Cleantech Open

Startup accelerator · run by Cleantech Open · United States

Long-running American cleantech accelerator run by volunteer mentors, with regional programmes feeding a national showcase.

Apply on the programme's own site

Cleantech Open terms

Read from the programme's own page on September 13, 2026, and re-read every morning. A figure nobody states is left empty rather than estimated.

Equity taken
75%
A majority of CTO alumni surveyed have survived the merciless technology startup “valley of death” and gone on to raise over $3 billion equity, and in recent cohorts, 75%+ of Teams contain members who identify as BIPOC and/or women. check it
Cost to apply
application fee
You will be prompted to pay the application fee after you finish filling out the application itself but before you can successfully submit it for judging. check it

An accelerator is one door. There are 10,471 others.

Pitch2Fund holds the venture funds, family offices and angels who back what you are building — their portfolios, their partners, and an outreach email written for each one. Free, alongside whatever you apply to.