By Steven Nadel

Energy-saving efforts continue to deliver vast gains, but their progress is slowing and will need at least a doubling of investment in order to reach global sustainability goals, according to the International Energy Agency’s new Energy Efficiency 2018 market report, released last week.

The sixth annual report by the IEA, a Paris-based organization formed and led by 30 developed countries, includes striking data on the value of energy efficiency. While global energy use has grown by a third since 2000, the figure below shows that the increase would have been more than 50% greater without efficiency.

However, while efficiency savings are substantial, the IEA finds that the rate of improvement is slowing. The chart below shows that global energy intensity (energy use per unit GDP) fell by 2.5% in 2011, but that the rate of improvement slowed to 1.7% in 2017, and would have dipped even more, to 1.2%, if the 3.9% improvement in China were not included.

The IEA shows the importance of energy efficiency actions to meeting the global sustainability goals of the Paris Agreement.  It provides a “Sustainable Development Scenario” to meet the Paris targets combining energy efficiency with investments in renewable and nuclear energy, fuel switching, and carbon capture and storage. As illustrated in the figure above, 44% of the emissions reductions in this scenario come from energy efficiency — the largest contributor to a plausible scenario reaching the world’s sustainability goals.

Stephen Nadel is the Executive Director of the American Council for an Energy Efficient Economy (ACEEE). This post was excerpted from Nadel’s longer explanation of the IEA report.