気候目標によって持続可能な開発目標の達成にかかる費用が増える可能性がある

Transforming energy systems to meet climate targets could make it costlier to meet the Sustainable Development Goals of providing energy access and food security for all, reports a paper published online this week in Nature Energy. The potential cost of meeting these goals while moving away from fossil fuel use could be in the tens of billions of dollars per year.

Although energy costs have been declining, low carbon energy technologies, such as solar power generators and wind turbines, remain comparatively expensive. Providing the same energy globally using low-carbon technologies could cost as much as 270 billion US dollars more per annum than with the current, largely fossil fuel-based system. The cost of providing clean water and sanitation as well as food security would also rise by 10 and 39 billion US dollars per annum, respectively.

David McCollum and colleagues used six different integrated global economy, environment and energy system models to arrive at these estimates. The models account for the capital costs needed to set up a global low-carbon energy infrastructure and the ensemble enables the authors to report a broad range of estimates covering all eventualities.

These estimates provide a quantitative basis for policymakers to weigh the pros and cons of an energy system transition. They also dispel concerns that switching to low-carbon technologies would be prohibitively expensive and show that, given the scale of global development finance, the change in energy systems is not only necessary but affordable.