Potential Seen to Reduce Air Pollutants by 750K Tons

Great follow up to our story on Obama's recent push to clean up power plants and shift the types of energy that grids buy and deliver to customers:

By ecoRI News staff

Setting strong standards for climate-changing carbon emissions from power plants would provide an added bonus: reductions in other air pollutants that can make people sick, damage forests, crops and lakes, and harm fish and wildlife, according to a recently released study by Harvard and Syracuse University scientists

The authors mapped the potential environmental and human-health benefits of power plant carbon standards using three policy options for the forthcoming Environmental Protection Agency (EPA) rule as a guide to model changes in power plant emissions of four other air pollutants: fine particulate matter; nitrogen oxides; sulfur dioxide and mercury. The scientists compared the model results with a business-as-usual reference case for the year 2020.

Of the three scenarios simulated in the study, the top-performing option decreased sulfur dioxide and mercury emissions by 27 percent and nitrogen oxide emissions by 22 percent by 2020 compared to the reference case. This option reduced carbon dioxide emissions from the power sector by 35 percent from 2005 levels by 2020.

The resulting air-quality improvements are likely to lead to significant gains in public and environmental health, according to the study.

“When power plants limit carbon dioxide emissions, they can also release less sulfur dioxide, nitrogen oxide and other pollutants,” said Charles Driscoll, Ph.D., of Syracuse University. “One of the policy options we analyzed cut emissions of these non-carbon pollutants by approximately 775,000 tons per year by 2020. We know that these other pollutants contribute to increased risk of premature death and heart attacks, as well as increased incidence and severity of asthma. They also contribute to acid rain, ozone damage to trees and crops, and the accumulation of toxic mercury in fish.”

In addition to summarizing changes in emissions, the study quantifies the resulting improvements in air quality. With a strong carbon standard, improvements are widespread and every state receives some benefit, according to the study. The maps show that the greatest benefits occur in the eastern United States, particularly in states in and around the Ohio River Valley, and in the Rocky Mountain region.

States that are projected to benefit from the largest average decreases in fine particle pollution and summer ozone pollution detrimental to human health include: Ohio, Pennsylvania, Maryland, West Virginia, Illinois, Kentucky, Missouri, Indiana, Arkansas, Colorado and Alabama.

States that are projected to benefit from the largest average decreases in sulfur and nitrogen pollution detrimental to ecosystems include: Pennsylvania, West Virginia, Ohio, Maryland, Kentucky, Delaware, Indiana, Illinois and Missouri.

Most other states see improvements in both air quality and atmospheric deposition of pollutants that vary state to state. The findings also show that different policy options yield different outcomes. The detailed air quality modeling makes it clear that a modest rule limited to making power plant improvements  “inside the fence,” similar to what some industry groups have proposed, would bring little if any air-quality benefits, according to the study.

“Our analysis demonstrates that strong carbon standards could also have widespread benefits to air quality and public health,” said Dr. Jonathan Buonocore of the Harvard School of Public Health. “With a mix of stringency and flexibility, the new EPA rules have the potential to substantially reduce emissions of sulfur dioxide and nitrogen oxides from power plants, which contribute to local and regional air pollution. This is an opportunity to both mitigate climate change and protect public health.”