Gains:
- Ability to place an activity in the correct scope (1/2/3) and calculate it in tCO₂e with the logic of 'activity data × emission factor'
- Ability to confirm emission factor from official source and convert to CO₂e with correct GWP set for methane/N₂O and specify Scope 2 method
- Ability to produce verifiable results by having multi-line inventory totals made by artificial intelligence with executable code rather than manually
The most talked about number in the sustainability world is a company's carbon footprint: the total of greenhouse gases an organization releases into the atmosphere as a result of its activities. The name of the international framework that sets the rules for calculating this number is the GHG Protocol (Greenhouse Gas Protocol). Carbon accounting, like financial accounting, is based on certain definitions and limits; The slightest scope or unit error invalidates an entire report. In this unit, you will learn the rules of using artificial intelligence (AI) safely in carbon accounting.
Let's first define the common unit. The heating effect of different greenhouse gases (carbon dioxide CO₂, methane CH₄, nitrous oxide N₂O) is different. To convert it all into one common measure, CO₂e (carbon dioxide equivalent) is used. The coefficient of translation is GWP (Global Warming Potential): it tells you how strongly a gas warms compared to CO₂. For example, the 100-year GWP of methane is approximately 28; i.e. 1 tonne of methane ≈ 28 tonnes CO₂e. If GWP is omitted, methane and N₂O are greatly underestimated.
Three scopes: where the emissions come from
The GHG Protocol separates emissions into three scopes:
- Scope 1 (direct): Emissions from the company's own sources. Example: natural gas burned in the company boiler, fuel burned by company vehicles, generator diesel.
- Scope 2 (purchased energy): Indirect emissions from the production of purchased electricity, steam, heating and cooling. Electricity does not come out of the company's chimney, but the power plant that produces it emits emissions.
- Scope 3 (value chain): All other indirect emissions: purchased goods and services, business travel, employee transportation, use of product sold, waste. It is generally the largest but most difficult to measure part of the total footprint.
Activity
Scope
Burning natural gas in the company boiler
Scope 1
Gasoline for company vehicle
Scope 1
Electricity from the grid
Scope 2
purchased steam
Scope 2
Raw material purchased from supplier
Scope 3
Employee coming to work by car
Scope 3
Customer use of the product sold
Scope 3
Tip: There are two methods for Scope 2: location-based (uses the average grid factor for the area) and market-based (reflects the green energy contracts the company has purchased). The two yield different results, and most frameworks require both to be reported. Be sure to specify which one you use.
Basic logic of the calculation: activity data × emission factor
The heart of carbon accounting is a single multiplication:
Emission (CO₂e) = Activity data × Emission factor
Activity data is the measured quantity (litre of diesel, kWh of electricity, m³ of natural gas). The emission factor is the emission coefficient per unit (e.g. kgCO₂e/litre). This is where AI is most dangerous: emission factors vary by country, year and fuel, and AI can make up a factor it doesn't remember. The rule is clear: the factor is always confirmed from an official source (IPCC, DEFRA/EPA, IEA, national inventory); Only the calculation framework and code are made by AI.
Weak prompt / Strong prompt
Weak prompt:
Calculate our company's carbon footprint.
No scope, year, country, unit and factor source; AI makes up factors, confuses scopes, overlooks units.
Powerful prompt:
Your role: carbon accounting expert (GHG Protocol).Input (2024, Turkey):- Natural gas: 12,000 m³ (Scope 1)- Company vehicle diesel: 8,000 liters (Scope 1)- Mains electricity: 250,000 kWh (Scope 2, location-based)Task:1) Place each item in the correct scope.2) Calculate "activity data × emissions FIT factor = tCO₂e”, but DO NOT FIT emission factors — leave blank for factor and write “to be confirmed from official source (IPCC/DEFRA/national)”.3) Give the total not by hand, but with a formula I can run.4) Remind me of the location vs market distinction for Scope 2.Output: table (Item | Scope | Activity data | Unit | Factor[NULL] | Formula).
