Emissions from train travel

The calculator uses a figure of 100 g CO2 / mile.

This is based on an overall figure of 49 g/km i.e. 80 g / mile (or 0.080 kg / mile) - from the AEA Report [1]. This gives a range from 19 g/km to 71 g/km for intercity trains depending on route, engine type (diesel or electric) and passenger load (ranging from 44% to 68%).

Allowance is needed for the fossil fuel used in oil exploration and refining (which is overall around 85% efficient - see car sources page), and for train and track manufacture and maintenance. So the figure of 80 g / mile is adjusted to 100 g / mile.

Other estimates

g / kmg / mileSourceNotes
4980[1]The most detailed source, and the one used as a basis
4980[2]Recommended by CG, summarising several sources
60100[5]giving DEFRA as the original source
80130[7](underground / metro)
original source; after conversion

The factor used by the Carbon Independent calculator is thus in the middle of the range of published estimates.


[1]AEA Technology (2005) Environmental Costs of Rail Transport http://www.rail-reg.gov.uk/upload/pdf/aea_enviro_rep.pdf
[2]Chris Goodall (2007) (Earthscan)
[3]National Energy Foundation http://www.nef.org.uk/greencompany/co2calculator.htm (viewed 26.1.08)
[4]http://www.carbonfootprint.com/results.php (viewed 13.8.06)
[5]Carbon Emission Assumptions (Sep 2007) UK Department for Transport journey planner http://www.transportdirect.info/Web/Downloads/TransportDirectCO2Data.pdf
[6]Mark Lynas (2007) Carbon Counter (Collins)
[7]Hillman M, (2006) Personal carbon allowances British Medical Journal 332 1387-1388

First published: 2007
Last updated: 14 Nov 2022