  Large eddy simulations of wind farms are performed to study the effects of
wind turbine row alignment with respect to the incoming flow direction. Various
wind farms with fixed stream-wise spacing (7.85 rotor diameters) and varying
lateral displacements and span-wise turbine spacings are considered, for a
fixed inflow direction. Simulations show that, contrary to common belief, a
perfectly staggered (checker-board) configuration does not necessarily give the
highest average power output. Instead, the highest mean wind farm power output
is found to depend on several factors, the most important one being the
alignment that leads to minimization of wake effects from turbines in several
upstream rows. This alignment typically occurs at significantly smaller angles
than those corresponding to perfect staggering. The observed trends have
implications for wind farm designs, especially in sites with a well-defined
prevailing wind direction.