This approach uses AI as a computational scaffolding assistant; The factor leaves the decision up to you.
Put the total into code
Collecting dozens of items in a multi-line inventory is prone to error. After verifying the factors from the official source, have the AI do the sum with a code:
Write a calculation code/formula for the verified factor table below.Each row: activity_data × factor = kgCO2eNext: add up all kgCO2e and divide by 1000 to give tCO2e.I entered the factors and verified them; you just set up the calculation.Columns: A=item, B=activity_data, C=factor(kgCO2e/unit)Output: cell formulas + total formula, annotated.
The following prompt tests a completed inventory with an audit eye.
Your role: carbon inventory control specialist. Audit the following emissions inventory and flag (not correction):1) Items placed in the wrong scope (1/2/3).2) Emission factors with unspecified source.3) Gases with GWP conversion omitted (non-CO₂).4) Unit discrepancies (kg/tonne, m³/kWh).5) Whether the location/market method is specified for Scope 2. List each finding with justification; no factors or numbers FITTING.Inventory: [INVENTORY]
Caution: GWP sets are updated (e.g. IPCC AR5 and AR6 give different values). Indicate in the report which set of GWPs and which time horizon (usually 100 years) you used; Otherwise, data from two years become incomparable.
three mini cases
Case 1 — Contrived factor. A logistics company had YZ calculate 50,000 liters of diesel. YZ used 2.40 kgCO₂e/litre; the official factor was ~2.68. The difference meant an underestimation of approximately 14 tonnes of CO₂e. The factor was validated and corrected from the DEFRA dataset.
Case 2 — Scope confusion. An office company mistakenly placed the electricity it purchased in Scope 1. The pre-audit check revealed that the electricity was Scope 2 (purchased energy); If the coverages had not been corrected, both the total and category distribution would have been reported incorrectly.
Case 3 — GWP bypass. A waste facility directly collected methane emissions in tonnes, without converting them into CO₂e. When GWP=28 was applied, it was seen that 200 tons of methane actually emitted ~5,600 tons of CO₂e. If GWP was omitted, the footprint would be approximately 28 times smaller.
Common mistakes
- "Reminding" the AI of the emission factor. The factor is always taken from the official table by country and year; The factor given by the AI may be fake.
- Mixing scopes. Putting purchased electricity in Scope 1 and own fuel in Scope 2 distorts the total and distribution.
- Bypassing GWP. If methane and N₂O are not converted to CO₂e by GWP, the footprint is greatly incomplete.
- Mixing unit. Confusing kg with ton, m³ with kWh causes 1000 times error.
- Not specifying the Scope 2 method. If it is not stated whether it is location-based or market-based, the number cannot be compared.
In summary
Carbon accounting is not an art of guessing, but an accounting discipline based on definitions and verified factors. Emission = activity data × emission factor; but the factor is always confirmed from the official source, only scope separation, account scaffolding and total code are made to AI. Separate the three scopes correctly, convert all gases by GWP to CO₂e, fix the units and state your Scope 2 method. Do not include any factor given by AI in the report without verifying it.
Application task
Set yourself up with a small data set of three items (one Scope 1, one Scope 2, one Scope 3 item). Ask the AI with the powerful prompt above for an accounting scaffold that places each item in the correct scope and leaves the factor cells blank. Then: (1) find and enter each factor from an official source, (2) have the total calculated by code, (3) make a note of the GWP set and Scope 2 method you used.
checklist
- [ ] I placed each pen in the correct coverage (1/2/3).
- [ ] I have verified the emission factors from official source (IPCC/DEFRA/EPA/national).
- [ ] I converted all greenhouse gases to CO₂e with GWP.
- [ ] I did the sum not by hand but by executable formula/code.
- [ ] I checked the consistency of the units (kg/ton, m³/kWh).
- [ ] I specified the location/market method for Scope 2.
- [ ] I wrote the GWP set and time horizon I used in the report.