Frequently asked questions

A GHG inventory is a company's organised record of its greenhouse gas emissions for one period, usually a financial year, split into Scope 1, 2 and 3 and expressed in tonnes of CO2 equivalent. It lists the sources, data, emission factors and assumptions used.

Multiply each activity, such as litres of fuel or kWh of electricity, by a sourced emission factor, convert other gases with GWPs, and add the results by scope. Start with 12 months of fuel and electricity records, CEA grid factors and IPCC fuel defaults.

For the location-based figure, use the grid emission factor in the Central Electricity Authority's CO2 Baseline Database, choosing the version and financial year that match your reporting year. Do not use UK or other foreign grid factors for Indian electricity.

Both set rules for organisation-level inventories and are broadly compatible. The GHG Protocol groups emissions into three scopes, while ISO 14064-1:2018 uses direct emissions plus several indirect categories. In July 2026 the two bodies announced plans to merge their corporate standards by Q4 2028.

Not by law for most unlisted MSMEs as of October 2026, though a buyer or lender may ask for it. Mandatory assessment or assurance applies to BRSR Core for top listed companies. A clear method note and audit trail make later verification under ISO 14064-3 much easier.

A base year is the reference year you compare future emissions against. The GHG Protocol requires a recalculation policy, so that if you buy or sell a plant or fix a major error, the base year is adjusted and your trend stays fair.

You can use the UK government conversion factors, now published by DESNZ, for items with no Indian factor, such as some travel or materials, if you disclose it. Never use their UK electricity factor for Indian power; use CEA instead.

No. A spreadsheet is enough for most MSMEs with a few sites, and GHG Protocol and the India GHG Program offer free calculation tools. Software helps when you have many sites or suppliers, but check which factor sources and versions it uses.