  We introduce a measure for estimating the best risk-return relation of power
production in wind farms within a given time-lag, conditioned to the velocity
field. The velocity field is represented by a scalar that weighs the influence
of the velocity at each wind turbine at present and previous time-steps for the
present "state" of the wind field. The scalar measure introduced is a linear
combination of the few turbines, that most influence the overall power
production. This quantity is then used as the condition for computing a
conditional expected return and corresponding risk associated to the future
total power output.
