Indirect Emissions Supply Chain

Emission Factor Origin

This category is intended for use as a high-level diagnostic tool and is not a replacement for more specific information if available.

The emission factors here are based on the amount spent (in pounds sterling excluding VAT) on each group of products and include the raw material extraction, processing, manufacturing, transportation and packaging. These factors are derived from a multi-region model, so take some account of emissions relating to imported goods. The results derived here can be combined with direct emission calculations (e.g. those relating to actual fuel use) to provide full life-cycle emissions.

The factors are based on a model of the economy, known as the input-output model, which describes in monetary terms how the goods and services produced by different sectors of the economy are used by other sectors to produce their own output. These monetary accounts are linked to information about the greenhouse gas emissions of different sectors of the economy. By using the input-output model, these emissions are then attributed to the monetary transactions taking place in the economy. The result is an estimate of the total upstream emissions associated with the supply of a particular product group. The input-output tables used here are in 2006 basic prices; therefore, it will be advisable to take subsequent price changes into account when using this category. Changes in the supply chain since this time should also be taken into account.

How to use this category

Selecting an emissions scenario

Use the drill-down productCategory to chose the product type you wish to calculate emissions for.

Specifying activity data

The amountSpent, in pounds sterling, must then be set as a profile item value.

Results and calculation

The quantities returned represent the greenhouse gas emissions associated with the quantities and refrigerant type specified. The following quantities are returned:

• CO2: quantity of CO₂ emissions
• ch4CO2e: quantity of CH₄ emissions expressed in terms of CO₂e
• n2oCO2e: quantity of N₂O emissions expressed in terms of CO₂e
• hfcCO2e: quantity of HFC emissions expressed in terms of CO₂e
• pfcCO2e: quantity of PFC emissions expressed in terms of CO₂e
• sf6CO2e: quantity of SF₆ emissions expressed in terms of CO₂e
• totalCO2e: total, combined CO₂e emissions

Notes

CO₂e quantities

Emissions in this methodology are pre-converted into CO₂e. These conversions are not made by Discover.