The social cost of carbon was an arcane but important tool in the federal climate toolbox until President Donald Trump targeted it in his sweeping March 2017 executive order to weaken climate actions.
Now, states are taking up the metric.
Policymakers and regulators in several states, including New York, Minnesota, Illinois and Colorado, are using the social cost of carbon to measure and reduce CO2 impacts from their power grids. Some are using it to compensate rooftop solar panel owners who feed low-carbon power in the grid. Others use it to incentivize nuclear power and renewable energy. Their efforts, aimed at reducing planet-warming greenhouse gas emissions, come as Congress and the Trump administration try to restrict its use.
