It 'would' work - but not be very efficient. A car alternator is designed to run at 5-10k rpm, and wind turbines generally run at 60-300rpm. You would need a HUGE gear ratio to get the right speed - and every gear/mechanical speed conversion would impact your efficiency. A DC permanent magnet motor (or custom made stator) is most appropriate. Don't get me wrong - the huge huge wind turbines work on this principle, but thats because they have enough torque to run a more efficient transmission gearbox. Small wind turbines simply...dont.