A new study reveals that setting strong standards for climate-changing carbon emissions from power plants would also result in reduction in other air pollutants harmful to human beings and environments.
The study, “Co-benefits of Carbon Standards: Air Pollution Changes under Different 111d Options for Existing Power Plants,” by scientists at Syracuse University and Harvard use three policy options for the forthcoming EPA rule as a guide to model changes in power plant emissions of four other harmful air pollutants: fine particulate matter, nitrogen oxides, sulfur dioxide, and mercury. The results were compared with a reference case for the year 2020.
Of the three scenarios simulated, 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.
According to scientists the resulting air quality improvements are likely to lead to significant gains in public and environmental health.
“When power plants limit carbon dioxide emissions, they can also release less sulfur dioxide, nitrogen oxide and other pollutants,” said Dr. Charles Driscoll of Syracuse University. “One of the policy options we analyzed cut emissions of these non-carbon pollutants by approximately 75,000 tons per year by 2020,” Driscoll said.
The study shows that there is real opportunity to help reverse decades of environmental damage from power plant emissions and to improve human health, Driscoll said.
With a strong carbon standard, improvements are widespread, and every state receives some benefit. The maps show that the greatest benefits occur in the eastern U.S., particularly in states in and around the Ohio River Valley, as well as the Rocky Mountain region.
States that are projected to benefit from the largest average decreases in fine particle pollution (PM2.5) and summer ozone pollution detrimental to human health include Ohio, Pennsylvania, Maryland, West Virginia, Illinois, Kentucky,Missouri, Indiana, Arkansas, Colorado, and Alabama (based on the top 6 states for each pollutant).
States that are projected to benefit from the largest average decreases in sulfur and nitrogen pollution detrimental to ecosystems include: Pennsylvania, Wes Virginia, Ohio, Maryland, Kentucky, Delaware, Indiana, Illinois, and Missouri (based on the top 6 states for each pollutant).
Most other states see improvements in both air quality and atmospheric deposition of pollutants which vary state to state.
“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 at Harvard University.
“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,” Buonocore added.
The U.S. EPA is expected to release its proposed rules for carbon pollution from existing power plants June 2.