d instead.
The information derived from these factors can be combined with data on direct emissions, i.e. those relating to actual fuel use (e.g. litres of fuel used, or derived from mileage estimates).
Are these factors directly comparable to those in the other models?
No. These emission factors are for the supply chain emissions of GHG resulting from the production and transportation of broad categories of goods and services. They express Scope 2 and 3 emissions as defined by the GHG Protocol. Because they encompass all the supply chain impacts (i.e. indirect emissions), these emission factors are not directly comparable with those from other models, which generally only include emissions from the point of use.
Can I use these factors to calculate emissions from energy use etc.
There are factors for a number of activities that are also covered in other models, such as:-
- fuels refined from crude oil
- mains electricity
- various modes of transport
If you have more specific/detailed information for such activities (eg. kWh of electricity rather than just £ spend, etc.) you should make calculations of emissions using the emission factors in the other models, eg. for Electricity the UK Grid emissions factor for each kWh consumed, etc.
However, these factors may still be useful for a rough initial calculation of the relative importance of these activities in the first instance.
Which products are included in which categories?
The categories are based upon the Standard Industrial Classification (SIC): further information on the SIC 2007 is available here:
UK Standard Industrial Classification 2007 (UK SIC 2007) - ONS
Do the factors take into account emissions relating to imported goods?
The factors are for products supplied for consumption in the UK but do take account of the emissions relating to the production of products imported for intermediate consumption (i.e. those products that are used by UK industries in the process of supplying products for consumption in the UK.
Do the factors take into account emissions relating to the formation of capital assets used in making the products?
The estimates do not incorporate any allowance for emissions relating to the formation of capital assets, whether in the UK or overseas.
How were these factors calculated?
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. For the factors in this Annex an input-output model of the world economy was used with two distinct regions - the UK and the Rest of World.
By using the input-output model, the industrial emissions are then attributed to final products bought by consumers. The result is an estimate of the total upstream emissions associated with the supply of a particular product group.
The supply chain emission factors are expressed on a purchasers' price basis in real terms (i.e. the actual sales price in that year including taxes on products and distribution margins).
The 2022 factors are based on the latest UK Footprint data published by DEFRA in 2022. Please note that there is a 3 year time lag producing the data, ie. 2022 factors are actually based on the 2019 UK Government Footprint Data, etc.
It is common to have a time lag in emissions factors, eg. the BEIS UK Government Grid Electricity factor for 2022 is actually based on emissions data from 2020.
It may be advisable to take subsequent price changes into account when using the factors. It should also be noted that emissions in more recent years may have changed because of subsequent changes in the structure and emissions intensity of the supply chain since.