More evidence of the trend of generalist investors getting into cleantech investing: Founder and Managing Director David Rubenstein told attendees at a private equity conference in Germany that the firm intends "to be much more active in the wind, power, solar energy, biomass and geothermal areas." The article describing his speech also mentions that Carlyle will be raising a private equity fund to specifically focus on renewable energy infrastructure. Rubenstein's statements probably relate primarily to the firm's later stage investment activities, but there's reason to believe this approach will extend into the firm's early-stage investments as well.

In any case, as later stage financial investors get more active in cleantech, it improves the possibilities for M&A exits and for project financing for venture investors' portfolio companies. The cleantech "ecosystem" continues to fill out nicely...