Wind turbines of a wind power plant may be selectively over-rated by measuring the difference between the nominal and actual power plant outputs and deriving an over-rating request signal based on that difference which is sent to each turbine. The same value may be sent to each turbine. Alternatively, each turbine may be given its own over-rating amount based on an optimization of the turbine. Over-rating may also be used when external economic factors such as energy costs are sufficiently high to out-weigh any potential harmful effect of over-rating. The fatigue lifetime of turbines and their critical components may also be taken into account when deciding whether and to what extent to implement an over-rating command.