To reach its global and European commitments on carbon reduction by 2020, the UK must replace 40% of its energy production. How will we achieve this and which fuel sources offer the best options to do so?

The "low-carbon economy" has become one of the most repeated buzzwords in the debate about climate change - the ultimate goal of any policymaker. In basic terms, it's an economy that minimises its output of damaging greenhouse gases. We have global agreement, at least in principle, that reducing carbon emissions must be a priority.

So far, so simple. Yet in practice it has been anything but straightforward. Following the global economic crisis in 2008, there were strong arguments for focusing on the green economy as a way to kick-start growth. Building low-carbon infrastructure involves developing renewable energy generation, improving public transport networks, creating smarter and more flexible electricity grids, "retrofitting" buildings to increase their energy efficiency, and working on carbon capture and storage technology.

These developments would provide jobs for thousands of people. However, substantial public-sector investment would be needed to galvanise these projects in any meaningful way, and at a time of austerity such funding is not forthcoming.

Of equal importance to these economic constraints - if not greater - is the difficulty of reaching global consensus. The single biggest step so far towards a low-carbon economy was the Kyoto Protocol, which came into force in 2005 and has been ratified by all industrialised nations except the United States.

But since then, progress has come to a halt. Hopes were high in the run-up to the 2009 Copenhagen summit, which descended into a farce of indecision. Until nations agree to act together, none will be willing to reduce their carbon emissions substantially, for fear of losing out to global competitors. It is particularly important in this that developing nations be engaged as equals.

This failure to reach political accord will be reversed only when leaders start to see the low-carbon economy as an integral part of economic recovery, not a hindrance to it.