eGRID2018 Notes

eGRID2018v2 Revision

eGRID2018 was originally released on January 28, 2020 and the revised version, eGRID2018v2, was released on March 9, 2020. The CH4 and N2O input emission rates (lb/MMBtu) and fuel-specific output emission rates (lb/MWh) were corrected in v2. The original 2018 eGRID version mistakenly applied a tons-to-pounds conversion factor of 2,000 to these specific CH4 and N2O rates. Columns BJ & BK on the PLNT18 sheet; AE & AF and BF through BM on the ST18, BA18, SRL18, and NRL18 sheets; and AC & AD and BD through BK on the US18 sheet were revised. No other data changes were made and the summary tables remained the same.

What are the EIA-923 data updates reflected in eGRID2018?

The 2018 EIA-923 data were originally released on September 20, 2019.  Subsequently, the Energy Information Administration (EIA) released several revisions to the EIA-923 data. eGRID2018v2 is based on the November 21, 2019 revision to EIA-923 data. Following the release of eGRID2018v2, EIA has released at least 5 additional updates, including a March 5, 2020 release which, among other corrections, revised the Meramec power plant and Plant 31 Paper Mill's data.

Meramec

The annual generation data for the Meramec power plant (ORIS ID 2104) from -2,313,523 MWh to +1,346,084 MWh. This change in generation leads to a small shift in the overall output emission rates for the state of Missouri, the MISO balancing authority, the SRMW eGRID subregion, and the SERC NERC region. While the change in eGRID2018v2 emissions and emission rates was not deemed significant enough to release an updated eGRID2018 version (the change was less than 5%), the table below presents the eGRID2018v2 and revised (based on the March 5, 2020 EIA-923 release) CO2 output emission rates. This  presents the CO2, as well as, the CH4, N2O, CO2e, NOX annual, NOX ozone season, and SO2 output emission rates at the plant, state, BA, eGRID subregion, NERC region, and US level that were affected by this change.

Plant 31 Paper Mill

Another correction to the EIA 923 data involved two changes for Plant 31 Paper Mill in Louisiana (ORIS ID 50028), including (1) a substantial reduction in fuel consumption of black liquor (from 108,095,474 MMBtu to 9,004,793 MMBtu), and (2) an increase in fuel consumption for electricity generation from natural gas (from 146,196 MMBtu to 932,669 MMBtu). The total net generation at this plant was not changed with these corrections.

Because the eGRID biomass adjustment zeros out all emissions from black liquor at the plant level, the large decrease in black liquor consumption at this plant does not actually result in a decrease in the adjusted eGRID plant-level emissions.

The increase in natural gas consumption for this plant does result in an overall net increase in emissions and fuel consumption at the plant level, as shown in the table below. This increase has a negligible (<0.01%) impact on the state-level rates for Louisiana or the subregion-level rates for SRMV.