Supplier Carbon Questionnaire: Scope 1 and 2 From Your Fuel and Power Bills

Your buyer’s supplier carbon questionnaire asks for Scope 1, Scope 2 twice (location-based and market-based), energy by source and emissions per kilogram. A dyehouse can fill every one of those fields from four records it already keeps: the electricity bill, the coal stock ledger, the genset diesel log and the dispatch register. What a buyer or verifier checks is less the arithmetic than the emission factors behind it: which factor, from which publisher, for which year, on which basis.

This page takes one year of an illustrative knit dyehouse in India through those fields, following the GHG Protocol Corporate Standard, its Scope 2 Guidance, and the energy section of the Higg FEM (Facility Environmental Module). The dyehouse and every figure in its records are invented to show the method; they are not a real mill’s data. The emission factors are real, and each is linked to its publisher. Every calculation is run in this site’s calculators, and each link opens the tool with the example’s figures already entered.

What a supplier carbon questionnaire asks, and where each field comes from

Buyers’ spreadsheets differ in layout, but the fields come from two documented sources: the GHG Protocol, which defines Scope 1 and Scope 2, and the Higg FEM, whose energy section asks for the same data in its own form. The table lists each field with the rule behind it.

The GHG Protocol is revising the Scope 2 Guidance. A public consultation ran from 20 October 2025 to 31 January 2026, and its feedback summary of 29 July 2026 records that the Independent Standards Board asked in July 2026 for further work on the market-based method. No revised guidance had been published when this page was last verified, so the fields below follow the 2015 text.

The dyehouse’s year, from its own records

The illustrative dyehouse processes knitted cotton fabric on batch machines. Its reporting year is India’s financial year 2025-26, 1 April 2025 to 31 March 2026, with 300 operating days. It buys grid electricity, raises steam in a coal-fired boiler, runs a diesel genset during outages, and owns a 300 kWp rooftop solar plant whose output it uses on site and registers for no certificates. Its coal supplier certifies the coal as sub-bituminous, with a gross calorific value of 4,600 kcal/kg and a net calorific value of 4,370 kcal/kg (18.30 GJ per tonne), both as received. Its diesel delivery notes give a density of 0.835 kg per litre.

Three habits keep these columns defensible. Coal fired is opening stock plus receipts minus closing stock, not purchases. Grid kWh is the import register; if the plant exports solar under net metering, the net figure on the bill understates what it drew from the grid. And dispatched kilograms come from delivery challans, the record a verifier can trace. The genset’s own meter shows it made 80,400 kWh from the 24,000 litres.

Scope 1: the boiler and the genset

Coal

A fuel’s factor per tonne is its net calorific value times its carbon dioxide per unit of energy. The default for sub-bituminous coal in the IPCC 2006 Guidelines, Volume 2, Table 1.4 is 96,100 kg CO2 per terajoule (96.1 kg per GJ); for other bituminous coal it is 94,600. With this coal’s 18.30 GJ per tonne:

• Factor: 18.30 GJ/t × 96.1 kg CO2/GJ = 1.759 t CO2 per tonne of coal as received.
• Coal line: 2,520 t × 1.759 = 4,432.68 t CO2.

The carbon footprint calculator with the coal and grid figures entered takes the year as a daily average over 300 operating days: 5,700 kWh a day from the grid and 8.40 t of coal a day. Its fuel line shows 14.78 t CO2 a day, which over 300 days is the 4,432.68 t above. Its electricity line is the subject of the next section.

Replace the calculator’s default coal factor. The tool opens at 2.42 t CO2 per tonne, which its own explanation derives from bituminous coal at 25.6 GJ per tonne. On this dyehouse’s coal that default would report 6,098.40 t, 38% too high, because a tonne of this coal carries 18.30 GJ, not 25.6. Work the factor out from your own certificate every time the grade changes. If the certificate prints only the gross calorific value, IPCC notes that the net value is about 5% lower for coal and oil and about 10% lower for natural gas; better still, ask the laboratory for the net value. ISO 1928 measures the gross value and gives the formulae for calculating the net value from it.

Diesel

24,000 litres × 0.835 kg per litre = 20.04 t of diesel. IPCC’s defaults for gas/diesel oil are a net calorific value of 43.0 GJ per tonne (Table 1.2) and 74,100 kg CO2 per terajoule, so the factor is 43.0 × 74.1 / 1,000 = 3.186 t CO2 per tonne, or 2.66 kg per litre at this density. The genset line is 20.04 × 3.186 = 63.85 t CO2.

The calculator has one fuel field, so the genset needs a second run for the genset: grid set to zero, 0.0668 t of diesel a day at 3.186. Its annual line reads 63.85 t. The kilowatt-hours the genset made are not Scope 2: you generated them, and the diesel behind them is already counted here.

