Britain has fallen behind countries such as Bulgaria, Chile and Peru on investment in low-carbon energy, and is likely to miss key targets on renewable energy generation without drastic intervention by Alistair Darling, the chancellor, according to two studies published ahead of Wednesday’s Budget.

Investment in “clean” energy in the first quarter of 2009 fell to only £138m ($200m), putting Britain in 15th place in an international league table of green investment compiled by New Energy Finance, a consultancy.