute. Cui is also the faculty director of the Sustainability Accelerator at the Doerr School, co-director of the StorageX Initiative, and a senior fellow at the Stanford Woods Institute for the Environment. The Precourt Institute for Energy was founded in 2009 with a gift from Jay Precourt, BS ’59, MS ’60, and his family. The Stanford Climate Ventures course is funded by Tom and Johanna Baruch and offered through the Department of Energy Science & Engineering. The TomKat Center for Sustainable Energy was founded in 2009 with a gift from Tom Steyer, MBA ’83, and Kat Taylor, JD/MBA ’86.