| At COP28, international leaders once again fell short of embracing energy efficiency targets, representing perhaps the biggest missed opportunity of the decade. Meet energy efficiency, the magical millions of hard-to-grasp levers that allow us to do more while consuming less energy. It is the result of incremental progress. But too often, it falls by the wayside – despite politicians’ best intentions. “The world’s cheapest energy is the energy that is not used, as we all know, and therefore we set the goal to double energy efficiency by 2030,” Commission President Ursula von der Leyen explained on her trip to the summit in early December. She had wonks hopeful. Going into COP28, Europe had a set of goals: tripling global renewables, getting a commitment to phasing out fossil fuels, and doubling global energy efficiency improvements. The impact of the latter would be humungous. Going all the way to 4% instead of 2% energy efficiency improvements per year would make global climate action child’s play and keep 1.5 °C comfortably within reach. The result – cutting energy use while maintaining economic growth – would deliver 50% of the global climate action needed by 2030, a bigger share than if renewables were tripled. Energy efficiency is measured in production output compared to energy input – and the world has started getting it right in recent years despite pushbacks. | 
