What Can Cleaner Air During the Pandemic Reveal About the Future Electric Power System?

The pandemic offers a unique opportunity to examine how potential future changes in the energy system can improve air quality and health.

By Michael Matz

In the months following the onset of the coronavirus pandemic, there has been significant media coverage of reductions in urban air pollution. Numerous researchers have supported this observation with air quality data. For example, National Aeronautics and Space Administration (NASA) satellite data indicate that in March 2020, nitrogen dioxide (NO₂) levels in Northeast U.S. urban areas were 30% lower than in March during the previous five years.

“NO₂ is one of the easiest air pollutants to monitor from space and is a good indicator of fossil fuel combustion in vehicles and power plants,” said Bryan Duncan, an atmospheric scientist at NASA. “Researchers may be able to use NO₂ levels to track the pandemic’s impacts on carbon dioxide levels, because the two pollutants are typically emitted together.”

Duncan was one of several air quality experts presenting at a recent EPRI-facilitated webcast for electric power industry stakeholders on the pandemic’s air quality impacts. Nearly 150 utility staff attended. It is one of an extensive series of EPRI webcasts aimed at sharing pandemic-related experiences, knowledge, and insights relevant to the power industry.

According to Melissa Lunden, chief scientist at Aclima, an analysis of air quality data revealed dramatic reductions in several air pollutants in the San Francisco Bay Area during the last two weeks of March 2020 relative to the same period in the previous three years:

• Carbon Monoxide: -15%
• Fine particulate matter (also known as PM_2.5): -30%
• NO₂: -25%
• Black carbon: -39%

These remarkable numbers prompt intriguing research questions with important implications for the power industry’s future: To what extent have broad societal changes during the pandemic—such as reduced use of gasoline-powered vehicles, closure of commercial and industrial facilities, and changes to electricity demand—reduced emissions of air pollutants, and what are the resulting health benefits? How can the answer to that question help researchers forecast air quality and health improvements as a result of widespread deployment of renewable energy and electric vehicles in the coming years?

“This period offers a unique opportunity to examine how potential future changes in the energy system can improve air quality and health,” said Eladio Knipping, an EPRI expert on air quality and atmospheric modeling. “It’s a real-world, real-time experiment.”

EPRI is launching research to investigate how the pandemic has impacted emissions and air quality. EPRI will quantify air pollutant contributions from the transportation, power generation, and industrial sectors before and during the pandemic. According to EPRI’s Knipping, the analysis will use receptor modeling and artificial intelligence techniques, drawing on data from existing networks of air quality monitoring stations across the United States.

Researchers also will evaluate meteorological data to remove the effects of weather on air pollutant concentrations. This is an important step because rainfall, temperature, wind, and other weather factors can significantly affect concentrations.

“While reducing emissions is the only way to reach our clean air goals, pollutant concentrations can fluctuate by 90% or more from day to day as a result of weather even when emissions remain constant,” said Scott Epstein, who leads the Air Quality Assessment Group at the South Coast Air Quality Management District in Southern California.

“Understanding the drivers of improved air quality during this pandemic can help us predict emissions reductions in the future energy system,” said Knipping. “These insights can inform utilities’ electrification strategies.”

A subsequent research phase will characterize the health benefits associated with reduced air pollution.

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