From left: Burt Hamner of Hydrovolts and Ben Finklea of WEND Magazine at the Zino Green Investment Forum. Hydrovolts was named best overall investment opportunity, and Finklea was named best presenter, by audience vote (the plants are the "awards"). Hydrovolts is one of three finalists who have a shot at a $50,000 Zino investment.

There's been a lot of talk about why Seattle, given its green-leaning populace, isn't at the forefront of the clean tech revolution. But some green business competitions are trying to spark a bit of entrepreneurial activity in the sector. Today, the local angel network Zino Society vetted a dozen clean tech startups and chose three finalists -- one of whom will get a $50,000 check.

The finalists are Hydrovolts, which is developing a small, compact "hydrokinetic turbine" that can be dropped into waterways and generate hydropower; TeslaVision, which uses electroluminescent technology to make energy-efficient digital signs; and SpringStar, which is working on non-toxic pest control for mosquitoes.

All 12 companies took part in an afternoon pitch session at Seattle's Pan Pacific Hotel. Zino, which has handed a check to the winner at startup competitions in the past, is taking a slower approach this time. The group will submit the three clean tech finalists to an additional period of due diligence, with the winner announced in May or June.

Is this a sign of investor caution in today's economy? Zino founder and CEO Cathi Hatch said the group is taking more time to do due diligence on investments.

At a panel discussion at the event, Michael Butler, chairman and CEO of Cascadia Capital, weighed in on why Seattle is behind other parts of the country in developing a clean tech sector.

"We don't have a really good working relationship between the public sector and the private sector," Butler said. "It's not just asking for stimulus money. It's tax policy, it's incentives, it's permitting. Government involvement is critical."

Butler added that Seattle should "play to its strengths" in the clean tech sector by emphasizing its expertise in software. "I'm hoping a lot of the software entrepreneurs migrate to the clean tech sector," he said.

It was the third annual green investment forum held by Zino, which has been a vehicle for some $11.9 million in funding for tech startups since 2005.