Re: Alternative to Solar
The Hell Gate is comparatively shallow. About a hundred year ago the government tunneled under the river bottom, set off one of the biggest explosions in history, and dropped acres of the bottom down about ten feet in order to gain some depth. (Incredible project, very interesting reading.) So obstructing that passage with anything in the water would be a fast no-go.
The project in the East River, to the west of Welfare Island, was supplying power IIRC to the supermarket on the island but they've spent years trying to get it to work consistently and to study environmental issues like fish kills. Apparently putting windmills underwater just hasn't been working out very well, which is one reason folks are trying "motion" shakers and other concepts.