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singularity-energy / open-grid-emissions

Tools for producing high-quality hourly generation and emissions data for U.S. electric grids
MIT License
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Fix biomass adjustment for CEMS waste (MSW) data #51

Open grgmiller opened 2 years ago

grgmiller commented 2 years ago

Historically, any generators that burned municipal solid waste (MSW) reported this fuel consumption under a single fuel code. In recent years, however, EIA-923 began reporting these data under two separate codes for the biogenic portion (MSB) and non-biogenic portion (MSN). This is important because each portion has different emission rates. We should ensure that when this data is available, the more specific fuel codes are being used instead of MSW.

grgmiller commented 2 years ago

Currently, the EIA allocation process uses the separate fuel types when available, but when assigning fuel types to CEMS data using the power sector data crosswalk, this only includes fuel codes for MSW. However, the emissions factors for all waste fuel types (MSW, MSB, and MSN) are all the same, so this shouldn't matter.

Where this would make a difference is when we adjust the cems data for biomass emissions. Currently, any CEMS data reported as MSW does not get adjusted for biomass. One way we could fix this would be to reference the allocated EIA-923 data and calculate which fraction of fuel consumption in each month is MSB vs MSN, and use that to adjust the CEMS data.

However, I am unsure whether doing these biomass adjustments even makes sense.