Appendix H 

Emissions Modeling 

Deviation From Defaults 
Emissions Modeling Deviation from Defaults i 

The Charlotte-Gastonia-Rock Hill, NC-SC 8-Hour Ozone Appendix H 

North Carolina Attainment Demonstration June 15, 2007 
Emissions Modeling Deviation from Defaults ii 

The Charlotte-Gastonia-Rock Hill, NC-SC 8-Hour Ozone Appendix H 

North Carolina Attainment Demonstration June 15, 2007 

Table Of Contents 

1 Introduction................................................................................................................................. 1 

1 Deviation From Everyday Modeling .......................................................................................... 1 

2 Point Source Deviation ............................................................................................................... 2 

List Of Tables 

Table1. Representative Time Period for Emissions Modeling ...................................................... 2 

Table 2. Comparison of 2009 emissions for Duke and Progress compliance plans vs. IPM. ....... 3 
Emissions Modeling Deviation from Defaults iii 

The Charlotte-Gastonia-Rock Hill, NC-SC 8-Hour Ozone Appendix H 

North Carolina Attainment Demonstration June 15, 2007 
Emissions Modeling Deviation from Defaults 1 

The Charlotte-Gastonia-Rock Hill, NC-SC 8-Hour Ozone Appendix H 

North Carolina Attainment Demonstration June 15, 2007 

1 Introduction 

The emissions modeling for the Charlotte-Gastonia-Rock Hill, NC-SC 8-hour ozone 

nonattainment area was performed in conjunction with the regional haze modeling being done by 

the Southeast Regional Planning Organization, Visibility Improvement State and Tribal 

Association of the Southeast (VISTAS) and the fine particulate matter (PM2.5) and ozone 

modeling being done by the Association of Southeastern Integrated Planning (ASIP). VISTAS 

and ASIP are run by the ten Southeast states (Alabama, Florida, Georgia, Kentucky, Mississippi, 

North Carolina, South Carolina, Tennessee, Virginia and West Virginia. The emissions 

preprocessing model used to ready the emissions for input into the air quality model was the 

Spare Matrix Operator Kernel Emissions (SMOKE) modeling system. 

1 Deviation From Everyday Modeling

The VISTAS/ASIP modeling was an annual simulation. It would be too resource intensive to 

process all sources sectors for everyday of the year. Therefore, to produce an emissions 

inventory to support the annual modeling, representative time periods were selected and 

modeled. 

The area and nonroad mobile sources were modeled as a block of Thursday, Friday, Saturday, 

Sunday, Monday, one per month (total of 60 days modeled for the annual simulation). Similarly, 

the on-road mobile sources were represented by an entire single week for each month. This 

selection criteria allows for the representation of day-of-the-week variability in the on-road 

motor vehicles, and models a representation of the meteorological variability in each month. 

The stationary point sources, which include the electric generating units (EGUs) and Non-EGUs, 

were modeled everyday of the annual simulation. This was due to the plume rise calculations 

used to parse the emissions into the various layers of the model is different everyday depending 

on the meteorological inputs. Additionally, VISTAS/ASIP modeled large wildland fires as day 

specific sources with plume rise incorporated into the emissions modeling. Similar to the 

stationary point sources, the biogenic emissions were modeled everyday of the annual simulation 

since the amount of volatile organic compounds emitted is significantly impacted by temperature 

and solar radiation. 

For the area, nonroad mobile and on-road mobile sources, the holidays were modeled as a 

Sunday. Table 1 describes the representative time period for all source categories. 
Emissions Modeling Deviation from Defaults 2 

The Charlotte-Gastonia-Rock Hill, NC-SC 8-Hour Ozone Appendix H 

North Carolina Attainment Demonstration June 15, 2007 

Table1. Representative Time Period for Emissions Modeling 

Source Category BaseG frequency of run 

Area Sources 5 days per month 

Biogenic Everyday 

Canada_area 5 days per month 

Canada_point 5 days per month 

Dust 5 days per month 

EGU Everyday 

Fire_cenrap Everyday 

Hi_file_typ Everyday 

Lo_file_typ 5 days per month 

Mexico_area 5 days per month 

Mexico_point 5 days per month 

mms_area 5 days per month 

mms_point Everyday 

Non-EGU Everyday 

Nonroad Mobile 5 days per month 

On-road Mobile 7 days per month 

2 Point Source Deviation 

The VISTAS/ASIP emissions modeling used results from the Integrated Planning Model (IPM) 

to generate future year emissions for the EGU source sector. Duke Energy and Progress Energy 

updated their plans for complying with North Carolina’s Clean Smokestacks Act and the 

emission projections for the plans varied substantially from the IPM results (Table 2). Therefore, 

the North Carolina Division of Air Quality (NCDAQ) replaced the IPM emission projections for 

2009 with projections from the 2006 Duke Energy and Progress Energy compliance plans. The 

Clean Smokestacks Act can be found in Appendix M. 

Another point source deviation was the temporal profiles used for the typical emissions for the 

EGU source sector. Instead of using the 2002 continuous emissions monitoring (CEM) profiles 

for the EGUs, a typical temporal profile was created using data from 2000 through 2004. How 

the typical temporal profiles were generated is discussed in detail in Appendix F.1. 
Emissions Modeling Deviation from Defaults 3 

The Charlotte-Gastonia-Rock Hill, NC-SC 8-Hour Ozone Appendix H 

North Carolina Attainment Demonstration June 15, 2007 

Table 2. Comparison of 2009 emissions for Duke and Progress compliance plans vs. IPM. 

Facility 

Compliance Plan 

2009 NOx 

(tpy) 

IPM 

2009 NOx 

(tpy) 

Duke Energy Facilities

Allen 5,774 3,018 

Belews Creek 4,296 5,230 

Buck 1,713 1,788 

Cliffside 2,740 2,619 

Dan River 1,539 1,134 

Marshall 12,903 12,262 

Riverbend 1,944 1,989 

Total Duke Energy 30,909 28,040 

Progress Energy Facilities

Asheville 3,057 1,049 

Cape Fear 1,350 1,249 

Lee 3,110 3,901 

Mayo 1,741 1,748 

Roxboro 6,350 4,069 

Sutton 5,840 4,361 

Weatherspoon 2,822 2,239 

Total Progress Energy 24,270 18,616