A year is a long time in politics, the old adage goes. The same might be said of cleantech too.

It is over a half year, since in our “ten predictions for 2010”, we anticipated a rise in investor exits in 2010. Our assertion in November 2009 was that growth and venture capital investment activity would be buoyed by attractive valuations and the return of the exit. We wrote, “exits in the form of IPOs (A123Systems went public in September, and there are over two dozen IPOs now in the queue) and a growing number of trade sales to corporate buyers will encourage investors in private companies to believe they can generate returns.”

It is nearly a year since, in partnership with the Guardian, we published the first Global Cleantech 100, a list of the 100 private cleantech companies most likely to make the most significant market impact over the next 5 to10 years – according to the world’s cleantech community.

If ever there was a list of cleantech companies where one would have expected exit action over the last months, it would have been this. However, the relative small amount of exit turnover on the list is well-aligned …