How are a refinery's emissions split between diesel, naphtha, polymers and other products?

There is no single answer. Standards prefer splitting by process unit first, then allocating what is left by a physical measure such as mass or energy content, and only then by price. The method changes each product's figure a lot, so a supplier's number is only comparable if you know which rule it used.

The order the standards set

1. Avoid allocation where you can: assign each process unit's fuel and process emissions to the streams it actually makes.
2. Where units make several products, split by a physical relationship such as mass or energy content.
3. Use economic value only when no physical relationship fits, and say so.

Why it matters to a buyer

A lubricant base oil or a polymer grade can carry very different figures under mass, energy or value allocation. Two refineries quoting different numbers may simply be using different rules, not running cleaner plants.

What to ask the supplier

• The allocation method and the boundary (gate of refinery or of the product plant).
• The year and whether captive power and steam are inside.
• Whether crude production and shipping are included upstream.

What Senseible does here

Senseible reads the invoices for the products you buy into a dated, fingerprinted record, so a supplier figure and the quantity it applies to can be traced back to the documents behind it. It does not calculate refinery allocations.

• Polymer resin factors
• Fuel gas factor
• Process flare CO2

Sources: ISO 14067:2018, Carbon footprint of products (iso.org), GHG Protocol Product Standard, GHG Protocol Corporate Value Chain (Scope 3) Standard

Last reviewed 2026-10-21.