The market in carbon credits tripled last year to $30bn from $10bn in 2005, the World Bank said yesterday. Financial Times

But the fledgling carbon credit industry is struggling to keep up with demand, as there is now a shortage of skilled technicians to monitor carbon reduction projects and verify the claimed emissions cuts are taking place.

Nearly $25bn (£13bn) came from transactions under the European Union’s emissions trading scheme, while $5bn was from the sale of carbon credits by developing countries.

China was the biggest beneficiary. The world's fastest-growing economy sold 61% of last year’s carbon credits, while India took 12% and Brazil 4%.

The UK was the biggest purchaser of credits, buying 50% of supply.