Hydro-Silted dams in 20/30 yrs, submergence of villages-Field day for NGOs. Coal- Green house effect-depleting hydrocarbon source-same with LNG/Oil etc. Wood- Depletion of forest.Same with bio diesel. Solar, wind, tidal- Waiting for the technological breakthrough-billin $ away. So Medha Patkar and co-Are you waiting for cold fusion or that Tamil chap, couple of years ago who was producing petroleum from boiling some wild plants. I dont think any cogent answer will be available from these stupid loud mouths who are the darling of leftist intellectuals and all other assrted asses. Lets ask them the secret source of abundant renewable energy source which we have inherited.