Except for the spinning parts you mean? Those bearings run out and need maintenance. Ontopic: There are some preliminary design for electrostatic wind energy c

Except for the spinning parts you mean? Those bearings run out and need maintenance. Ontopic: There are some preliminary design for electrostatic wind energy converters: see for example http://www.wired.co.uk/article/bladeless-wind-turbine-ewicon http://www.wired.co.uk/article/bladeless-wind-turbine-ewicon