Efficiency of transport modes
Efficiency of transport modes
The emissions figures for each transport mode presented in the previous section are largely dependent on the usage of that transport mode, therefore they do not give any information on how efficient that mode of transport is for a passenger to travel on. This section presents a discussion of the efficiency of various transport modes, measured in terms of their emissions per passenger kilometre (pkm). The data presented in this section are provided by DEFRA[7] and are for the UK as a whole, not just Scotland.
The table below provides the average efficiencies of key transport modes for the years 2012-2018.
Sector | Mode and fuel | gCO2e/pkm | ||||||
---|---|---|---|---|---|---|---|---|
2012 | 2013 | 2014 | 2015 | 2016 | 2017 | 2018 | ||
Road | Average petrol car[8] | 133 | 131 | 128 | 128 | 129 | 124 | 123 |
Average diesel car[8] | 124 | 121 | 123 | 122 | 123 | 119 | 119 | |
Average hybrid car[8] | 89 | 87 | 89 | 86 | 89 | 79 | 84 | |
Average petrol motorbike | 119 | 119 | 120 | 120 | 120 | 117 | 115 | |
Average bus | 112 | 112 | 110 | 109 | 102 | 103 | 101 | |
Average coach | 29 | 29 | 29 | 29 | 29 | 28 | 28 | |
Rail | National rail | 58 | 49 | 47 | 45 | 49 | 47 | 44 |
Light rail and tram | 68 | 60 | 62 | 55 | 54 | 44 | 39 | |
Ferry | Average foot and car passengers | 116 | 116 | 116 | 116 | 116 | 116 | 113 |
Aviation | Average domestic flight | 182 | 173 | 155 | 158 | 147 | 141 | 158 |
Average short haul international | 104 | 102 | 88 | 90 | 89 | 95 | 86 | |
Average long haul international | 119 | 120 | 111 | 105 | 101 | 104 | 112 |
A summary of trends in efficiency for different transport modes is presented below.
Road transport
Coach fuel efficiencies have remained stable over the years and is the most carbon-efficient method of travel of the key transport modes presented here.
Diesel cars were more emitting than petrol cars in 2018, with the difference between petrol and diesel car emissions having reduced substantially over the years. Hybrid cars were more efficient, with emissions of 31.6% and 29.2% less than petrol and diesel cars, respectively.
Rail
Other than coach travel, rail was the most efficient means of transport in 2018. Both national rail and light rail and tram services saw reductions in average emissions per passenger kilometre between 2012 and 2018. A number of factors may have influenced this, including increased electrification of the rail network, improved fuel efficiency of trains, and increased capacity of train services.
Aviation
Despite a reduction in average emissions per passenger kilometre of 22% between 2012 and 2017, domestic aviation remained the least efficient means of travel in 2017. Since a large proportion of aviation emissions is due to take-off and landing, international aviation is on average more efficient than domestic aviation per passenger kilometre.
Passenger ferries
Ferry travel saw little change in efficiency between 2012 and 2018. Improvements in efficiency of aviation have meant that for some journeys it is now more efficient to travel by air than by ferry.