GHG Rollup Requirements

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"Rollups" are aggregated GHG emissions. Rollups are automatically calculated by e-GGRT according to requirements of Subpart A--General Provisions and cannot be overridden by reporters.

To support rollups user are required to use the following conventions for the reporting of numeric values:

Number Format

Description

 

 

 

Rounding

  • CO2e, CO2, N2O, and CH4 emission data expressed in metric tons will be rounded as follows: 
    a) CO2 and CO2e: metric ton and short ton values entered by the user are rounded to 1 place to the right 
    of the decimal 
    b) CH4: metric ton values entered by the user are rounded to 2 places to the right of the decimal, 
    c) N2O: metric ton values entered by the user are rounded to 3 places to the right of the decimal, and 
    d) All other GHGs: metric ton values entered by the user are rounded to 4 places to the right of the decimal
  • This will be done regardless of the level of data collection (e.g., unit-level, facility-level, etc.) This rounding 
    would be applied to a value in each of the following cases: a) An emissions value that has been entered 
    directly by the user because e-GGRT does not provide automated calculation support for the method 
    described in the rule (e.g., Tier 4 emissions) and b) An emissions value that is automatically calculated 
    by the system and an ‘override’ value has not been entered and C) an emissions value is an ‘override’ value.
  • Emissions data for all GHGs other than CO2, N2O, and CH4 expressed in metric tons will be rounded 
    to the fourth digit to the right of the decimal (one tenth of a kilogram, or 1 ten thousandth of a metric ton). 
    This rounding would be applied as described above (see cases 2(a), 2(b), and 2(c) and applied regardless 
    of the level of data collection (unit, facility, etc.)),  Reporting of GHGs other than CO2, N2O, and CH4 
    is limited to Subparts F, O, and OO.
  • Other quantitative data calculated by the system (e.g., annual average HHV values, facility-specific 
    emission factors) will be rounded as specified in the requirements document, if at all. In some cases, 
    e-GGRT may round a value only for the purposes of displaying it as a read-only value.
  • Other (non-emissions) quantitative data entered by the user that is not the result of a system calculation 
    (e.g., a monthly HHV sample result, an annual production quantity, etc.) would not be rounded. In some 
    cases, e-GGRT may round a value only for the purposes of displaying it as a read-only value.
  • All rounding (JAVA, JavaScript, Oracle) would apply the standard, identical rounding conventions 
    whereby 0.5 is rounded up (23.5 is rounded to 24; 23.499999 is rounded to 23).
  • The database schema would store both the rounded and unrounded results. Only rounded results 
    would be included in annual GHG reports.
  • The XML schema will only include rounded results.
  • In the case of aggregation/roll-ups, those calculations will be performed on the rounded values.
PercentagesIf a value is reported as a percentage, then the number should be within the range of 0 to 100 (percent). 
For example, 85.5% is reported as 85.5.
FractionsIf a value must be reported as a decimal fraction, then the number should be within the range of 0 and 1 
(e.g., 1/4 should be reported as 0.25). Leading zeroes are optional.

 

For source categories (also referred to as "facility subparts" - subparts C-II, SS, and TT), section 98.3(c)(4) requires the following rollup calculations:

  • Annual emissions (excluding biogenic CO2) aggregated for all GHGs from all applicable source categories, expressed in metric tons of CO2e calculated using Equation A–1.
  • Annual emissions of biogenic CO2 aggregated for all applicable source categories, expressed in metric tons.
  • Annual emissions from each applicable source category, expressed in metric tons of each applicable GHG listed below:
    • Biogenic CO2
    • CO2 (excluding biogenic CO2)
    • CH4
    • N2O
    • Each fluorinated GHG (including those not listed in Table A–1)

These e-GGRT rollup requirements for source categories displayed in the diagram below:

e-GGRT Rollup Requirements for Source Categories Diagram

For supplier categories (also referred to as "supplier subparts" - subparts LL-QQ), section 98.3(c)(5) requires the following rollup calculations:

  • Total quantity of emissions aggregated for all GHG (excluding biogenic CO2 and fluorinated GHGs that are not found in Table A-1) from all applicable supply categories in Table A–5, expressed in metric tons of CO2e and calculated using Equation A–1.
  • Quantity of CO2, CH4, N2O, and each fluorinated GHG (as defined in §98.6), including those not listed in Table A–1 from each applicable supply category in Table A–5, expressed in metric tons of each GHG. For fluorinated GHG, report emissions of all fluorinated GHG, including those not listed in Table A–1 of this subpart. For fluorinated GHGs, calculate and report CO2e for only those fluorinated GHGs listed in Table A–1.

These e-GGRT rollup requirements for supplier categories displayed in the diagram below:

e-GGRT Rollup Requirements for Supplier Categories Diagram

To view the emissions rollup for your facility or supplier, click the VIEW GHG DETAILS button in the blue panel at the upper right of the Facility or Supplier Overview page.

Click the VIEW GHG DETAILS button to view the emissions rollup for facility or supplier

Underneath each results column, you may also click on the "Edit result(s)" link to add your own subpart-level emissions results.

Click the Edit Results link to add subpart-level emissions results

After entering your results, click SAVE. You will be returned to the "GHG Quantity Details" page. Your entered results will show up as blue in the table while those calculated by e-GGRT will be black.

Click the SAVE button after entering results and return to the GHG Quantity Details page