First power is flowing for the UK’s £2.5bn ($3.1bn) East Anglia 1 (EA1) offshore windfarm, being jointly developed by Iberdrola-owned ScottishPower Renewables and the Green Investment Group (GIG), in the Southern North Sea.

The lead-off turbine of the 102 SWT-7.0-154 Siemens Gamesa machines making up the project, located 43km off Lowestowft, began turning on 12 September, sending electricity to an onshore substation in Suffolk in south-east England.

Fully operational in 2020, 714MW EA1, one of the ten biggest offshore wind farms being built in European waters, will provide power to over 630,000 homes. Commissioning of further turbines at the development – 25 of which are fully constructed – is underway with production slated to come online “at regular intervals”.

“First power being generated at East Anglia 1 is a huge achievement,” said EA1 project director Charlie Jordan.

“We are continuing to progress towards completion of the offshore wind farm and reaching this point is down to the incredible efforts of everyone involved, from local contractors and employees through to national and international businesses.

“Once operational, [EA1] will produce clean energy the UK needs, while also providing long-term jobs and opportunities to the people and businesses of East Anglia both now and in the future.”

Ed Northam, head of GIG in the UK and Europe, said : “First power is always an important milestone for any project. This is an important project for Suffolk and the UK, and we look forward to the day when all 102 turbines are producing green power.”

EA1, granted a contract for difference (CfD) in February 2015 at a strike price of £119.89/MWh, is the first of four same-named projects that could eventually form a 3.6GW mega-complex in the North Sea, including the 1.2GW EA3, the 900MW EA2, and the 800MW EA1 North projects.

Last month, investment house Macquarie, which owns GIG, has agreed a £1.63bn deal to buy a 40% stake in the project.

Iberdrola said the proceeds of the stake sale will be used to fund its growth plans, which are heavily focused on renewables investment.