The largest rooftop solar array in the United States is currently under construction at the Mandalay Bay in Las Vegas.

That might be surprising in itself, but it's only the latest in a series of moves by big casinos to go green. But not everyone's happy about it, especially NV Energy, the major electric utility which serves the entire state.

What's happening in Las Vegas isn't unique, it's actually an illustration of the difficulty faced in communities across the nations that are trying to balance new methods of sustainability with older infrastructure. 

 Daniel Hernandez wrote about this for The Guardian and he joins Alex Cohen for a discussion.