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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.


Cleantech Open Northeast Holds ‘Tell Your Story Day’ in Boston and New York: Entrepreneurs craft narratives that communicate the value of their businesses

by Elise Baker

At the Cleantech Open Northeast ‘Tell Your Story Day’, entrepreneurs had the chance to examine their messages from multiple angles.

Startup founders are required...

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Environmental Performance Software Co. Sustainable Minds Becomes CTO National Sponsor

by Emily Lundberg

Cleantech Open is delighted to announce the addition of new national sponsor Sustainable Minds. The Boston-based cloud software and services company operationalizes...

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Slater Technology Fund Sponsors Four Rhode Island Startups in the 2018 Cleantech Open

by Emily Lundberg

Provides financial support to local entrepreneurs to participate in prestigious accelerator program

Providence, RI, June 18, 2018 – The Slater Technology Fund...

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Preparing for the Next Big Drought: CTO Alumnus Sunvapor Receives $1.5M Award from U. S. Department of Energy

by Emily Lundberg

One-fifth of world's population experience physical water scarcity and 500 million people are about to. Many nations are increasing their investment in desalination...

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