Evidence of serious flaws in the multi-billion dollar global market for carbon credits has been uncovered by a BBC World Service investigation.

The credits are generated by the UN Clean Development Mechanism (CDM) scheme. The mechanism gives firms in developing countries financial incentives to cut greenhouse gas emissions. But in some cases, carbon credits are paid to projects that would have been realised without external funding.

Arguably, this defeats the whole point of the CDM scheme, set up under the Kyoto climate change protocol, as these projects are getting money for nothing. The programmme aired two projects – one that built a new renewable generator – and one that eleiminated a potent greenhouse gas , that both received carbon credits for doing so, even though both projects would have gone ahead without the carbon credits.