Alstom to connect North Sea windfarm to German grid

Alstom has entered Germany’s offshore high-voltage direct current (HVDC) market with a €1bn contract to connect an offshore windfarm project in the North Sea to the German mainland.

Awarded by TenneT, the contract calls for onshore and offshore converter stations plus connecting cable systems for the DolWin3 offshore wind project.

The DolWin3 project will be the third grid connection in the DolWin wind farm cluster in the south-western region of the North Sea and will offer a capacity of 900MW.

Once the project is complete in 2017 DolWin3 will be the eighth grid connection project to be implemented by TenneT using DC technology.

‘The contract is for the engineering, design and construction of the platform which is going to connect five windfarms and around 200 wind turbines to produce up to 900MW that will be connected to onshore grid of Germany,’ said Patrick Plas, senior vice-president, Alstom Grid Power Electronics and Automation.

‘The scope of the contract covers the turnkey supply and construction of the offshore converter station, which includes the platform itself, the complete converter system onshore – including construction works – and the DC cable connection between these two stations,’ he added. ‘The cable connections include 80km on the seabed and 80km onshore to connect the offshore platform to the onshore platform.’

Alstom will execute the contract with platform builder Nordic Yards and cable supplier Prysmian. Plas added that 65 staff will join a team of more than 120 working on offshore projects in Germany. In the UK, Alstom Grid in Stafford will receive around £125m of the contract for engineering and design of the converter stations and anticipates dozens of new jobs at the site.

Plas said that Alstom has extensive experience in HVDC, adding that the company had previously employed it in non-synchronised networks in the Gulf states; in so-called energy highways to transport electricity over long distances in India, China and Brazil, and to connect renewable energy sources to electricity grids.

Looking forward, Plas believes the HVDC market will reach €50bn between 2013 and 2020.

‘It is growing very fast, between €3 and €4bn in 2012/13 and accelerating,’ he said. ‘This is especially impacted by the connections of offshore wind platforms, a market that is important in Europe, which represents 90 per cent of the world market, particularly in the UK and Germany.’