In the transport sector, the idea of decarbonisation is both a familiar goal yet an enduringly challenging problem. Moving people and goods around the world generates around a quarter of annual global carbon emissions. This contribution is why transport was such a key issue at the COP26 summit in November 2021.
The agreement of governmental targets on CO2 emission reductions and the setting of deadlines for the phase out of fossil fuels, important though they are, are perhaps most valuable in the way they establish a new baseline for future decision making. Here in the UK the pledge for zero emission heavy goods vehicles, first made in the Department for Transport’s Decarbonisation Transport plan, was a sign of commitments taking solid form. Under the proposal, the UK will become the first country to phase out new internal combustion-powered HGVs weighing up to 26 tonnes by 2035. All new HGVs sold in the UK will need to be zero emission by 2040. This is significant when you consider that HGVs account for around 18 per cent of road transport emissions in the UK.
Fuels and power: where change begins
Legislation can reshape markets at the stroke of a pen, but achieving change in practice is always a mixture of economics, technology, and scalability. This is why players across the road transport sector have been considering low carbon fuels like hydrogen, batteries and catenary systems (overhead cable power). Given the long-distances goods are transported, hydrogen, with an energy to weight ratio of 10x lithium-ion batteries, looks the most promising. But it also introduces some significant challenges of its own.
Truly ‘green hydrogen’ production, where the hydrogen extraction process itself doesn’t emit further CO2, is currently a fraction of what it needs to be. In the UK, the government has a target to increase production of low carbon hydrogen but initially costs will be high and availability will be low.
The lack of supporting green infrastructure creates a classic when-to-invest, when-to-transition dilemma. Many companies are investing in industrial facilities, but the industry finds itself in a ‘catch-22’ situation waiting for a key player to make the first move. One way to increase demand would be to start with decarbonising the public sector fleet, which would also help create jobs in the UK in manufacturing hydrogen vehicles.
The other low carbon solutions – batteries and catenary – have promise, but are more uncertain. Battery technology will need to improve to sufficiently power HGVs over long distances. While catenary systems are extremely energy efficient, huge investment would be needed to make this feasible and vehicle manufacturers would need to coalesce around this solution en masse. Arup is participating in the initial stages of a catenary HGV trial – one discussed at COP – and it remains an option to consider for now.
Leading by public sector example
Having set the regulatory wheels in motion, the public sector can also stimulate transition by converting the fleets of vehicles they directly operate or influence.
Buses are a good place to start. Unlike transport of goods, their routes are relatively stable, depots are often well distributed and ridership patterns are already understood. Authorities up and down the UK are already converting their fleets, with support from the Government’s Zero Emission Bus. For a city like Sheffield or Liverpool, these fleets are typically 700-900 vehicles – and responsible for two to three per cent of transport carbon emissions. Operators can already select between battery and hydrogen buses on the open market. Many shorter, inner-city services could run on batteries, though developing the supporting charging infrastructure might be more of a challenge on the longer, faster suburban and rural routes.
In our experience working with local bus operators it’s clear that with some careful planning, consideration of technologies and operational schedules, the transition to low carbon bus fleets is not just achievable, but when viewed in whole life cost terms, also affordable.
Reshaping road use
Part of the solution for decarbonising road transport lies in managing and shifting demand – shifting from the private car to public transport, particularly in cities, as well encouraging those who can to adopt safe, active travel.
This could be more achievable than it looks. In reality, more than half of trips that are less than five miles are made by car or van and here lies huge scope for shift in modes. The wider sustainable development agenda is helping to drive such behavioural change, with its focus on everything from air quality and urban health to congestion, how people live, work and move around.
Arup is helping cities to incentivise and achieve this change. In Cardiff our experts are working with the council to help it double the amount of cycle trips made within the city by 2030, as part of its goal of making walking or cycling the most popular mode of transport across the Welsh capital. Similarly in Leeds, we’re helping work through the practicalities of an active city transformation and the steps required to realise this ambition.
Never underestimate a deadline
Decarbonising road transport remains hugely complex. But it’s also clear that post-COP26, the rules of the game have changed. The public appetite for and acceptance of lower carbon and more sustainable modes of travel is growing, with regulation effectively providing an end date for polluting technologies. For all players in the sector, from fleet operators to manufacturers, regional authorities to city leaders – successful transition will require vocal public backing for the trials currently in play, and the bravery to support (and invest in) better alternatives as they emerge.
Accelerating the journey to net zero transport
New business models, new technologies, new policies, new sources of power – the transport industry is changing rapidly. From hydrogen trains to walking plans for tropical cities, from timber stations to city-scale low emission zones, from electric bus fleet conversions to low-carbon airports – Arup is helping to drive decarbonised transport in all its forms.