Third-quarter 2005 investments in North American cleantech start-ups hit $425 million, according to data from industry analyst Cleantech Venture Network. That was a 37% increase on the same quarter in 2004 and the largest quarterly investment in the sectors history. 

Erik Straser, of Mohr Davidow Ventures said he expected investments to grow as more mainline firms take an interest and the established cleantech investors start to invest funds raised in 2005.

Bottom Line: start to look at mainline VC investors as a potential investing source. But be prepared to educate if you are outside solar.