Reported production CO2 by plant

Period

2023–2024

One row is

published plant x EPA reporting year, monitored units summed

Built from source rows of

EPA emissions unit x hour (local standard time; the reporting year is the local calendar year), reporting years 2023 and 2024, Washington, Oregon, Idaho and Montana

Evidence and method

metered · directContinuous emissions monitoring of units EPA's programs cover: fossil units serving generators above 25 MW, with exemptions for pre-1990 simple-cycle turbines, qualifying cogenerators and units of 25 MW or less. CO2 mass is in short tons as filed; gross load is the unit's own hourly MW, which need not include a combined-cycle steam turbine; an hour flagged Substitute or Measured and Substitute follows Part 75 missing-data procedures rather than a monitor reading. A plant without rows here is unmonitored, not zero.

Origin

U.S. EPA Clean Air Markets Division, Power Sector Emissions Data reported under 40 CFR Part 75: hourly CO2 mass, gross load, heat input and operating time of each monitored emissions unit, with EPA's measured/substitute flag ↗Source notice and licenceLicence: CC-BY-4.0

Built from source rows of

EPA emissions unit x EIA generator (x boiler) x report year

Evidence and method

reported · derivedA steam turbine of a combined-cycle plant is linked to each of its combustion turbines' units and counts once as a monitored generator. PUDL removes unmatched rows, so a crosswalk unit with no CEMS rows in the year is a unit that did not report, not a match failure.

Origin

EPA-EIA Power Sector Data Crosswalk (PUDL's fork, run on each year of EIA-860): EPA emissions unit to EIA plant, boiler and generator ↗Source notice and licenceLicence: CC-BY-4.0

Built from source rows of

generator x report_date (annual)

Evidence and method

reported · derived

Origin

U.S. EIA Form 860 (mix of EIA forms, harvested) ↗Source notice and licenceLicence: CC-BY-4.0

Edition in this release

PUDL v2026.9.0 (embedded 2026.8.1.dev50) · out_eia__yearly_generators · retrieved 2026-09-29PUDL v2026.9.0 (embedded 2026.8.1.dev50) · core_epacems__hourly_emissions · retrieved 2026-09-29PUDL v2026.9.0 (embedded 2026.8.1.dev50) · core_epa__assn_eia_epacamd · retrieved 2026-09-29

Download

emissions_plant_year.parquet ↓58 rows · 12 KBemissions_unit_year.parquet ↓100 rows · 10 KB

• Eligible plantspublished plants with an existing coal, gas, oil or waste generator in the inventory year; EPA's programs monitor fossil units serving generators above 25 MW
  107 plants
• Listed in 202376 plants eligible and not listed
  29 of 107 plants27.1% of eligible
• Listed in 202478 plants eligible and not listed
  29 of 107 plants27.1% of eligible

• Listed without a reported valueListed for the year with no co2 mass value on any row; published as null with quality missing
  0 plant-years
• Only some units monitoredListed plants where some existing combustion generator links to no monitored unit: the mass is the monitored units' alone, not the plant's total, and no intensity is computed
  4 plant-years
• In the source, not yet includedCEMS reporting years other than those acquired; EPA and PUDL hold hourly data from 1995
  Not computedan EPA CEMS slice beyond the acquired reporting years is not part of this build
• No row in the sourcePublished plants with an existing coal, gas, oil or waste generator in the inventory year and no CEMS row for that year: unmonitored under EPA's programs (pre-1990 simple-cycle turbines, qualifying cogenerators and units of 25 MW or less are exempt). The plant burns fuel and its CO2 is not zero; it is not reported here. Each reporting year is set against its own inventory: 2023–2024
  154 plant-years
• Not applicablePublished plants with no coal, gas, oil or waste generator in the inventory year: no combustion unit for EPA to monitor, which is not a claim of zero emissions: 2024
  648 plants
• Outside the atlas framePlants with CEMS rows in the acquired slice that the atlas does not publish: outside the frame authorities and the core states
  0 plants

Publisher

Units report hourly emissions and operating data to EPA within 30 days of the end of each calendar quarter, per CAMD's Power Sector Emissions Data Guide; PUDL's source page states that EPA releases the hourly data quarterly, with a lag of two to three months.www.epa.gov/system/files/documents/2022-07/CAMD%27s%20Power%20Sector%20Emissions%20Data%20Guide%20-%2007182022.pdf ↗docs.catalyst.coop/pudl/en/v2026.9.0/data_sources/epacems.html ↗

Delay

EPA's Power Sector Data page states no release schedule (page last updated April 2, 2026). PUDL's source page states a lag of two to three months after each quarter, lists temporal coverage 1995q1 to 2026q2 for the pinned version, and updates the data on PUDL's quarterly schedule.www.epa.gov/power-sector/power-sector-data ↗docs.catalyst.coop/pudl/en/v2026.9.0/data_sources/epacems.html ↗

This atlas

The atlas reads reporting years 2023 and 2024 for Washington, Oregon, Idaho and Montana as a registry slice of PUDL's hourly CEMS table, named under edition; the table changes only when the PUDL pin moves or the slice widens. No timed refresh.docs.catalyst.coop/pudl/en/v2026.9.0/data_access.html ↗

• keys.emissions_plant_unique{"distinct":58,"rows":58}
  Passed
• keys.emissions_unit_unique{"distinct":100,"rows":100}
  Passed
• emissions.monitored_within_plant_units{"partly_monitored_plants_with_an_intensity":0,"plants_flagged_complete_without_full_link":0,"plants_with_more_monitored_than_combustion_generators":0,"plants_with_unknown_flag":0}
  Passed
• emissions.measurement_hours_reconcile{"plants_with_unreconciled_hours":0}
  Passed
• emissions.hours_within_year{"hours_in_year":{"2023":8760,"2024":8784},"plants_with_operation_hours_over_year":0,"units_listing_more_hours_than_the_year":0,"units_operating_more_than_listed":0}
  Passed
• emissions.values_non_negative{"units_negative":{"co2_mass_short_tons":0,"gross_load_mwh":0,"heat_input_mmbtu":0}}
  Passed
• emissions.crosswalk_unit_single_plant{"units_under_two_eia_plants_in_cems":0,"units_under_two_eia_plants_in_crosswalk":0}
  Passed
• emissions.gross_load_below_net_generation{"plants_compared":58,"plants_with_gross_below_net":9}
  Passed

No corrections apply to this dataset in this release. Earlier editions: not available (earlier releases did not retain per-dataset edition comparisons).