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Emergency Generator Emissions Calculator - Diesel CO2, Local Pollutants & RICE/NSPS Review Flags

Calculate emergency and non-emergency generator emissions with EPA tier standards and RICE NESHAP hour limits

Screen stationary diesel generator runtime and fuel use with EIA-sourced CO2, local NOx, CO, PM, and SOx placeholder rows, and RICE NESHAP / NSPS Subpart IIII source-pointer warnings. Enter kW rating, a diesel fuel-rate estimate or manual gal/hr value, annual emergency hours, maintenance/testing hours, demand-response hours, and a local tier multiplier. The output is a planning worksheet only, not a RICE NESHAP compliance determination, AP-42 factor reproduction, permit application, PTE calculation, or certified engine emission value.

Pro Tip: Use this as an early source-aware worksheet. Before regulated use, replace the local fuel-rate and pollutant placeholders with manufacturer engine data, permit factors, current AP-42 row review, source-test or CEMS data, fuel sulfur records, current eCFR rule text, state/local requirements, and qualified environmental review.

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Emergency Generator Emissions Calculator

How It Works

  1. Enter Diesel Generator Inputs

    Input generator kW, choose the local tier multiplier row, and either use the local full-load fuel-rate estimate or enter a measured/manufacturer gal/hr value.

  2. Separate Runtime Categories

    Enter annual emergency, maintenance/testing, and demand-response hours separately so the worksheet can show 100-hour and 50-hour review flags.

  3. Review Fuel and CO2 Output

    Check annual diesel gallons and CO2 based on the EIA diesel/distillate source pointer. Regulated reporting may require EPA GHG Hub, 40 CFR Part 98, permit, or program-specific methods.

  4. Treat Local Pollutants as Placeholders

    NOx, CO, PM, SOx, and tier comparison rows are local placeholders. Replace them with AP-42 row review, permit factors, engine certification data, source-test data, or CEMS records before regulated use.

  5. Verify Rule Applicability

    Use the RICE NESHAP and Subpart IIII links as source pointers only. Engine age, type, site status, permits, state rules, and operating categories control actual obligations.

Built For

  • Facility teams preparing a source-review packet before an environmental professional checks generator records
  • Environmental staff estimating diesel CO2 and placeholder pollutants before selecting an approved inventory method
  • Building engineers collecting runtime categories for permit and state-agency review
  • Data center or hospital teams screening multiple standby generator hour logs before formal compliance review
  • Industrial plants evaluating whether demand-response participation needs rule and permit review
  • Consultants documenting source gaps before replacing placeholder rows with approved factors

Assumptions

  • Fuel is diesel/distillate fuel; the app does not model natural gas, propane, gasoline, dual-fuel, landfill-gas, or fire-pump-specific rows.
  • CO2 uses the EIA diesel/distillate source pointer value of 22.45 lb/gal.
  • Auto fuel rate uses a local full-load planning estimate of 7 gal/hr per 100 kW.
  • NOx, CO, PM, SOx, and tier multipliers are local placeholders and are not AP-42 row-verified or certified engine values.
  • The 100-hour and 50-hour outputs are review screens, not compliance determinations.

Limitations

  • Does not determine emergency/non-emergency classification, RICE NESHAP compliance, NSPS applicability, notifications, reports, or record retention.
  • Does not calculate PTE, Title V, PSD, NSR, NNSR, synthetic-minor, HAP, GHGRP, or state inventory applicability.
  • Does not include VOC, HAPs, CH4, N2O, CO2e, PM10, PM2.5, controls, startup/shutdown, or malfunction emissions.
  • Does not verify engine certification, manufacture date, reconstruction, fuel sulfur records, permit terms, source-test data, CEMS data, or state/local rules.
  • Does not replace a qualified environmental professional or regulatory agency review.

References

  • EIA Carbon Dioxide Emissions Coefficients - diesel/distillate CO2 source pointer.
  • EPA AP-42 Chapter 3.4 - large stationary diesel engine source pointer.
  • EPA AP-42 Chapter 3.3 - industrial diesel engine source pointer.
  • 40 CFR Part 63, Subpart ZZZZ - stationary RICE NESHAP source pointer.
  • 40 CFR Part 60, Subpart IIII - stationary compression-ignition ICE NSPS source pointer.

Frequently Asked Questions

No. It shows local hour review flags and source pointers. Current 40 CFR Part 63 Subpart ZZZZ text, engine type, engine age, site HAP status, permit terms, state/local rules, records, and qualified review control compliance.
The app treats maintenance/testing plus demand-response hours as a local non-emergency review screen. It is a prompt to review current rule text and records, not proof that the engine is or is not classified as emergency.
Any demand-response or financial-arrangement runtime needs current rule, permit, state, and program review. The 50-hour number is a review flag in this worksheet, not automatic approval or automatic noncompliance.
No. The tier selector applies local placeholder multipliers to NOx, CO, and PM. Verify Subpart IIII applicability, engine-family certification, manufacturer data, aftertreatment status, permit factors, and current AP-42 guidance before using any tier-related output.
CO2 uses the EIA diesel/distillate source pointer value of 22.45 lb CO2 per gallon. NOx, CO, PM, and SOx remain local planning placeholders until an approved factor, permit method, source test, CEMS record, or AP-42 row review is selected.
Not by itself. Treat it as a worksheet for organizing runtime, fuel, and source-gap questions. Use the method required by the permit, state agency, 40 CFR Part 98, AP-42, source-test/CEMS records, or qualified environmental professional.
Disclaimer: This planning screen provides preliminary diesel-generator arithmetic and source pointers only. It is not regulatory compliance advice, a RICE NESHAP or NSPS determination, an AP-42 table reproduction, a permit application, a PTE calculation, or a substitute for state-agency, permit, engine-manufacturer, source-test/CEMS, fuel-record, and qualified environmental review.

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