Summary
Winners of the largest and longest-running U.S. cleantech accelerator program were announced at Cleantech Open’s 20th Anniversary Global Forum 2025. PolyGone Systems was named U.S. National Winner, and HYDGEN – Hydrogen Innovation Pte earned both Runner-Up and People’s Choice honors, celebrating two decades of cleantech innovation and impact.
Cleantech Open Celebrates 20 Years of Innovation at the 2025 Global Forum
San Jose, Calif. – October 30, 2025 – Cleantech Open, the world’s largest and longest-running clean technology accelerator, celebrated its 20th anniversary at the 2025 Global Forum, held October 27–30 at the San Jose Convention Center and co-located with TRELLIS IMPACT 25. The event brought together more than 90 startups from across the United States and around the world to celebrate innovation, entrepreneurship, and the growing impact of cleantech solutions.
After an inspiring week of pitches, panels, and collaboration, Cleantech Open proudly announced the winners of its 2025 U.S. National Finals:
U.S. National Winner: PolyGone Systems – Developing advanced microplastic filtration systems to protect waterways and ecosystems.
Runner-Up and People’s Choice: HYDGEN – Hydrogen Innovation Pte – Pioneering safe, cost-effective hydrogen transport by reimagining natural gas pipelines.
An exceptional group of companies completed Cleantech Open’s five-month accelerator program this year, gaining mentorship, business training, and access to investors and industry leaders. Ninety-six startups graduated and then competed in regional programs across the country, with the top 18 teams advancing to the National Semifinals at the Global Forum.
Event Highlights
The 2025 Global Forum featured keynote addresses, alumni panels, and networking sessions that highlighted the power of collaboration across the cleantech ecosystem.
Key Speakers Included:
Joel Makower, Chairman and Co-founder, Trellis
Tanya Barham, Founder & CEO, Community Energy Labs (CTO Alum 2020)
Greg Delaune, Co-founder & Executive Director, Deep Blue Institute / Deep Blue Academy and Metro Director for CTO New Orleans, started in 2025.
Rex Northen, Co-founder & Former Executive Director, Cleantech Open
Marc Gottschalk, Former Advisory Board Member, Cleantech Open; Chief Legal Counsel, CALSTART
Ashley Grosh, Vice President, Breakthrough Energy
John J. Berger, Climate and Energy Policy Specialist, Author of Solving the Climate Crisis
Long time volunteers and supporters, Ashley Grosh and Linda Plano, were recognized with Lifetime Achievement Awards for their service to Cleantech Open.
Throughout the four-day event, attendees explored the latest innovations in clean energy, sustainable materials, water, transportation, circularity, and more. The program included startup pitch sessions, alumni showcases, and expert discussions focused on accelerating commercialization and scaling climate solutions.
“Cleantech Open’s impact over the past 20 years has been extraordinary,” said Ken Hayes, Executive Director of Cleantech Open. “Our community of over 4,000 graduated entrepreneurs, 1,000 experienced mentors, and 100 partner organizations continues to drive meaningful progress toward a cleaner, more sustainable future that also achieves business success. We’re proud to celebrate this milestone and the hundreds of companies transforming ideas into real-world impact.”
Sponsors and Partners
Cleantech Open extends its gratitude to the 2025 National Sponsors — Breakthrough Energy Fellows, NREL’s IN2 Innovation Incubator by Wells Fargo, NREL’s GCxN by Shell GameChanger, and CalSEED — for their ongoing support in enabling this year’s accelerator program and Global Forum. Their partnership continues to strengthen the innovation pipeline and empower cleantech entrepreneurs to scale solutions that address the world’s most pressing environmental challenges.
About Cleantech Open
Cleantech Open is the world’s largest and longest-running cleantech accelerator. Over the past two decades, it has supported more than 4,000 entrepreneurs across the United States and globally through mentorship, training, and connections to investors and corporate partners. Cleantech Open alumni have collectively raised more than $4 billion in funding and created thousands of jobs in the clean economy.
To learn more about Cleantech Open visit www.cleantechopen.org and the 2025 Global Forum website.
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