Electrification’s Impact on CO2 and Air Quality

Electrification is a cornerstone in many economy-wide decarbonization plans. Driven by policy, technology, and consumer choice, there are expanding opportunities for electric end-use technologies in the building, industrial, and transport sectors. While studies have shown how electrification in these areas can help advance decarbonization goals, there is still much to learn about the impacts on air quality. Better understanding how electrification affects air quality (and consequently human health) has large implications for policymakers, as well as energy system planners. To advance this understanding, EPRI led research with collaborators from Ramboll and Oak Ridge National Laboratory to provide an economy-wide evaluation of CO2 and, the positive, air quality implications of electrification in the United States. Our findings were published this week in a new article in Nature Communications. 

Our study was unique for several reasons. First, we used an integrated electric and energy system model – EPRI’s U.S. Regional Economy, GHG, and Energy (US-REGEN) framework – which captures temporal, spatial, sectoral, and technological detail. This allowed us to simulate electricity demand in a range of scenarios and with increasing degrees of electrification. This detailed energy systems model was then linked to a full-form photochemical modeling system for gas and particulate air pollution. Using the Comprehensive Air Quality Model with Extension (CAMx) with US-REGEN provided an integrated approach that leverages the current state-of-science for the most comprehensive and detailed understanding possible. 

Our research considered three scenarios: 

• Limited Electrification: Limited electric vehicle (EV) adoption, no growth in building electrification, and no concerted federal climate policy. These assumptions lead to a relatively flat electricity demand over time and provided a baseline scenario with which to compare scenarios with higher degrees of electrification. 
• High Electrification without Carbon Price: More optimistic assumptions about electrified end-use technology adoption but does not include national CO2 policies. Higher electrification in this scenario is driven by widespread adoption of EVs and heat pumps. We believe this scenario more closely reflects expected market trends.
• High Electrification with Carbon Price: Following the same technology adoption assumptions as the previous scenario, this scenario introduces a carbon price starting in 2025 at $50/tCO2 (in 2020 USD) and growing at 7 percent per year (reaching $271/tCO2 in 2050). Carbon pricing in this scenario is a proxy for a suite of policies and incentives to encourage economy-wide decarbonization, including greater emissions reductions in the power sector. 

When modeling these three scenarios in our integrated energy system and air quality framework, the results were clear - electrification lowers CO2 and improves air quality. These air quality benefits are immediate and localized and can be amplified through decarbonization policies. We also show that commonly used short-run marginal emissions approaches significantly underestimate reductions from electrification, ranging from 32 to 91 percent. 

Electrification can lead to substantial improvements in ozone, though this benefit varies by location. Our research shows that electrification also lowers fine particulate matter. Adding carbon pricing further lowers ambient values, though growing economic activity could increase emissions from categories such as road dust, industrial facilities, and agriculture. But even small improvements in fine particulate matter can have large health benefits. And, again, these effects are felt immediately and locally which is in contrast to the effects of reducing climate damages, which may take decades to be felt and occur in geographically distant locations. 

If you are interested in learning more about this research and our findings, we invite you to read the full article “Economy-wide Evaluation of CO2 and Air Quality Impacts of Electrification in the United States” published in Nature Communications. We’ve also prepared a two-page research brief to highlight key findings. You can find this and more information on EPRI’s decarbonization research, including recent studies applying REGEN, on EPRI.com.