DEFRA freight transport methodology

[/transport/defra/freight]

This page represents a greenhouse gas emissions methodology for the freighting of goods. The data and calculation methodology originates from the UK government department DEFRA, as published in their most recent Greenhouse Gas Conversion Factors for Company Reporting^[1] documentation.

The methodology

Emissions model

The emissions methodology is based upon emissions factors which describe the rate at which greenhouse gas emissions are produced during the freighting of goods in relation to distance travelled and the quantity of goods freighted. These emissions factors represent emissions associated with individual units of freight, which can be contrasted with similar transport-related emissions factors which describe emissions on the basis of entire vehicles (e.g. entire ship or lorry).

Emissions - expressed in terms of mass (e.g. kg) - are calculated by multiplying these rates (mass emitted per mass per distance; e.g. kg CO₂ per tonne km) by a distance (e.g km) and quantity (e.g. tonne) freighted.

Model data

The rate at which freight transportation produces greenhouse gas emissions varies with the mode of transport, depending on factors such as the fuel efficiency (i.e. the distance acheived per unit of fuel consumed) of the particular type of vehicle (e.g. lorry, plane, train, ship) as well as the typical freight loading. Fuel efficiency may be related factors such as the type of fuel used (e.g. petrol, diesel, biofuel, electricity) and the physical dynamics of the transportation context (i.e. road, rail, water, air). The loading of freight indicates the extent to which the emissions of the entire vehicle can be 'shared' between units of freight. Therefore, emissions factors for a broad range of generalised freight transport scenarios are provided.

A total of 75 specific types of freight transport scenarios are represented and are differentiated by transport type (i.e. ship, plane, rail, van, heavy goods vehicle), subtype (e.g. 'petrol' versus 'diesel' vans, 'crude tanker' versus 'general cargo' in shipping) and vehicle size (e.g. gross vehicle weight, deadweight tonnes, TEU, CEU).

Each freight transport type is represented by six distinct emissions factors which differentiate greenhouse gas emissions into the following types:

direct CO₂ emissions: carbon dioxide emissions produced during freighting, i.e. fuel combustion
direct CH₄ emissions: methane emissions produced during freighting, i.e. fuel combustion
direct N₂O emissions: nitrous oxide emissions produced during freighting, i.e. fuel combustion
total direct emissions: all direct emissions, i.e. CO₂ + CH₄ + N₂O
indirect emissions: emissions associated with stages in the fuel production chain such as raw material extraction and fuel delivery
total or 'life cycle': the total of direct and indirect emissions

Each of these emissions factors are expressed in terms of kg CO₂e per tonne km.

Activity data required

According to this methodology, greenhouse gas emissions are directly proportionate to distance and quantity (mass) of goods freighted, both of which therefore must be specified in order to make an emissions calculation.

Calculation and results

This emissions calculated by this methodology represent those per unit of freight and therefore should be considered attributable to the freighting of the specified quantity of freight only (rather than, say, the emissions attributable to the entire vehicle(s) on which it was transported).

The methodology calculates several emissions quantities including direct CO₂, CH₄, N₂O as well as indirect and total life cycle emissions. All quantities in this methodology are expressed in terms of CO₂e - the quantity of CO₂ which would exert the same atmospheric warming effect and the emissions quantity.

Additional information

Great circle distance 'uplift' factors

Following IPCC advice, the DEFRA methodology stipulates that flight distances which are defined as direct 'great circle' distances between two locations should be inflated by 9% in order to account for the typical indirect routing of actual flights and deviations related to congestion. The calculations for air travel made herein assume that the distance specifed is known to be the actual distance flown - rather than the distance estimated on the basis of the Great Circle - and therefore this adjustment factor is not applied. In order to make calculations based on Great Circle estimates between two locations (airports or specifed by latitiude/longitude) see the Great Circle route methodology.

Related methodologies

Other DEFRA transport methodologies available representing road vehicles differentiated by size and market segment, heavy goods vehicles and passenger transport are also available.

Useful links

DEFRA / DECC's Greenhouse Gas Conversion Factors for Company Reporting homepage

	UID	Label
	IL0VF690FB0G	heavy goods vehicle, all, uk average
	O78B8Y7BPMYS	heavy goods vehicle, articulated, 3.5-33 t
	3NCTR4YMZT93	heavy goods vehicle, articulated, above 33 t
	UD38UJAZE63Z	heavy goods vehicle, articulated, uk average
	TVAK6VS7A0JS	heavy goods vehicle, rigid, 3.5-7.5 t
	VVCCUPBOD22I	heavy goods vehicle, rigid, 7.5-17 t
	V79BPQIJWM90	heavy goods vehicle, rigid, above 17 t
	AE9HLGCZHQYB	heavy goods vehicle, rigid, uk average
	2XD89BTTKIR5	plane, domestic
	THLRNABYGWOH	plane, long-haul international
	3Y4EK4GUAGC2	plane, short-haul international
	A1CQC2KQBOAL	rail, diesel/electric
	3Q41I028HH4R	ship, bulk carrier, 0-9999 dwt
	5I3YJHY90E5W	ship, bulk carrier, 10 000-34 999 dwt
	08NBWIPRXQM5	ship, bulk carrier, 100 000-199 999 dwt
	VM84Y6WY0E6J	ship, bulk carrier, 35 000-59 999 dwt
	XPYIJL8C6V48	ship, bulk carrier, 60 000-99 999 dwt
	1PCW0EGTGVNY	ship, bulk carrier, average
	PABQ3SZLRZ0X	ship, bulk carrier, over 200 000 dwt
	T1E0JKKZVOEG	ship, chemical tanker, 0-4999 dwt

Name: DEFRA_freight_transport_methodology

Full path: /transport/defra/freight

Parent Category: DEFRA methodologies for transport

Provenance: DEFRA

calculation defra defra_annex7 direct distance emission_factor heavy_goods indirect lca light_goods mass plane road ship train transport UK