Siemens said the deal – which relates to more than 400 of its machines at six Pattern projects – is one of its largest agreements with a single customer in North America.

Siemens will provide service and maintenance at the plants, as well as technology upgrades such as the turbine-maker’s PowerCurve aerodynamic boost.

Alongside operating wind farms, the agreement includes a 10-year deal to look after the Panhandle 2 project in Texas, which Pattern will acquire on operational debut later this year.

Mike