http://www.indiegogo.com/Energy-from-Water
It seems like a lot of complication when the problem can be solved by inlet design at a much lower cost with no wear potential of significance.
Water Turbine
Water Turbine
Engineering is the art of making what you want from what you can get at a profit.
Non-positive-displacement variation of an old positive-displacement theme:
http://www.google.com/patents/US769082 (1904)
http://www.google.com/patents/US2482325 (1949)
http://www.google.com/patents/US3277792 (1966)
http://www.google.com/patents/US769082 (1904)
http://www.google.com/patents/US2482325 (1949)
http://www.google.com/patents/US3277792 (1966)