Burradale blades removed for maintenance work

Three of the Burradale windfarm’s five turbines are likely to be out of action for the next couple of weeks as refurbishment and maintenance is carried out.

Having been in operation for over 11 years, owners Shetland Aerogenerators said the blades for the 660kW Vestas turbines – named Mina, Betsy and Brenda – were now in need of restoration work. The other two turbines, Sally and Karen, were erected in 2002 and are expected to require similar work sometime in the next couple of years.

The 23-metre long blades for the turbines were taken down over the past week and transported to the Greenhead Base. The turbines’ routine maintenance is carried out by L&M Engineering, while the specialist work this month will be done by Fred Gibson’s company Shetland Composites.

It will spend the next couple of weeks rubbing down the blades, filling in any blemishes and applying a new type of weather-resistant paint – similar to that used for some aeroplanes – which has been developed for wind turbines.

Shetland Aerogenerators director Angus Ward said the turbines had now been turning for 90,000 hours and have rotated over 15 million miles.

In the last financial year, Burradale’s five turbines produced 53.1 per cent of their maximum output. From April 2011 until March 2012, the windfarm produced 17,152MWh of electricity compared to a theoretical capacity of 32,325MWh.

That is down slightly on Burradale’s most successful year in 2005, when it had a “capacity load factor” of 56.9 per cent, but still makes it what the company believes is “the most productive windfarm in the world”.