Wind Power in Scotland - Wind Variability

Wind Variability

Most turbines in the European Union produce electricity at an average of 25% of their rated maximum power due to the variability of wind resources, but Scotland's wind regime provides average capacity factor of 21% or higher on the west and northern coasts. The highest load factor recorded for an onshore windfarm was 40% for the North Rhins windfarm near Stranraer, although most other mainland windfarms are very significantly less than this. A small wind farm on Shetland with five Vestas V47 660 kW turbines recently achieved a world record of 58% capacity over the course of a year. This record is claimed by Burradale windfarm, located just a few miles outside Lerwick and operated by Shetland Aerogenerators Ltd. Since opening in 2000, the turbines at this wind farm have had an average capacity factor of 52% and, according to this report, in 2005 averaged a world record 57.9%. However, on some occasions the total generation of Scottish windfarms is less than 2% of rated maximum capacity. On the west and northern coasts Scotland's wind regime can provide an average of 40% or higher.