How we calculate
your carbon footprint — Carbon accounting methodology
Every number in Eco-Auditor traces back to the activity data you imported, the emission factor applied, and the published dataset that factor came from. No black boxes, no mystery calculations — just transparent, reviewable carbon accounting.
Aligned with global carbon accounting standards
Eco-Auditor has been designed from the ground up to follow established GHG accounting frameworks — not proprietary black-box models. Every methodology decision is documented and auditable.
GHG Protocol Corporate Standard
Scope 1 and 2 accounting, organizational boundary setting (operational control), and base year emissions tracking.
GHG Protocol Scope 3 Standard
Corporate Value Chain (Scope 3) Standard with spend-based estimates for common Scope 3 categories.
California SB 253 / SB 261
CARB's September 2026 Guidance for SB 253 2026 Reporting says covered entities (U.S. companies doing business in California with annual revenue over $1 billion) report Scope 1 and Scope 2 for the applicable preceding fiscal year, due on or before November 10, 2026. The initial regulation had set August 10, 2026. That guidance says the Initial Regulation was still subject to Office of Administrative Law approval, so confirm the operative date on CARB's program page. Scope 3 is not part of the 2026 report. Assurance and Scope 3 timing for later years are in a separate rulemaking. The $500 million figure belongs to SB 261, not SB 253. Eco-Auditor can help assemble a GHG inventory; it does not file the report.
EU CBAM
Eco-Auditor can support the collection and organization of emissions inputs used in CBAM-related workflows. It does not replace an authorized declarant, customs filing, legal review, or required verification. Applicability depends on importer status and goods traded.
EPA GHG Inventory Guidance
Emission factor libraries from the EPA GHG Emission Factors Hub and eGRID.
Scope 1 — Direct Emissions
Sources you own or control
What's included
- Natural gas combustion in boilers and furnaces
- Company-owned vehicle fuel
- Refrigerant leakage from HVAC equipment
- On-site diesel generators
- Process emissions from manufacturing
Calculation method
Activity data (fuel bills, meter readings) × EPA emission factors. Refrigerant leakage calculated as refrigerant mass × IPCC AR5 GWP-100.
Scope 2 — Purchased Energy
Indirect emissions from electricity, steam, heat, cooling
What's included
- Purchased electricity (grid)
- Purchased steam or hot water
- Purchased cooling / chilled water
- On-site solar (net metering)
Calculation method
Location-based: kWh × eGRID subregion emission factor (lbs/MWh).
Scope 3 — Value Chain
All other indirect emissions in your value chain
What's included
- Purchased goods & services (spend-based)
- Upstream transportation & distribution
- Business travel (air, rail, hotel)
- Employee commuting
- Downstream transportation
- Waste generated in operations
Calculation method
Common Scope 3 categories via spend-based estimates applied to procurement spend data. These category-average factors are Eco-Auditor internal estimates, not a published EEIO dataset.
Data confidence
Not all data is equal. Every entry carries a confidence score so you can see which numbers rest on metered activity data and which are spend-based estimates.
Eco-Auditor data-confidence score. This score is an internal decision-support indicator — not an assurance opinion and not a GHG Protocol certification. It is assigned from the activity category and the specificity of the factor applied, or taken from a confidence column in your import file when you supply one. It is not externally standardized. A per-entry quality hierarchy, reviewer sign-off, and confidence overrides are planned, not shipped.
Metered kWh against a published eGRID subregion factor
Fuel volume against an EPA Emission Factors Hub factor
Fuel volume against an EPA Emission Factors Hub factor
Activity or spend against a category-average factor
Activity or spend against a category-average factor
Spend-based estimate against a category-average factor
Your goal: move every material emissions source off spend-based estimates and onto metered activity data before filing.
Emission factor libraries
We aggregate and maintain emission factors from authoritative sources, updated annually. 38 of 82 factors are provisional — industry-typical values pending verification, including9 in Scope 1/2 categories (coal, heavy fuel oils, purchased steam, and process emissions) — and all provisional factors are flagged in generated reports.
EPA GHG Emission Factors Hub 2025
US EPA
Stationary combustion, mobile, fugitive, electricity
eGRID2023
US EPA
Subregion-level grid emission factors (lbs/MWh), location-based
IPCC AR5 GWP-100
IPCC
Global warming potentials for methane (CH₄) and refrigerants (F-gases)
Factor explorer
All 82 factors in the catalog the product applies, in kg CO₂e per unit.
| Activity | Factor | Source |
|---|---|---|
Natural Gas Scope 1 · Stationary Combustion | 53.06 / MMBtu 5.306 / therms 54.44 / MCF 50.29 / GJ | EPA GHG Emission Factors Hub 2025 |
Propane Scope 1 · Stationary Combustion | 62.87 / MMBtu 5.72 / gallons 1.5111 / liters | EPA GHG Emission Factors Hub 2025 |
Diesel Scope 1 · Stationary Combustion | 73.96 / MMBtu 10.21 / gallons 2.6972 / liters | EPA GHG Emission Factors Hub 2025 |
Fuel Oil No. 1 Scope 1 · Stationary Combustion | 73.25 / MMBtu 10.18 / gallons | EPA GHG Emission Factors Hub 2025 |
Fuel Oil No. 2 Scope 1 · Stationary Combustion | 73.96 / MMBtu 10.21 / gallons | EPA GHG Emission Factors Hub 2025 |
Fuel Oil No. 4 Scope 1 · Stationary Combustion | 10.69 / gallons | EPA GHG Emission Factors Hub 2025 Provisional |
Fuel Oil No. 6 Scope 1 · Stationary Combustion | 11.1 / gallons | EPA GHG Emission Factors Hub 2025 Provisional |
Kerosene Scope 1 · Stationary Combustion | 75.2 / MMBtu 10.15 / gallons | EPA GHG Emission Factors Hub 2025 |
Gasoline Scope 1 · Stationary Combustion | 8.78 / gallons | EPA GHG Emission Factors Hub 2025 |
Coal Scope 1 · Stationary Combustion | 95.35 / MMBtu 2,070 / short tons 2,280 / metric tons | EPA GHG Emission Factors Hub 2025 Provisional |
Lignite Coal Scope 1 · Stationary Combustion | 1,410 / short tons | EPA GHG Emission Factors Hub 2025 |
Wood and Wood Residuals Scope 1 · Stationary Combustion | 1,640 / short tons | EPA GHG Emission Factors Hub 2025 |
Methodology FAQ
Which emission factor databases does Eco-Auditor use?
Is Eco-Auditor aligned with the GHG Protocol?
How does Eco-Auditor handle data quality?
What compliance frameworks does Eco-Auditor support?
How often are emission factors updated?
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