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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


Startup Accelerator and Competition for Promising Cleantech Entrepreneurs Announces May 1 Deadline

by Beth Zonis

For Immediate Release:

Emily Lundberg

Communications Director

Cleantech Open


Sean Davenport

Communications Manager




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Three CTO Alumni Take their Technology Abroad

by Jessica Smothermon


The portfolio of companies that have moved through Cleantech Open's annual accelerator since its launch in 2005 contains a multitude and variety of #CTOAlumniSuccess stories....

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Cleantech Open Northeast Innovation Spotlight: Agriculture & Food Security

by Annie Patyk

This article features the following 2018 Cleantech Open Northeast Graduates: Haystack, OysterTracker, Capro-X, Foodspace, and GreenChoice


When it comes to our food system, we...

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Wells Fargo Innovation Incubator (IN2) Awards CTO Grant and Upswing in VC Cleantech Investment

by Emily Lundberg


Cleantech Investments back on the upswing!

In 2005, when Cleantech Open launched, venture capital investment in cleantech measured just hundreds of millions of dollars. In 2006,...

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