Cleantech Open runs the largest clean technology accelerator program in the world.


Technology Startups


Entrepreneurs Trained


Total Dollars Raised


and/or Women (2023)

Since 2005 Cleantech Open (CTO)  has trained over 3,750 entrepreneurs from 2,000 early-stage clean technology startups through its annual business accelerator. A majority of CTO alumni surveyed have survived the merciless technology startup “valley of death” and gone on to raise over $1.8 billion equity, and in recent cohorts, 50% of founder CEOs self-identified as BIPOC and/or women.

CTO’s one-of-a-kind innovation ecosystem built over the last decade and a half of programming spans key cleantech innovation hubs in the U.S. and globally. As a non-profit organization run largely by volunteers, there are many ways to contribute. Join our global network of innovation and together let’s forge a clean and sustainable future.

National Sponsors

Apart from the free survey software, we also have access to QuestionPro's free survey templates . We've found many of them useful and powerful to collect insights from various stakeholders of our organization.