The impact of improved temporal profiles for point sources on air quality
A. Unal1, N. Lahoti2, R. Papalski3, and P.G. Georgopoulos2
1MACTEC, Trenton, NJ; 2Environmental and Occupational Health Sciences Institute, UMDNJ - R.W. Johnson Medical School and Rutgers University, Piscataway, NJ; 3New Jersey Department of Environmental Protection (NJDEP), Trenton, NJ
Electric Generating Units (EGUs) are one of the highest contributors of air pollutants, especially for NO X and SO 2 . Under certain conditions their impact on air quality, both ozone and PM2.5, might be significant. Identification and quantification of uncertainty in emissions estimates for these sources are essential in improving air quality model results in regulatory modeling efforts. In this study, our aim is to quantify uncertainty in EGU emissions due to temporalization. For this we have developed unit specific temporal profiles, using Continuous Emissions Monitoring (CEM) data, as well as facility specific and state specific temporal profiles for Northeastern United States . We compared these profiles with default temporal profiles used in SMOKE. This paper summarizes the findings of these comparisons at emission distribution level. We investigate the impact of utilizing unit/facility specific temporal profiles on air quality by running CMAQ with both the default and the improved temporal profiles cases respectively. In this study we also investigated temporal profiles for Peaking Units (i.e., Units used under heavy electricity demand) based upon the data from EPA's Clean Air Markets Division. Using default temporal profile for these units can cause a significant underestimation of emissions during hot days when electricity consumption peaks. This paper will present the impact of using unit specific profiles for Peaking Units on air quality as well.
This work is funded in part by a University Partnership Agreement between USEPA and EOHSI. Viewpoints expressed here are do not necessarily reflect views of the USEPA or its contractors.