CleanTech Accelerators in California (2026)
California is the world's largest cleantech market, and its accelerator ecosystem for climate and clean energy founders is correspondingly substantial. LACI (Los Angeles Cleantech Incubator) runs accelerator cohorts combining some non-dilutive grant-style support with pilot partnerships, particularly with LA-area utilities and the City. Third Derivative (RMI and New Energy Nexus partnership with CA cohort activity) runs thematic climate accelerator cohorts. Elemental Excelerator, while Hawaii-headquartered, has significant California cohort and portfolio activity with substantial non-dilutive check sizes. Activate (formerly Cyclotron Road at LBNL) is a fellowship-style program for hard-tech climate founders based in Berkeley that provides two years of non-dilutive support — one of the strongest programs for hardware climate founders. Y Combinator has accepted growing numbers of climate founders in recent cohorts. Greentown Labs' satellite programming and corporate accelerator partnerships with Shell, Engie, and others reach California. Bootstrap Directory aggregates California cleantech accelerators across equity and non-dilutive models, so founders can evaluate programs side-by-side by check size, lab access, pilot partners, and eligibility rather than evaluating each program in isolation.
Frequently Asked Questions
What is Activate?
Activate (formerly Cyclotron Road) is a two-year fellowship program based at Lawrence Berkeley National Lab (plus Boston and Houston locations). It provides substantial non-dilutive stipend support and lab access to hard-tech climate and energy founders. Activate fellows retain full equity — it's one of the strongest pure non-dilutive programs for climate hardware founders in the U.S.
How does LACI work?
LACI (Los Angeles Cleantech Incubator) is a nonprofit incubator-accelerator based in LA's Arts District. Programs combine cohort support, non-dilutive grant components, lab and office space, and pilot opportunities with LA-area utilities and the City. Cohorts focus on specific climate verticals (mobility, energy, circular economy, water).
When do California cleantech accelerators run?
Activate fellowships have annual application cycles. LACI runs multiple annual cohorts. Third Derivative and Elemental have their own cadences. Y Combinator runs 2x annually with climate tracks. Bootstrap Directory tracks current California cleantech accelerator applications.