The Clean Tech Open competition, formerly taking entries only from California, is expanding its reach this year by seeking contestants from across the US.

Now in its fourth year, the Clean Tech Open identifies promising green startups and helps them raise funds to begin operations. Over the past year years, the non-profit has helped more than 100 new cleantech companies obtain upwards of $125 million (US) in startup funds.

The competition seeks entries in six areas: Air/Water/Waste, Energy Efficiency, Green Building, Renewable Energy, Smart Power and Transportation.

“When we created the Clean Tech Open, we were focused on creating an ecosystem in which the next generation of innovation and talent could connect with the funding, experience and can-do attitude of Silicon Valley,” said Marc Gottschalk, co-founder of Clean Tech Open. “Having achieved tremendous results, we’re now eager to see what’s next as the competition expands its reach to other parts of the U.S. This is just the beginning.”

This year’s competition will offer one Grand Prize winner the largest prize awards to date, organisers say. Entries must be received by May 30.

Past winners of the Clean Tech Open include Adura Technologies, Aurora Biofuels, Cool Earth Solar, GreenVolts, Lucid Design Systems, NiLA and Syncromatics.

• This fuel-saving stove saves lives too
• Could ‘parasite power’ change the world?
• High-tech David vs Goliath: Smartphones beat IT giants
• How to build the ‘world’s greenest car’? Hit ‘print’
• California utility pilot is part smart meter, part Flickr
• DiCaprio, Nasheed join Zayed Future Energy Prize jury
• Zayed Prize offers $4m for energy innovators
• Cash prizes! Smarter energy?
• IBM opens innovation centre in Mexico
• Crowdsourcing a sustainable future