The UK prime minister Boris Johnson has described COP26, the climate summit taking place in Glasgow in November, as the “turning point for humanity.” He has exhorted world leaders to take responsibility for curbing global warming by making commitments in four key areas: coal, cars, cash and trees. The transport sector has a critical role to play, if this ambition to stave off future temperature rises is ultimately to be achieved.
Road vehicles account for nearly 75 per cent of the total emissions from the transport sector, so clearly a major focus on reducing emissions from road transport will be needed. However, emissions from shipping and aviation have risen in previous years; without action, these are projected to increase substantially between now and 2050, so measures for addressing these transport modes will also be important.
Reducing emissions from transport requires a shift away from fossil fuels to a much wider range of more sustainable sources of energy with a lower carbon impact. A 2020 report by Ricardo for the European commission, “Determining the Environmental Impacts of Conventional and Alternatively Fuelled Vehicles Through Lifecycle Assessment,” examined the full lifecycle impacts of the different types of road vehicles and fuels available now and in the coming decades. The key findings were that electric vehicles are already less damaging to the environment than vehicles powered by fossil fuels.
However, it is not enough to simply shift from one energy source to another. Fundamentally, a genuine modal shift is required that will most likely require each of us to ask the question: are our journeys really necessary?
The UK may have seen a 13 per cent reduction in the number of trips undertaken by car drivers since 2002, but congestion still costs the UK economy £6.9bn per year—in addition to the negative impacts on health and the environment. According to the ONS, at the height of the Covid-19 pandemic in April 2020, 46.6 per cent of people in employment within the UK did some work at home— of whom 86 per cent did so as a result of the pandemic. As restrictions have eased, some businesses have given employees greater flexibility about where they work. This has added a new dimension to the debate about the need for private car ownership for commuting, in contrast to more sustainable modes or mobility sharing.
When it comes to the movement of people and goods, it is clear that what is required is access to a range of vehicles suited to different purposes depending on the journey type. The last 18 months have seen an increase in light van traffic and new leasing solutions for last-mile delivery, including ultra-lightweight electric cargo vehicles and bikes, that are not based on upfront purchase and ownership. Similarly, C40, a charity and network of the world’s megacities committed to addressing climate change, has argued that cities with the most successful transport strategies are prioritising the movement of people, driving a modal shift from private vehicle use to a combination of public transport, walking and cycling. The mayor of London’s 2018 transport strategy set a target of 80 per cent of all trips in the city to be made by walking, cycling or public transport by 2041, up from 65 per cent today.
Around 98 per cent of the energy used to power the global transport sector derives from crude oil. This will not be replaced by a single sustainable energy source, but by a mix that includes electricity, hydrogen, sustainable biofuels and green ammonia.
Ricardo is involved in many projects exploring the potential of alternative energy sources for transport. First is the Project Fresson consortium, led by Cranfield Aerospace Solutions, which is exploiting recent advances in hydrogen fuel cell technology to develop a commercially viable, retrofit powertrain solution for the nine-passenger Britten-Norman Islander aircraft. Secondly is Riding Sunbeams, a project demonstrating that solar PV panels can be installed by railway lines and connected directly to electrified track to provide traction power for trains, bypassing the grid completely. Solar traction power could provide at least one-tenth of the energy needed to power trains on the UK’s direct current electrified routes every year.
In addition to greenhouse gas reductions, electrification of road transport brings significant air quality benefits, with reductions in levels of major pollutants including nitrogen dioxide (NO2)—implicated in asthma, chronically reduced lung function and other respiratory illnesses—and fine particulate matter (PM10 and PM2.5) which can worsen conditions such as asthma and heart disease, and even be a contributing factor of lung cancer.
Vehicle tailpipe emissions will greatly reduce with more widespread use of EVs. Some non-exhaust emissions, for example from braking, may also reduce due to the regenerative braking system deployed in EVs (though others, such as tyre wear emissions, remain an issue).
Reduced traffic levels as a result of restrictions on human and business activity during lockdowns across the world showed how air quality can improve. A report in the Lancet noted that lockdown interventions led to substantial reductions in PM2.5 concentrations in China and Europe, with tens of thousands of premature deaths from air pollution avoided. The report also stated that such improvements in air quality are achievable in future, if stringent emission control policies are adopted—a challenge for governments, authorities and agencies to embed cleaner, safer transport behaviours in the long term.
Another factor to bear in mind is that CO2 emissions from UK electricity generation fell by 48 per cent in the five years between 2016 and 2021, in part due to coal being replaced by gas and renewables. An electric car purchased five years ago will now generate lower total emissions due to ongoing decarbonisation of the electricity generation sector. Further reductions in these emissions are likely to continue as more renewable electricity becomes available—something impossible with petrol or diesel vehicles.
In the current era of rapid technological development and transition, multiple solutions will co-exist. For new light-duty vehicles, it is clear that internal combustion engines have a limited lifetime remaining, as numerous governments around the world introduce proposals to phase out this technology. For heavier transport modes where internal combustion engines will remain in use for some time to come, they will increasingly integrate electrified technologies and even full electric propulsion systems. Furthermore, transport fuels will integrate novel energy resources, such as advanced biofuels and new synthetic pathways. At Ricardo, we are experts in using lifecycle assessment (LCA) techniques to compare the overall environmental burdens of each solution, taking into account the production, use and disposal phases of vehicles and fuels.
Crucially, moving from measuring tailpipe emissions to an approach based on assessing the full lifecycle environmental burdens of options for the transport sector makes it clear: there are solutions in addition to electrification that can contribute to the decarbonisation of transport. As an environmental, engineering and strategic consulting company supporting the decarbonisation of the global transport and energy sectors, Ricardo is well placed to advance this holistic approach.