The Scope 1 total, and the other two gases

Coal plus diesel: 4,496.53 t CO2. The calculator counts carbon dioxide only. The GHG Protocol asks for each gas separately and in CO2 equivalent, using 100-year global warming potentials from one IPCC assessment report, named in the report (2013 amendment on required gases). With the IPCC default factors for manufacturing in Table 2.3 of the same volume (coal: 10 kg methane and 1.5 kg nitrous oxide per terajoule; diesel: 3 and 0.6) and the IPCC Sixth Assessment Report values (29.8 for fossil methane, 273 for nitrous oxide):

• Methane 0.46 t and nitrous oxide 0.07 t, adding 32.63 t CO2e for the coal and 0.22 t for the diesel.
• Scope 1: 4,529.37 t CO2e. The Higg FEM uses the same Sixth Assessment Report potentials and includes these gases in its own calculation.

If your boiler burns something else. For piped natural gas, the bill gives cubic metres; multiply by the supplier’s net calorific value per cubic metre to get GJ, then by IPCC’s 56.1 kg CO2 per GJ. For wood or other biomass, the Corporate Standard keeps the carbon dioxide out of Scope 1 and has you report it on a separate line; the methane and nitrous oxide from burning it stay in Scope 1. The FEM lists certified and uncertified biomass as separate sources and asks for the certificates.

Refrigerants. Leaks from chillers and air conditioners are Scope 1 fugitive emissions under the Corporate Standard, and the FEM collects them in its Air section. The top-up log is the record. The illustrative dyehouse logged none.

Scope 2: two figures from one bill

Location-based

India’s grid factor comes from the Central Electricity Authority’s CO2 Baseline Database for the Indian Power Sector. The latest edition is version 22.0 (user guide dated August 2026), covering financial year 2025-26. Its weighted average emission factor for the Indian grid is 0.675 t CO2 per MWh.

• Scope 2, location-based: 1,710 MWh × 0.675 = 1,154.25 t CO2.
• In the calculator link above, the electricity line shows 3.85 t a day, which over 300 days is the same 1,154.25 t.

Three things to get right with the CEA figure:

• Use the weighted average, not the margins. The database also publishes an operating margin (0.963), a build margin (0.446) and a combined margin (0.705). Those exist for carbon-credit project baselines. The location-based method asks for an average of all generation on the grid, which is the weighted average.
• It is carbon dioxide only, measured at the power station. Losses in transmission and distribution are not added to Scope 2; the Scope 2 Guidance (section 4.2) places them in Scope 3, category 3.
• Match the year. CEA publishes by Indian financial year. The previous edition, version 21.0, gave 0.710 for 2024-25. That is also the carbon footprint calculator’s default (0.71). For a 2025-26 year the default overstates Scope 2 by 5%, giving 1,214.10 t; for a 2024-25 year it is the right number. If your buyer wants the calendar year, say which edition you applied to which months.

Market-based

The Scope 2 Guidance names India among the markets where contractual instruments exist, and requires both figures, each labelled, wherever they do. The market-based figure draws, from the most precise source to the least, on energy attribute certificates or contracts that meet the Scope 2 Quality Criteria (Table 7.1), then a supplier-specific rate, then a residual mix, then the grid average.

The illustrative dyehouse holds no certificates or contracts. CEA publishes four factors and none of them is a residual mix, so its market-based figure falls back to the grid average: 1,154.25 t CO2, the same number as the location-based one. The guidance then requires a note that no residual mix was available and that the figure may double count with other consumers’ claims.

To lower the market-based figure, a certificate must carry the emission-rate claim for the electricity, be the only certificate claiming it, be tracked and retired by you or on your behalf, be issued as close as possible to the period you consumed, and come from the market where you consume. The FEM adds that certificates must be retired under the facility’s legal name and address, with the scheme’s retirement record uploaded. Where they come from:

• The I-TRACK Foundation’s issuer list names ICX, a subsidiary of the Indian Energy Exchange, as the I-REC(E) issuer in India, and the Green Certificate Company as the issuer for Bangladesh.
• India also runs its own renewable energy certificates under the CERC REC Regulations, 2022, with a registry operated by Grid-India as the Central Agency (REC Registry of India).
• Whether a particular instrument meets your buyer’s programme is your buyer’s call. Ask before you buy.

Had the dyehouse retired I-RECs for 500 MWh of its consumption, its market-based figure would be (1,710 − 500) MWh × 0.675 = 816.75 t CO2. The location-based figure stays at 1,154.25 t.

The rooftop solar

Electricity from a plant you own, with no certificates sold, carries no Scope 2 (Table 6.1 of the Scope 2 Guidance). The 372,000 kWh go in the energy fields as on-site solar, with the plant’s 300 kWp, which the FEM asks for. If you sold the plant’s certificates, those kilowatt-hours are accounted like grid electricity in both methods. If a developer owns the rooftop plant and sells you its power, the FEM classes it as “Purchased Renewables”, not on-site solar.

