The detailed report by the Green Investment Bank Commission on how the GIB should function was largely welcomed.

Carbon Trust chief executive Tom Delay said: “We are pleased to see the Wigley report has incorporated our ideas to increase private sector investment and has flagged our low carbon innovation and wider work with business as mission critical to delivering a low carbon economy."

CIWEM executive director Nick Reeves said: “Our carbon targets will be missed unless urgent action is taken to improve access to capital, so we urge the Government to fast track the development of their green bank. They are in a unique position: they can set the UK onto a trajectory of an adaptable, low-carbon society; or go down in history as the Government that failed to act in time.”

ICE director general Tom Foulkes said the report is “a positive step and the Commission clearly recognises the scale of the funding challenge and the need for intervention. The recommendation that such a bank should work in tandem with other Government initiatives and be a permanent institution is also welcome – a long term strategic remit will be vital in creating a stable environment for private investors.

“The report also includes a number of fund raising ideas with real merit - including selling ‘green ISAs’ and recycling cash from infrastructure asset sales such as High Speed 1, which went up for sale last week.”

Danny Stevens, policy director of the Environmental Industries Commission, warned: “There is a risk that a Green Investment Bank will institutionalise a narrow understanding of the economic opportunities of ‘green investment’. If the Bank’s mandate is limited to helping the UK meet the low-carbon investment challenge, the UK risks forfeiting the huge investment opportunities that exist across the whole of the environmental sector. It is vital that Bank embraces a full understanding of the economic opportunities of “green investment.”