WIND farms are set to keep producing electricity for many more years than expected thanks to a new turbine refurbishment programme by a leading manufacturer.

Gamesa, a Spanish group with growing interests in Scotland, is thought to be the first operator to launch the new service as part of its maintenance activities. It claims it can add around 10 years' life expectancy to turbines, which are currently estimated to last for 20 to 25 years.

Turbine refurbishment is set to become a growth industry now the earliest wind farms are coming to the end of their lives, and offers the possibility of preventing overall green electricity output from falling as they come offline. It also raises questions for subsidies. They currently expire after 15 years but have the potential to be renewed after refurbishment - however, Prime Minister David Cameron told parliament a few days ago of his intention to "roll back" green subsidies in the midst of the row about rising energy bills.

Gamesa is also in negotiations about subsidies for refurbished turbines in Spain, which has frozen all future assistance as part of efforts to reduce government debt.

Global senior vice-president Fernando Valldeperes said: "Gamesa has been asked by the EC to come up with a standard process for life extensions for the whole of Europe, for which we had the first meeting last month … we've also been working with [green energy consultancy] Garrad Hassan to help them with this."

Gamesa has signed a memorandum of understanding with Forth Ports over a plan to set up a manufacturing base for offshore turbines at Leith.