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 decima, 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., amonthly HHV sample result, an annual production quantity, etc.) would not be rounded. In some cases, e-GGRTmay 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 beincluded 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.

Percentages

If 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.

Fractions

If 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:

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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:

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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.

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

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