To mitigate the worst effects of global climate change, we need to reduce our emissions of greenhouse gases. One of the cheapest ways to reduce emissions is to reduce our demand for energy by promoting better efficiency in our industrial processes, our homes and our appliances. But can businesses and investors make money by reducing demand?

Diana Farrell, Director of the McKinsey Global Institute, made the case for investing in energy efficiency at the recent UN/Ceres Investor Summit on Climate Risk.