SCOTTISHPOWER Renewables and Denmark's DONG Energy yesterday unveiled plans to invest £1.6 billion to build one of the largest offshore wind farms in the world in the Irish Sea.

The 389-megawatt West of Duddon Sands joint venture wind farm development with DONG marks ScottishPower’s first offshore marine wind project and will be located some eight miles south-west of the Barrow-in-Furness coastline.

However, a spokesman for ScottishPower Renewables, the UK green energy unit of Spanish power giant Iberdrola, yesterday told The Herald: “This whole project will be managed from our renewables headquarters in Glasgow, and although it will be one of the world’s largest wind farms, West of Duddon Sands will be quickly superseded by forthcoming developments off East Anglia and Tiree.”

ScottishPower is planning to build the 500-turbine Argyll Array development five miles off Tiree, which will have the capacity to generate up to 1800 megawatts of powers.

However, local concerns remain about the impact on the culture and lifestyle of the island, and the Scottish Government is expected to consider the full planning application for the so-called Argyll Array when it is submitted next year, with a final decision expected within the subsequent 12 months.

Also in a planning phase is ScottishPower’s planned 7200 megawatt wind farm off the coast of East Anglia, which is part of a joint venture with Swedish power firm Vattenfall.

The ScottishPower spokesman said the three projects were part of the utility’s previously announced plans to invest £15bn in the UK’s energy infrastructure in the next decade.

Meanwhile, ScottishPower Renewables’ chief executive Keith Anderson said: “West of Duddon Sands will be the first offshore wind project in our pipeline to be commissioned, and marks the start of our extensive investment programme in the offshore wind sector.

“We have over 10 gigawatts of offshore wind farms in development, including the 7.2 gigawatts East Anglia Offshore wind farm, one of the largest proposed renewable energy projects anywhere in the world.”

The West of Duddon Sands installation will consist of 108 Siemens 3.6 megawatt turbines.

The installation and pre-assembly operations will largely be run out of Belfast Harbour, which also stands to benefit from significant upgrade works.

The operational base for the wind farm will be the Port of Barrow, which is also being used for the operation of several other offshore wind farms in the eastern Irish Sea, and will create several hundred jobs locally.

The project will be DONG’s ninth offshore wind farm in the UK and will adjoin its Walney 1 and 2 wind farms in the Irish Sea, which will be commissioned in 2011, the Danish company added.

A spokesman for DONG said: “The production from West of Duddon Sands is expected to be equivalent to approximately 300,000 British households’ annual electricity consumption.”

ScottishPower has attracted ire from politicians and consumer groups after its decision last week to increase average gas bills by 19% and add 10% to its electricity charges, but hit back at its critics by revealing its £15bn UK investment plan.

Parent company Iberdrola, which bought the company four years ago, has also come under renewed scrutiny.