Typically, the one-seventh-power law may be considered a
widely acceptable approximation of wind profile. For determination
of the ground friction coefficient, the best fit of a linear regression
in plots between logð~v=voÞ and logðz=zoÞ are performed by
minimizing the sum of the squared errors between all measured
values and the corresponding linear model values. The ground friction
coefficient is estimated from the slope of the linear model. It
can be interpreted that more electrical energy production can be
obtained by installing a larger-size wind turbine at higher