The big problem with all of that is that people actually believe that hydro electric dams are "green"

Small run-of-the-river plants emit between 0.01 and 0.03 pounds of carbon dioxide equivalent per kilowatt-hour. Life-cycle emissions from large-scale hydroelectric plants built in semi-arid regions are also modest: approximately 0.06 pounds of carbon dioxide equivalent per kilowatt-hour. However, estimates for life-cycle global warming emissions from hydroelectric plants built in tropical areas or temperate peatlands are much higher. Source cited via hyperlink.

While i agree that Hydro is a good alternative to coal and gas as it produces less co2 emissions, it is not the end all answer for bitcoin.

I will say again, bitcoin is a commodity, as a commodity I would be more likely as someone who cares about what we are doing to our planet to buy bitcoin I could verify was generated via hydro electric power, the real solution has to lay somewhere else. Solar, wind, tidal, something else is the answer, and its adoption by bitcoin miners and users could easily make bitcoin the greenest currency technology in the world. That would take BTC mainstream 1000x faster than any amount of hype/fud/adoption could do. If you could verify-ably say that "this form of currency is supported by a network of green generation and reduces emissions by using it", Bitcoin would become the currency of choice by most of the world almost over night. Maybe not from a federal level, but we all know the power of a decentralized community supersedes any politics or government regulation. Look at the bit license for NY. Early estimates show less than 12% of users, buyers, sellers have complied with the new regulations.  

0 Carbon bitcoins may not be the future now, BUT IT NEEDS TO BE.