The great turn away from fossil fuels promises a world less choked by its own exhaust, a future where clearing the air is a welcome, life-saving parallel to cooling the planet. Yet, according to a new synthesis by energy and policy researchers, this cleaner, healthier future is not a guaranteed destination, but a path that must be deliberately chosen, lest we simply trade one set of problems for another.
Wei Peng, an assistant professor at Princeton University, alongside a team of colleagues and graduate students, argues in a recent perspective in Nature Reviews Clean Technology that focusing solely on carbon emissions is a narrow view that misses both risks and opportunities. While a national decline in air pollution is likely, the local picture is far more complex, and the health benefits will not simply rain down evenly upon everyone.
“It’s well-established that if we transition from coal to less-polluting energy sources, in almost every case, we’re going to have cleaner air and better health at a national level,” Peng said. “But nobody really lives at that national average exposure level.”
The clean energy transition, it turns out, can have its own smoggy complications. Consider the electric vehicle, that gleaming symbol of a low-carbon future. While city dwellers may breathe easier without tailpipe emissions, the researchers note that new air pollution hotspots could spark to life in rural areas where the power plants that charge them, or the factories that build them, are located.
“While there may be a net increase in air quality and health benefits at a national or international scale, those benefits won’t be evenly distributed across communities,” said Jinyu Shiwang, a graduate student in Peng’s group.
The work of connecting an energy policy to a health outcome is a formidable chain of cause and effect, involving complex models of energy demand, atmospheric science, and population vulnerability. A remote power plant might emit more, but affect fewer people, than a smaller source in a dense urban center. The elderly and the young are more susceptible. Weather patterns shift pollution hundreds of miles.
The researchers contend that the most powerful way to build broader support for clean energy is to speak of these immediate, local health gains. “Whereas mitigating greenhouse gases is a global challenge, better health outcomes are direct benefits that people can see for themselves,” Shiwang said.
The path forward, they suggest, is not to build ever more complex models, but to work directly with states and cities, tailoring analysis to their specific problems. It requires designing for equity from the start, not assuming it will naturally emerge.
“We cannot simply measure success in terms of tons of CO2 avoided,” said graduate student Carla Campos Morales.
The lesson, it seems, is that a cleaner world is within reach, but a healthier, more just one must be built with clear eyes and a map that charts not only the carbon we must avoid, but the communities we must protect.