The UK government said today it would sell Green Investment Bank (GIB) to a consortium led by Macquarie Bank in a deal worth £2.3 billion.
The British government set up GIB, which backs green projects with public funds, in 2012 as a commercial venture to spur private investment in green projects.
It has invested more than £2 billion in projects such as offshore wind farms and waste management.
The UK government decided to sell a majority stake in 2015, saying it would give the bank more freedom to borrow, remove state aid restrictions and allow it to attract more capital.
Some lawmakers and environmental groups opposed the sale, saying Macquarie planned to strip the bank of its assets, potentially diluting its purpose of investing in green projects.
The consortium's structure comprises Macquarie Group, Macquarie European Infrastructure Fund 5 and Universities Superannuation Scheme.
It includes a "special share" arrangement whereby GIB's mandate would by safeguarded by five independent trustees, Macquarie said.
Macquarie pledged to keep GIB's target of investing £3 billion in green energy projects over the next three years.
Macquarie added GIB would continue to operate from offices in London and Edinburgh, managing more than £4 billion of green infrastructure assets and projects.
"By combining the Green Investment Bank with the largest infrastructure investor in the world, we will create a market leading platform dedicated to investment in the low carbon economy in the UK and beyond," said Daniel Wong, head of Macquarie Capital, Europe.
"We understand the responsibilities that come with this ownership, and we are fully committed to maintaining its green purpose as we grow the business," he said.
Earlier this month, a court rejected the claim of a rival bidder for GIB, setting the stage for Macquarie to acquire the bank.