Energy technology choices shaping the air quality and health effects of a Net-Zero transition

Transitioning to a net-zero emissions economy can provide air quality and health benefits. Yet it is still unclear how different low-carbon energy strategies influence the overall benefits and their distribution. Based on a multi-model analysis using three leading energy models for the U.S. (GCAM-USA, US-REGEN, and REPEAT), we demonstrate that a net-zero transition from now to 2050 yields robust nationwide reductions in ambient concentrations of fine particulate matter (PM2.5) and associated mortality. However, the health co-benefits achieved in the net-zero scenarios relative to business-as-usual baselines vary substantially across models and regions. These differences largely result from how mitigation efforts are allocated across sectors, especially the use of carbon dioxide removal technologies, which can relocate residual emissions across regions and, in some cases, increase local pollution levels. As pollution from non-energy activities such as wildfires continues to grow, minimizing energy-related emissions is critical to counteract potential increases in other sectors.