Bangladesh

Bangladesh’s Department of Environment, on behalf of the country’s Article 6 Designated National Authority, gave the grid emission factor in a letter of 23 January 2025: 0.61 t CO2 per MWh for 2019-20 and 0.62 for 2020-21 and 2021-22, with the method in the country’s first Biennial Update Report. The letter was issued for carbon-market purposes, and the Biennial Update Report it points to shows the figures are combined margins (operating margin 0.59, build margin 0.66), not an average of all generation. The GHG Protocol’s Scope 2 Guidance does not use margin factors for location-based Scope 2, so if you use this one, label it as a combined margin with its source and year, and tell your buyer what it is.

The FEM computes its own figure

The How to Higg guide states that from FEM 2024 the platform applies its standard country emission factor to purchased electricity and, for now, does not use a custom factor you enter. The Scope 2 the FEM displays may therefore differ from the figure you give your buyer. That is expected. It is why the factor, source and year belong beside every number you send.

Energy: one total, each source counted once

The genset’s 80,400 kWh are not added: its diesel is already in the total. Solar is 2.5% of all energy, and 17.2% of the 2,162,400 kWh of electricity the site used. State the calorific basis next to the total, because a gross-basis total for the same fuels would be higher.

The coal ledger is the Scope 1 source; the boiler log is its cross-check. The boiler efficiency calculator with the boiler log entered takes an hour’s steady running: 2,000 kg of steam an hour at 2,773 kJ/kg from feedwater at 356 kJ/kg, on 350 kg of coal at 18,300 kJ/kg. It shows a direct-method efficiency of 75.47% (on the net basis) and 5.71 kg of steam per kilogram of coal. Over the 7,200 boiler hours, that is 14,400 t of steam on the ledger’s 2,520 t of coal. If the log and the ledger disagree by more than the meters’ error, resolve that before you answer.

The energy per good kilogram calculator with the year entered turns the year into an ISO 50001-style indicator (ISO 50001). It values the 14,400 t of steam at 671.4 kWh per tonne and 75.47% efficiency to rebuild the coal, and takes 2,082,000 kWh of grid plus solar as electricity. The tool has no genset field, so the diesel’s 239,367 kWh go in its direct-fired fuel field, which is also fuel burned on site outside the boiler. Output is 2,760,000 kg processed, 82,800 kg of it not saleable. It shows:

• Site energy: 15,131,967.24 kWh, the table’s total within 0.01%.
• 5.65 kWh per good kilogram, against 5.48 per kilogram processed.
• 3,142,440.24 kWh lost in the boiler house, a fifth of the site’s energy.

Emissions per kilogram

Scope 1 plus location-based Scope 2 is 4,496.53 + 1,154.25 = 5,650.78 t CO2. Over 2,677,200 kg dispatched, that is 2.11 kg CO2 per kg. The two calculator runs show it in two parts: 2.09 for coal and grid, 0.02 for the genset. They take dispatched kilograms because the FEM’s production volume is the quantity shipped or sold. The calculator’s own notes suggest kilograms processed, which gives 2.05; both are legitimate, but they are different numbers, so name the denominator. On the market-based figure with 500 MWh of certificates, the intensity would be 1.98.

The answers, as you would enter them

If the buyer asks for an inventory to an international standard, ISO 14064-1 specifies how an organisation quantifies and reports its greenhouse gas emissions and removals.

What this questionnaire leaves out

Scope 1 and Scope 2 describe the site. The rest of a fabric’s footprint is Scope 3: the yarn or greige fabric, dyes and chemicals, freight, waste, and the upstream emissions of the fuel and power you bought, including grid losses. The Scope 3 footprint calculator opens with this dyehouse’s Scope 1 and Scope 2 carried in; replace its placeholder figures for materials, freight and waste with your own before reading its total.

How this page is kept

Last verified: 3 October 2026. This page is built from the GHG Protocol Corporate Standard and Scope 2 Guidance; the 2006 IPCC Guidelines, Volume 2; the IPCC Sixth Assessment Report’s global warming potentials; the CEA CO2 Baseline Database, versions 21.0 and 22.0; the Bangladesh Department of Environment’s grid emission factor letter; Cascale’s How to Higg guide for FEM 2025; and the I-TRACK Foundation’s issuer list. Each is linked where it is used. The dyehouse and its records are invented; the calculator links reproduce its figures. When CEA publishes a new edition, or the GHG Protocol publishes its revised Scope 2 guidance, the factors and rules here are updated. This page describes published accounting rules and emission factors; it is not verification or advice on a particular site’s inventory. Corrections are welcome through the contact page.