State action to reduce carbon emissions and address climate change can make a big difference, even in the absence of a strong federal climate strategy, according to a new study led by researchers from North Carolina State University (NC State).

The researchers found that, while state measures to tackle climate change are just slightly more expensive than an organized national effort, they would likely lead to the implementation of different decarbonization technologies, a press release from NC State said.

“Given that there is little expectation the Trump administration will promote a national effort to reduce greenhouse gas emissions to address climate change, we think there is significant value in assessing what kind of difference state-led efforts could make,” said study co-author Jeremiah Johnson, an associate professor of civil, construction and environmental engineering at NC State, in the press release.

The research team looked at 23 states whose policy and political indicators suggested that they would be “most likely to consider joint action to reduce carbon emissions,” Johnson said.

“Specifically, we looked at what the cost of such an effort would likely be, which decarbonization technologies would likely be adopted, and the extent to which these efforts could reduce our carbon footprint – and we compared all of these things to the cost, technology, and impact of a coordinated federal effort,” Johnson added.

The team looked at publicly available energy system data for all lower 48 states, including power generation, transportation, building operations and consumer needs like heating and cooling. They then fed the data into decarbonization models that had been adapted to show the impact of changes in specific states.

“We first looked at what the costs and technologies would be if the 23 states that already seemed inclined to strive for net zero carbon emissions actually achieved it,” said lead author of the study Gavin Mouat, a former NC State graduate student. “That would reduce U.S. carbon emissions by about 46% by 2050. We then looked at what the costs and technologies would be if all 48 contiguous states worked together to achieve that same 46% reduction.”

The researchers discovered that the total costs were closer than they had anticipated between efforts led by states and the federal government, with just a 0.7 percent discrepancy. However, the technologies they adopted to reach emissions targets were much different.

“That’s because different states have different resources,” Johnson explained. “For example, some  Great Plains states are excellent locations for establishing wind farms but are less likely to participate in a state-led initiative to address climate change.”

For instance, the research team discovered that industrial decarbonization in a state-led effort played a much more prominent role than it would have in a federal action. They found that an effort by the federal government would depend more heavily on clean energy, like solar and  wind power.

The team also found that there was potential for state efforts to impact pollution in neighboring states.

“Essentially, our model suggests it is possible that non-participating states could increase greenhouse gas emissions, because they might produce a product or service more cheaply for export to those states working to reduce their emissions,” Johnson said. “However, the model also suggests that non-participating states might also reduce their greenhouse gas emissions. This could be due to the fact that clean energy technologies save them money, or because those states may be drawing power from power generation facilities in other states where emissions are falling.”

The findings of the study, “State-led climate action can cut emissions at near-federal costs but favors different technologies,” were published in the journal Nature Communications.

“Ultimately the most important takeaway here is that state-led action can achieve substantial emission reductions, even without federal support, but that the world looks very different than one where there is federal coordination,” Johnson said. “This has some important implications, not just for those states that choose to participate, but also for those who don’t.”

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