I myself work in the power sector. Most of so-called "green energy" sources aren't as environmentally friendly as you might think. Windfarms can and do kill birds and bats.. and a concerning amount of windfarm workers. Also keep in mind that "wind-power" will not grant you any discounts on your energy bill. In fact, I wouldnt be suprised if it increased. The actual cost per megawatt numbers are quite high.
The best investment option would be in nuclear (fission). They are not nearly as dangerous as many might think. In fact, all of the so-called "waste" stored underground is actually recycleable. Currently we (USA) are producing new fuel because it is cheaper, however, europe has been recycling fuel for years.