# Should our plants send fuel and power quantities to head office, or calculate the CO2 themselves?

Canonical: https://senseible.earth/answers/plants-send-fuel-quantities-or-co2-to-head-office

Either works and the results should match. The GHG Protocol's centralised way has plants send fuel and power quantities for head office to convert. The decentralised way has plants calculate CO2 themselves. Choose the decentralised way when process emissions are large or methods differ by plant. Many companies mix both.

## Centralised: plants send quantities

Plants report activity data, such as litres of diesel or kWh, and the head office multiplies by emission factors. It suits office-based organisations, or cases where the calculation is standard across plants and head office can do it simply.

## Decentralised: plants send CO2

Plants calculate emissions using approved methods and report them. It raises awareness at the plant but needs training, adds calculation errors and means more auditing.

- Detailed knowledge of the equipment is needed for the calculation.
- Calculation methods differ between plants.
- Process emissions, not just fuel burning, are a big share.
- Training and audit resources exist, or a simple tool is available, or local rules require plant-level reporting.

## The mixed way

Complex plants with process emissions calculate their own emissions. Plants with standard sources report only fuel use, electricity and travel, and the head office tool does the sums.

## Checks that apply to both

- Plants collect the activity data either way.
- Head office can compare the two methods as a consistency check.
- Remove any Scope 2 or 3 emissions that another plant in the group already counts as Scope 1.
- Plants should also send a description of sources, exclusions with reasons, last year's figures, the reporting period and any uncertainties.

## What Senseible does here

Senseible turns your bills and invoices into verified emission records by site, so you can answer a buyer with figures you can trace to a document. Verified here means rule checks passed against the evidence. It is not third-party assurance.

- [Multi-plant MSME: one report or one per plant](https://senseible.earth/answers/multi-plant-msme-one-report-or-per-plant)
- [Combine plants into one BRSR figure](https://senseible.earth/answers/combine-plants-into-one-brsr-figure)
- [MSME carbon number](https://senseible.earth/msme-carbon-number)

Sources: [GHG Protocol, Corporate Accounting and Reporting Standard (revised edition)](https://ghgprotocol.org/sites/default/files/standards/ghg-protocol-revised.pdf)

Last reviewed 2026-11-04.