Danish utilities DONG Energy has received the final investment decision from authorities to construct the 660MW Walney Extension Offshore Wind Farm in the Irish Sea, which will deliver electricity to more than 460,000 UK homes.

DONG Energy’s executive vice president Samuel Leupold said: “Walney Extension will deliver clean electricity to more than 460,000 UK homes and I’m very glad that we can now start construction of what will be the world’s biggest offshore wind farm when completed.

“Building this offshore wind farm will bring us significantly closer to realising our strategy of having 6.5GW of installed capacity online by 2020.

“British offshore wind has seen phenomenal growth in recent years. A prerequisite for long-term growth in the industry is that offshore wind eventually can compete on costs with other energy technologies. Building Walney Extension will bring us one step closer to that target and I’m satisfied to see that we keep bringing costs down, while continuing to expand the UK supply chain.”

Expected to be commissioned in 2018, the Walney Extension will be bigger in size than the 630MW London Array Offshore Wind Farm, also commissioned by DONG in 2014. The company confirmed that construction of the Walney Extension would see turbine blades, parts of the foundation and cable installations sourced from UK manufacturing facilities and provide local job opportunities.

Operating under the UK’s Electric Market Reform, DONG Energy can use the Final Investment Decision aspect of the regime, enabling the company to fast-track the project with an as-yet-unspecified fixed price for the first 15 years of production.

Once the Walney Extension and other ongoing projects across the UK and Germany are completed, the group will have a total built capacity of 5,089MW – enough to counteract the electricity consumption of 12.5 million people.

Winds of fortune

The Walney Extension represents the third giant offshore announcement from DONG Energy over the past three months.

In August, the group announced the acquisition of the Hornsea Zone which has the potential to create up to 3GW of electricity. Earlier this month, a 312MW offshore wind project co-owned by DONG and Lego Group was inaugurated in Germany – a project which is expected to produce enough clean electricity to supply 320,000 German households each year.

DONG Energy’s announcement comes at a particularly prosperous time for the wind energy sector. Research published earlier this month by Bloomberg New Energy Finance (BNEF), revealed that the global average levelised cost of electricity (LCOE) produced from offshore wind has fallen from $176 per Mwh to $174 in the second half of 2015, making it cheaper than some fossil fuels.

Matt Mace

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