Table 2.

Practice carbon footprint (vehicle km, CO₂ conversion factors⁸ and CO₂ emissions)

Vehicle type or travel mode	Engine size, l	Annualised distance, km	Kg CO2 per km (conversion factor)a	Annual CO2 emissions, tonnes
Diesel car	Average diesel	7332	0.1918	1.41
	Large (>2)	37 185	0.2416	8.98
	Medium (1.4–2)	71 159	0.1792	12.75
	Small (<1.4)	6989	0.1433	1.00
Petrol car	Average petrol	14 588	0.2076	3.03
	Large (>2)	23 828	0.2981	7.10
	Medium (1.4–2)	39 703	0.2111	8.38
	Small (<1.4)	83 072	0.1701	14.13
Bus, passenger		38 526	0.1475	5.68
Train, passenger		6066	0.0501	0.30
Walk		62 327	b	b
Cycle		0.00	b	b
Total				62.76

^aArcGIS (http://www.esri.com/software/arcgis/index.html).

^bNo carbon emissions are associated with these travel modes.