As the scarcity of fossil fuels grows there will be increasing conflict between nations to secure their supplies in an effort to maintain their carbon-dependent economies. At the same time, there is an inexorably growing human population, destruction of rainforests, depletion of natural resources and plummeting biodiversity. Clearly, this situation cannot be sustained in the longer-term.

Yet our capitalist system is based on the principle of economic growth - growth that is heavily dependent on fossil fuels and unsustainable practices. Just look at recent events; governments are terrified by anything that threatens economic growth – pouring billions of public money into failing financial systems. In addition, many economists see growth not only as desirable but as essential. They claim it lifts the poor out of poverty, feeding the world’s growing population, supporting the costs of rising public spending and stimulating investment and technological development.

The dilemma is how can we square Earth’s finite resources with the fact that as the economy grows, the amount of natural resources needed to sustain that activity must grow too. I am clear in my conviction that economic growth in its current form is unsustainable. We need a new paradigm that limits (or reduces) the global population, a meaningful shift away from fossil fuels to renewable energy, increasing energy efficiency and the adoption of more sustainable lifestyles. This will require courageous, co-ordinated and global government policies that ensure we don’t use up resources faster than the world can replace them.

Many will dismiss this as a utopian ideology. But isn’t it a utopian ideology to carry on blithely down a path that will ultimately lead to catastrophe? Yes, it will require a new world-view and radical changes but I think we have several grounds for optimism. Firstly, sustainable economies are more stable – whilst growth may be lower than in traditional economies it will be more durable in the longer-term and less volatile. Secondly, the shift towards a sustainable economy would create new opportunities, jobs and greater stability. Thirdly, the potential for conflict between nations is reduced as our dependency on fossil fuels reduces over time. Finally, there is a growing recognition (albeit begrudgingly) amongst governments that the current situation is unsustainable and the mood seems to be shifting from one of cynicism and self-interest to one of genuine commitment to tackling the problem.

The prospect of a truly sustainable global economy, fuelled by renewable energy sources coupled with a stabilised human population and harmonised with biodiversity is an ambitious yet achievable goal. But it’s a goal that requires a re-appraisal of the current meaning of economic growth.