The sound made by 100 tonnes of steel and carbon fibre rotating 400 feet overhead is surprisingly understated. Each whoosh of the 260 foot blades spans an area the size of the London Eye and generates enough electricity to power the average British home for 24 hours.

There are 32 of these 8MW turbines in the second phase of Dong Energy’s Burbo Bank wind farm spinning off the Merseyside coast.

They are the most powerful ever, dotting an area the size of almost 6,000 football pitches within the Irish Sea, each one a beacon of Britain’s global dominance in the booming offshore wind industry.

Benj Sykes, the UK boss for Dong Energy’s wind power business, predicts he may be cutting the ribbon on turbines with double this power capacity by 2024.

“If you wind the clock back four or five years, this scale of technology was considered very ambitious. Now, you can see them in reality, commercially deployed. It’s very difficult to say where we will ultimately get to,”

he says.

Wind turbines have already more than doubled their power capacity since Dong Energy constructed the first phase of Burbo Bank in 2007 with 3.7MW structures. By the mid-2020s turbines may double again and a capacity of 15MW could be spinning in Europe’s waters.

As the efficiency and power potential of each turbine increases, costs keep falling.

Read more: The Telegraph