Put together a group of politicians, chief executives and former finance ministers and you'll have the Global Commission on the Economy and Climate. Set up by seven governments and informed by research organization around the world, the Commission has just issued an opinion about how much it would cost in financial terms to tackle the problem of climate change. The answer?

"Quite affordable".

As new technologies develop, the cost of the solutions gets lower. The prices of wind and solar power have plunged. New policies for equipment and cars are indeed helping the environment.

As one of its member said, "The key message is that we can deliver better growth and tackle climate change at the same time - we don't need to choose".