Installing overhead charging cables to power fleets of electric lorries would almost entirely eliminate UK road freight transport emissions by the late 2030s, according to a new government-funded report published this month.
The Centre for Sustainable Road Freight’s white paper on ‘e-highways’ said they would cost an estimated £19.3billion to implement the overhead lines, similar to those used on the rail network, but the savings from the technology would pay back the investment within 15 years.
It’s the latest measure being considered by government to reduce motorway pollution as part of a wider Clean Air plan.
Other proposals, which include changes to the 70mph speed limit, emission-capturing tunnels and barriers, and huge electric-car charging forecourts, would – if given the green light – drastically change the look of the country’s fastest-moving roads.
Could e-highways be coming to the UK? Overhead lines on motorways could help all but eliminate road freight pollution, a new report claims
The overhead lines are similar to those used on the rail network and lorries would be able to connect to them using rigs attached to the roof of the cab
1. E-highways: What are they and how would they work?
The SRF has looked into the eco benefits of introducing catenary cables in lane one of 4,300 miles of the UK’s busiest motorways for freight.
The charging lines link to lorries fitted with extendable rigs known as a pantographs, which would be mounted to the cabs of electric trucks.
The energy from the cables would be able to power the lorry’s electric motor en route but also recharge an onboard battery so the vehicle could reach their final destinations away from an e-highway while still using electric power.
The report says the Government could tax the electricity used by electrified lorries, enabling it to recover not just the costs of the installation but also the revenues lost from taxation of diesel fuel.
The overhead catenary system is described in the paper as a ‘safe technology’ that’s commonplace in the railway sector.
They can be built into motorways using overhead structures that holds two catenary cable systems.
These wires supply the positive and negative electrical circuit that is picked up through a pantograph collector on the roof of the HGV.
A lorry would be free to leave the wires to overtake or complete its journey away from the catenary using a separate on-board battery, which would be approximately the size of an electric car battery, also providing zero tailpipe emissions at all times.
Rigs on top of electric or hybrid HGVs would be able to link to the charging cables to not only power the electric motors in the lorries but also charge their batteries so they can continue on journeys away from e-highways while still using electric power
The overhead catenary system is described in the paper as a ‘safe technology’ that’s commonplace in the railway sector
The SRF report claims that the initial phase of installing e-highway technology on the busiest freight roads would take two years, cost £5.6billion and electrify the major routes that account for almost a third of all HGV use in the UK.
Two more phases will follow to expand an electrified network for the next generation of low-emission freight lorries.
The overhead lines would be powered by the national electricity grid, which is likely to set alarm bells ringing as concerns continue to mount about an increase in demand and eventual strain that will be caused when more drivers switch to electric vehicles that will commonly be charging overnight.
That said, the UK National Grid has also this week released a report looking into making its future sustainable, highlighting intentions for it to be carbon emissions negative by 2033 as it switches to renewable energy supplies.
E-highways are already being developed and tested at makeshift sites in Germany, Sweden and the US by tech firm Siemens and HGV-maker Scania.
This image shows a track with electric overhead contact wire for hybrid trucks on e-Highway in Luebeck, Germany
The Guardian reports that officials from the UK’s Department for Transport were scheduled to visit a test sites in Germany in March, but the trip was suspended due to the restrictions of the coronavirus pandemic.
Academics at SRF said a near-£20billion investment in the technology in the UK would put all but the remotest parts of the country within reach of electric trucks by the late 2030s.
The centre is backed by government research grants and industry partners, including major freight businesses such as John Lewis, Sainsbury’s and Tesco.
While the thought over overhead lines above a motorway might sound like an extreme measure, the government is coming under increasing pressure to find ways of reducing pollution levels on major roads.
Officials from the UK’s Department for Transport were scheduled to visit the test sites in Germany in March, but the trip was suspended due to the restrictions of the coronavirus pandemic
The road freight sector is widely known to be a significant contributor to the climate crisis, accounting for five per cent of the UK’s carbon dioxide emissions in 2018, according to government figures.
Last week, This is Money reported on Highways England’s failure to spend a £75million fund aimed at reducing motorway-related emissions over the last five years.
