Turning point

THEY may be the future of Scottish energy production, but there is nothing more irritating than driving past a large wind farm to see half the blades are not turning.

Experts say a turbine's expected output is based on each running at 30 per cent of its theoretical capacity, taking into account days when the wind hardly blows at all. Other reasons for a lack of rotation include regular maintenance of a specific turbine, or its location in the field, which may be just out of range of where the wind happens to be blowing that day.