The holy trinity of walking, cycling and public transport usually springs to mind when the term ‘sustainable transport’ is mentioned, whilst private vehicles sits at the polar opposite. Transport Canada identifies the goal of sustainable transport as “[ensuring] that environment, social and economic considerations are factored into decisions affecting transportation activity” (VTPI, 2017). However, with transport accounting for approximately 33% of all carbon dioxide emissions in the UK last year (BEIS, 2019), it forms the assumption that the UK tends to neglect the environmental component in what classes transport as “sustainable”, and it cannot be underestimated how important prioritising more environmentally sustainable modes of travel is moving forward.
The largest contributor towards the 33% of transport emissions in the country is passenger cars, making up 54% of transport related emissions (Element Energy, 2015), and with only 0.2 million out of the 39.4 million registered cars in the UK last year being ultra-low emissions vehicles (ONS, 2019), cars are clearly the least favourable day-to-day mode of transport in achieving the goals for sustainable transport. So what are the other options? And how can we do better?
In a lecture on sustainable transport systems, Alan Wann presents some ‘good examples’ of sustainable transport systems around the world, all of which have efficient and highly frequented public transport systems, which include metro, trams and buses. In England, 4.36 billion journeys were made last year (Department for Transport, 2019) across 32,000 buses (Stagecoach, n.d.). However, in the rise of the condemning of the use of cars and private vehicles due to their contribution to greenhouse gas emissions, is it really sustainable to promote another mode of transport that does exactly that? Just because there are more people that can be transported by a bus than a car, is that enough to work towards sustainability, especially in the climate crisis we face today? Whilst it is easy to criticise car users for being responsible for the majority of carbon dioxide emissions every year, and applaud those who leave their cars at home to take the bus instead as they are thought to be more ‘environmentally aware’, let’s look at the facts.
Between 2004 and 2010, carbon dioxide emissions from cars reduced from 75.3 million tonnes to 67.4 million tonnes, whilst those from buses actually increased from 4.5 million tonnes to 4.7 million tonnes (Future Travel, n.d.). Moreover, buses are thought to be much more sustainable than cars, but at 186 grams of carbon dioxide emissions per passenger kilometre, this only equates to 19 grams per passenger kilometre less than car emissions, at 205 grams of carbon dioxide per passenger kilometre (Future Travel, n.d.). When we calculate this per double decker bus which typically holds around 87 passengers (TfL,2014) that emits 16,182 grams of carbon dioxide per passenger kilometre at full capacity, compared to a 5 seater car at full capacity which emits 1,025 grams of carbon dioxide per passenger kilometre. Whilst this seems to work because of the vast difference between passenger quantity, what happens when it is late at night and that same bus is running with only 5 passengers on it? (Rowlatt, 2009) That roughly equates to 3,236 grams of carbon dioxide emissions per passenger kilometre, which is far more than the emissions from a car (Carbon Independent, 2019).
This of course does not take into account the marginal difference that extra weight makes on fuel consumption (Rowlatt, 2009) and therefore on carbon dioxide emissions, but the point I am making is – buses are a great option for sustainable transport when they are running at full capacity, particularly as most people that travel by bus will combine walking (to and from the bus stop) into their journey. However, with buses often running nearly empty – some in central London running at less than 70% full at peak times (Edwards, 2018) – does it really make sense to be running these buses every 3-4 minutes? (London Bus Routes, 2018)
Perhaps the problem here is not the use of buses, but instead the frequency of buses that we are using. At what point does convenience override efficiency and environmental sustainability? Personally, I am guilty of taking the bus into university because it is more convenient, and if I miss the bus on the way to the bus stop I know the next one is only 10 minutes away. But if the next one wasn’t for another half an hour or even hour, I would definitely walk instead. For those that don’t have the option of walking, a less frequent bus service should result in buses operating at a higher capacity, therefore ironically, reducing the number of buses could actually improve sustainability. But maybe we should all just invest in bicycles or better walking shoes instead…
Carbon Independent (2019) Emissions from Bus Travel, Available at https://www.carbonindependent.org/20.html. [Accessed on 18/12/19].
Department for Business, Energy and Industrial Strategy (2019) 2018 UK Greenhouse Gas Emissions, Provisional Figures, London.
Department for Transport (2019) Annual Bus Statistics: England 2017/18.
Edwards, T. (2018) Leaked documents reveal biggest bus shake-up for decades, BBC News.
Element Energy (2015) Quantifying the impact of real-world driving on total CO2 emissions from UK cars and vans, Cambridge.
Future Travel (n.d.) Statistics: Environment, Available at http://futuretravel.org.uk/statistics/. [Accessed on 17/12/19].
London Bus Routes (2018) Routes 38/N38, Available at http://www.londonbusroutes.net/times/038N038.htm. [Accessed on 19/12/19].
Office for National Statistics (2019) Road Transport and Air Emissions, Available at https://www.ons.gov.uk/economy/environmentalaccounts/articles/roadtransportandairemissions/2019-09-16. [Accessed on 17/12/19].
Rowlatt, J. (2009) Why cars are greener than buses (maybe), BBC News.
Stagecoach (n.d.) UK Bus Industry – FAQs, Available at: https://www.stagecoach.com/~/media/Files/S/Stagecoach-Group/Attachments/pdf/bus-industry-faqs-v2.pdf. [Accessed on 18/12/19].
Transport for London (2014) Route 66 switches to double decker, Available at https://tfl.gov.uk/info-for/media/press-releases/2014/august/route-66-switches-to-double-decker. [Accessed on 17/12/19].
Victoria Transport Policy Institute (2017) Sustainable Transportation and TDM, Available at https://www.vtpi.org/tdm/tdm67.htm. [Accessed on 16/12/19].