Ideally, stand-alone turbines should be sited as far away as possible from buildings or trees, which may block the wind and cause turbulence. As a guide, the wind turbine should be about twice the height of obstructions in the immediate front of it (for at least the prevailing wind direction). In general, the turbine should be above the height of nearby obstructions that are within a distance of 10m to 60m of the tower heights.