How do I add carbon criteria to supplier selection and purchase decisions?

Question

Senseible · Accepted Answer

Start with the few categories where most of your purchased emissions sit. Ask suppliers in those categories for document-backed emissions data in every quote, give carbon a fixed weight in your scoring or an internal carbon price in total cost, and write data sharing and reduction expectations into contracts. Rank purchased goods by spend and by a rough emissions estimate. Steel, aluminium, cement, chemicals, plastics and freight usually dominate for manufacturers. Apply carbon criteria to those first; for low impact spend, leave procurement unchanged. The GHG Protocol Scope 3 guidance prefers supplier-specific data over averages, so data you collect here also improves your own Scope 3 inventory. Supplier Scope 1 and 2 emissions for the last year, with the invoices or bills behind them. For key materials, a product carbon footprint per tonne or per unit, with its boundary. Production route or recycled content where it drives emissions. Any reduction target or plan. ISO 20400:2017 gives guidance on building sustainability into procurement policy, criteria and contract management. Weighted scoring: give carbon a fixed share of the technical score and publish it in the tender. Total cost of ownership: add tonnes x an internal carbon price to each quoted price. Minimum requirement: for some items, refuse quotes with no emissions data at all. Annual sharing of emissions data in an agreed format. Notice if the production route or energy source changes. A reduction expectation, reviewed yearly, rather than a penalty on day one. Right to see the evidence behind the figures.