Macquarie, the Australian investment group, is seeking to offload its 25 per cent stake in the Race Bank offshore wind farm in a deal that could be worth £750 million.

The stake is held by Macquarie European Infrastructure Fund 5, a €4 billion fund that was closed in 2016 and is understood to be selling assets as it returns capital to investors, which include pension funds and insurers.

Race Bank is a 573-megawatt project that started generating in 2018. It comprises 91 turbines and lies about 15 miles off Blakeney Point on the north Norfolk coast.

The sale could give the entire wind farm an enterprise value of about £3 billion, sources said.

Macquarie, which declined to comment, is an Australian banking and investment group dubbed the “vampire kangaroo” by its critics. It came under fire for its management of Thames Water during its ownership of the utility from 2006 to 2017. Its British infrastructure assets today include a majority stake in Southern Water, as well as stakes in National Gas, the gas transmission network operator, and Cadent, the gas distribution network operator.

The Race Bank wind farm started life with a seabed lease awarded to Centrica by the Crown Estate in 2003, but the British Gas owner sold the project to Orsted, then known as Dong Energy, for £50 million a decade later after securing planning consent but failing to secure a government subsidy contract. In 2015 Orsted opted to develop the project using a different subsidy scheme and the following year Macquarie bought a 50 per cent stake, split equally between Macquarie Capital, the Australian bank’s own investment arm, and the Macquarie European Infrastructure Fund 5.

Macquarie committed £1.6 billion to buy the stake and to fund its share of the construction costs, although Macquarie Capital sold its 25 per cent stake the following year. Orsted retains a 50 per cent stake, while Sumitomo Corporation and Arjun Infrastructure Partners each hold 12.5 per cent.

The move by Macquarie European Infrastructure Fund 5 to offload its Race Bank stake comes after a deal by the same fund in April to sell stakes in eight other offshore wind farms to Equitix, an infrastructure manager.

Macquarie retains interests in other operational offshore wind farms, including East Anglia One and Sheringham Shoal. It is also developing projects such as Rampion 2, Outer Dowsing and West of Orkney.