Breathing easier: Cap and trade lowers smog levels in eastern United States
More than 102 million Americans are breathing cleaner air due to decreases in smog-forming emissions of nitrogen oxides (NOx) according to the NOx Budget Trading Program annual report. The 2007 summertime NOx emissions from power plants and industrial sources were down by 60 percent compared to 2000 levels and 74 percent below 1990 levels in 20 eastern states and the District of Columbia.
The program helped improve air quality in 95 percent of nonattainment areas in the east, with 64 percent of these areas now below the ozone standard. Some of the report highlights show that:
- the largest NOx emission reductions occurred in Ohio, Indiana, Illinois, West Virginia, and Kentucky; and
- the reduction of NOx – a precursor to ground-level ozone, or smog – has helped reduce ozone concentrations an average of 10 percent in the eastern part of the country since the start of the program in 2003.
The program is a market-based cap and trade partnership between federal and state governments to reduce the regional transport of NOx during the ozone season. The program provides facilities flexibility to choose their control options including installing control technologies, optimizing existing controls, and switching fuels. Stringent monitoring, reporting and automatic penalties have led to a compliance rate of over 99 percent.
EPA, state and local programs have contributed to the decrease in NOx and ozone levels since 1990. The program has contributed the most to improvements in ozone levels since 2003.