Correlations: Where Renewable Energy Cuts Emissions the Most

Carnegie Mellon University researchers say solar and wind energy projects are most effective at reducing emissions when they lower local reliance on coal plants.

A solar panel in sunny Arizona might produce a lot of electricity, but building more of them brings diminishing returns as they replace relatively low-emission natural gas plants. Those same panels in coal-heavy Indiana or West Virginia, while less efficient, displace dirtier power.