In the recipe for slowing global warming, energy efficiency is a critical ingredient. According to the International Energy Agency, improving efficiency could provide more than 40 percent of the reductions in carbon pollution pledged in the Paris Climate Agreement. That’s if individuals, businesses, and governments around the world make full use of the efficiency technologies that already exist.

Jason Hartke is president of the Alliance to Save Energy, a nonprofit urging lawmakers to prioritize energy efficiency...Listen at Yale Climate Connections.