In some of the best stories, a supposed villain turns out to be a hero. Environmental campaigners are recovering from just such a surprise after hearing the Virgin boss Sir Richard Branson promise to commit all the profits from his transport companies over the next 10 years – a projected $3 billion (£1.6 billion) – to develop renewable forms of energy.

This giddy feeling is becoming more frequent. Not only has a former US vice president released a documentary on global warming, An Inconvenient Truth, but the current President, himself a former oil magnate, recently challenged his country’s ‘addiction to oil’ and pledged massive financial support for research into cleaner fuels. Meanwhile, a consortium of British big-business leaders has sent an open letter to the Prime Minister urging tougher regulation of carbon emissions.

People who understand big business are not so disorientated, however. Many of its representatives have been saying for some time that greater curbs on CO2 emissions would encourage innovation and increase their companies’ competitiveness in the global marketplace.

There is a secret here that those who align themselves uncritically with the green movement often fail to grasp: big business is generally only too willing to change the way it operates in accordance with the social and environmental concerns of consumers, because doing so increases its market opportunities. That is, after all, how big business stays big.

It’s also the reason why oil companies are no longer interested only in oil. Hydrogen energy is a major concern for Shell, and BP now stands for ‘beyond petroleum’. Car companies, similarly, are engaged in a frenetic race to develop cheap and reliable clean-fuel vehicles.

It’s not merely the depletion of oil reserves that motivates such companies. They want to get ahead of demand so they can capture new markets. They therefore regard regulation as a guarantee that, in the long run, their investment in green technologies will pay off.

Branson’s putative $3 billion is not a donation. It’s an investment in his renewable-energy business, Virgin Fuel. That’s why his announcement is good PR, even though it can’t be dismissed as merely PR.

Poachers are turning game-keepers as they discover the vision and commitment to convert an inconvenient truth into a convenient one. At the deepest level - as Christians understand - what is good also turns out to be what is good for us. In this sense, there is a transformative power in enlightened self-interest. And it is this that will save our planet.

Peter Heslam

Peter Heslam is associate faculty at LICC and director of Transforming Business at Cambridge University.