NOx Budget Program 2007 Progress Report
Published December 2008
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Appendix D is an Excel spreadsheet. Open it with your installed version of Excel or download a free copy of the Microsoft Excel viewer
- 2007 Progress Report (PDF) (68 pp., 9.8 MB)
- Appendix D (Excel, 1.5 MB)
- Interactive Mapping
- News Brief
- Read a summary of the results of the NBP taken from the report, below
The NOx Budget Trading Program (NBP) is a market-based cap and trade program created to reduce the regional transport of emissions of nitrogen oxides (NOx) from power plants and other large combustion sources that contribute to ozone nonattainment in the eastern United States. NOx is a major precursor to the formation of ground-level ozone, a pervasive air pollution problem - also known as "smog" - in many areas in the East. The NBP was designed to reduce NOx emissions during the warm summer months, referred to as the ozone season, when ground-level ozone concentrations are highest. This report evaluates progress under the NBP in 2007 by examining emission reductions, reviewing compliance results and market activity, and comparing changes in emissions to changes in ozone concentrations.
Emissions
Since the program began in 2003, the NBP has successfully reduced ozone season NOx emissions throughout the region. In 2007, NBP ozone season NOx emissions totaled approximately 506,000 tons and were:
- 5 percent below the emission cap, despite a 3 percent increase in heat input.
- 60 percent lower than in 2000 (before implementation of the NBP).
- 74 percent lower than in 1990 (before implementation of the Clean Air Act Amendments).
Compliance
Through a wide range of pollution control strategies, sources achieved over 99 percent compliance:
- There were 2,594 units affected under the NBP in 2007. Twelve units at 11 separate NBP sources did not hold sufficient allowances to cover their emissions. Only one unit was more than 10 allowances short.
- 2007 is the fifth year of the NBP, and the fourth year in which sources achieved more emission reductions than required under the program.
Allowance Market
There was an active allowance market in 2007:
- Overall, allowance prices appear to be leveling out as prices approach the operating costs of selective catalytic reduction (SCR), a NOx control technology.
- Trading has slowed but the allowance bank continues to grow.
Ozone
Ground-level ozone has decreased since implementation of the NBP in 2003:
- Meteorologically-adjusted* seasonal 8-hour ozone levels in the NBP region have fallen by 10 percent between 2002 (before the NBP) and 2007.
- Additional analyses using different metrics have reported similar results, with average ozone reductions ranging from 8 to 11 percent in the NBP region since implementation of the program.
- A case study highlighting research by the Maryland Department of the Environment shows how ozone air quality in Maryland has improved dramatically since implementation of the NBP.
* Meteorologically-adjusted ozone refers to ozone concentration data that has been adjusted to account for the relationship between ozone and weather-related information such as temperature and humidity.
Nonattainment Areas
Based on 2005-2007 air monitoring data, ozone air quality improved in almost all of the 104 areas in the eastern United States designated to be in nonattainment for the 1997 8-hour National Ambient Air Quality Standard (NAAQS) (see map).
- Furthermore, 64 percent of these areas (67 areas) now have air quality that is better than the level of the standard. The NBP is the most significant contributor to these improvements.
- There is a strong association between areas with the greatest reductions in NOx emissions and downwind sites exhibiting the greatest improvements in ozone.
Clean Air Interstate Rule (CAIR)
Federal and state efforts to reduce ozone are ongoing in the East.
- Several federal mobile source programs will continue the progress demonstrated by the NBP. CAIR would further control emissions to reduce both ozone and fine particles in 28 eastern states and the District of Columbia.
- On July 11, 2008, the U.S. Court of Appeals for the District of Columbia Circuit (DC Circuit) issued a ruling vacating CAIR in its entirety. On September 24, 2008, EPA filed a petition for rehearing of the court decision and will determine an appropriate future course of action once the court responds to the petition. In the meantime, EPA is working with states to continue the NBP if the CAIR program is not in effect by May 2009.
| Changes in 8-Hour Ozone Nonattainment Areas in the East, 2001-2003 (Original Designations) Versus 2005-2007 | Ozone Season NOx Emissions from All NBP Sources | |
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Please see the report for more detailed information or higher resolution images
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