If Warren Buffett's maxim to be "greedy when others are fearful" is correct, these corporates will be well rewarded for staying the course.

Clean technology investing has been going through a tough time in the press and investing circles lately, as the wave of optimism in the sector has been tempered by a mature realism dogged by negative headlines.

Yet forward thinking corporate investors are generally looking to invest for the long term in the sector, as my forthcoming feature out in our March issue will document.

A good example of this trend was last week’s EnerVault deal, which saw the four-year…