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.

CTO BLOG

CTO Alumnus Inergy Solar Named “Top Qualifying Finalist” at 2017 "Entrepreneurship Star” Startup Pitch Contest for Silicon Valley

by Cleantech Open


Congratulations to CTO Alumnus Inergy Solar for being named “Top Qualifying Finalist” at The 2017 "Entrepreneurship Star” Startup Pitch Contest for Silicon...

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Cleantech Open Northeast Accelerator Program Announces Top Cleantech and Energy Startups of 2017

by Cleantech Open

Four companies receive $10,000 in prizes, focusing on information and communications technologies, chemicals and advanced materials, and water and waste

New York City...

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Cleantech Open Alumnus Arcimoto Second Pure EV Company to Go Public, Only After Tesla

by Cleantech Open

At the end of September, the Arcimoto Reg A+ IPO to the NASDAQ was listed and is now trading with the ticker symbol NASDAQ:FUV (which stands for "Fun Utility...

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TWO CTO STARTUPS TIE IN VERGE17 PITCH CONTEST

by Cleantech Open

It’s a Tie: And a Win for Cleantech Open

“Both startups are tributes to the training we do at Cleantech Open, including the process that leads to pitch...

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