•We examine the effect of human capital on energy consumption for a panel of OECD economies over the period 1965–2014.•Our results suggest that human capital reduces aggregate energy consumption by 15.36%.•We find that human capital is associated with a 17.33% decrease in dirty energy consumption and an 85.54% increase in clean energy consumption.•Our findings emphasize the social benefits of investing in human capital We examine the effect of human capital on energy consumption for a panel of OECD economies over the period 1965–2014. Our preferred results, which account for cross-sectional dependence and structural breaks, suggest that a one standard deviation increase in human capital reduces aggregate energy consumption by 15.36%. When we distinguish between clean and dirty energy consumption, we find that human capital generates significant positive externalities for the environment. Specifically, we find that a one standard deviation increase in human capital is associated with a 17.33% decrease in dirty energy consumption and an 85.54% increase in clean energy consumption. Our findings reinforce the social benefits of investing in human capital and suggest a promising avenue for energy conservation without impeding economic growth.