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The new face of Cleantech innovation

1.2k technology startup entrepreneurs trained
1.2b Dollars Raised
3K clean economy jobs


Since 2005 Cleantech Open (CTO) has trained over 1200 early-stage clean technology startup entrepreneurs through its annual business accelerator. A majority of CTO alumni have survived the merciless technology startup "valley of death" and gone on to raise $1.2 billion and create over 3,000 clean economy jobs.

CTO's one-of-a-kind innovation ecosystem built over the last 11 years 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


The Cleantech Patent Growth Plateau with Two Consumer-Driven Bright Spots: EVs and Smart Homes

by Emily Lundberg

The Cleantech Patent Growth Plateau with
Two Bright Spots: EVs and Smart Homes

According to research conducted by Kilpatrick Townsend and IPWatchdog, the last decade saw...

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Vartega Awarded Small Business Innovation Research Grant from NSF

by Emily Lundberg


Vartega has been awarded a National Science Foundation (NSF) Small Business Innovation Research (SBIR) grant for $224,998 to conduct research and development (R&D) work...

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Innovative Startups Address Pressing Energy and Environmental Challenges

by Annie Patyk and Lauren Skirball

Solutions in waste to power, waste heat reduction, and flex energy storage, featuring 2018 Cleantech Open Alumni AestusHeat Inverse, and Gridpsan Technologies.  


We live...

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Cleantech Open at the Forefront of Social Entrepreneurialism

by Emily Lundberg

Why make the effort? Because the Cleantech Open accelerator’s broad cross-sector approach to innovation promotes cross-pollination with a wide range of business models,...

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