Investment in Green Tech

I've been reading a few articles lately about the increasing volumes of venture capital money flowing into green tech ventures. John Doerr has been the central character in just about everyone one of them. This morning I read about a speech he gave this weekend at MIT. One quote I found interesting is "There's too much money chasing too few good ventures, despite the size of this problem." In that speech and other articles, like this one in Fast Company, Doerr describes the green tech sector as bigger than the Internet. The problem is that while the problems being addressed by green tech are considerably large and have enormous market potential, they will take considerably longer to materialize compared to Internet companies. Hopefully investors will have the stomachs to hold on long enough to see the returns and we won't experience a collapse similar to the dot-com bubble.