Other significant changes to motorways we might see
Motorists are already having to get their heads around the concept of ‘smart motorways’, which includes overhead gantries that provide speed-limit and lane-closure information, and four-lane routes without a hard shoulder.
But, along with e-highways, there are plenty of other suggestions being put forward for the adaptations of major trunk roads to curb harmful-emissions levels.
This is Money has outlined four additional measures being mulled to reduce air pollution and promote electric-car ownership that could entirely change the landscape of the motorways we know…
The Government has already toyed with the concept of installing emission tunnels on UK motorways to stop harmful pollutants spreading to nearby communities
2. Use of ‘pollution tunnels’ to contain emissions
Highways England in 2017 confirmed it was considering covering stretches of motorway in ’emission tunnels’ to protect locals from dangerous levels of pollution.
The agency said in an air quality strategy that it is exploring the possibility of building physical canopies around main roads to soak up car fumes.
In its report, Highways England says it is ‘investigating if we can reduce the costs to construct a canopy, which is a tunnel-like structure designed to prevent vehicle emissions reaching our neighbours’.
A scheme in the Netherlands was seen as the litmus test, which uses cantilevered canopies built over the most polluted sections of motorways to trap damaging pollutants such as nitrogen oxides (NOx), which have been closely linked to causing thousands of premature deaths each year.
Highways England is already trialling the use of air quality barriers that also shield nearby towns and cities from the harmful pollutants emitted by cars, vans and HGVs
3. More emissions barriers to block pollutants escaping into nearby towns
Highways England is already trialling ‘air quality barriers’ around the country, with the first erected on the M62 near Simister, Greater Manchester in 2015, costing £2.5million.
These were four-metre-high structures running along either side of a 100-metre long stretch of the road, which were later increased to a height of six metres in 2016.
Further trials, which use a barrier coated in a mineral polymer material to absorb nitrogen dioxide, have also been put in place at various locations.
According to Highways England, the barriers, which have been tested in other European countries work by ‘dispersing emissions and can act as an effective safeguard to communities near busy roads’.
A review of NOx emissions levels at motorways in England could see some having speed limits reduced from next year, though the Transport Secretary is also believed to be considering an increase to the national speed limit on motorways for the future when most will be driving EVs
4. Lower speed limits to cut NOx outputs from petrol and diesel vehicles – then increase it to reduce journey times when electric cars are mainstream
Highways England, the Department for Transport and the Joint Air Quality Unit have reviewed 101 sections of the strategic road network and assessed their compliance with legal limits for NOx.
However, the result of this review will not be published until next year, when the company will name which motorways requiring mitigation – and this could mean lowered speed limits.
There are already speed limit reduction trials in place on four section of UK motorway that have been identified among the sections where NOx levels are illegally high.
These are parts of the M32 near Bristol, the A1 at Blaydon, Tyneside, the M4 around Harlington, London, and the M621 in close proximity to Leeds, with most of these sections being cut by 10mph to 60mph.
Highways England suggested more trials were due to go ahead before the Covid-19 pandemic hit.
However, there is a counter argument for the surge in electric cars on British roads to pave the way for the limit to be increased by 10mph rather than reduced to cut journey times without impacting on pollution.
Transport Secretary, Grant Shapps, told a debate at the Conservative party conference last year: ‘On 80mph speed limits, I’ve been thinking about this issue and maybe even sought advice on the subject of late.
‘I think there is an argument for looking at our speed limits, both in terms of higher speed limits and actually lower limits – 20mph outside of schools.
‘When it was last looked at in 2011, reviewing the last submission to ministers on the subject, it was thought the carbon emission addition would be too great.’
Mr Shapps said being the owner of an electric car made him reconsider whether the emissions impact of an increased motorway speed limit would ‘still be the case’.
Specially-created electric forecourts are being built around the country to supply rapid charging solutions for plug-in car owners who are using their low-emission cars for long journeys
5. Arrival of new supercharging forecourts for electric vehicles
The first of a £1billion nationwide network of more than 100 custom-built electric forecourts opens this summer near Braintree in Essex, close to the M11 motorway.
The company behind the network, Gridserve, says it will charge 24 electric vehicles at once with superchargers that can deliver up to 350kW of charging power that will allow motorists to charge their vehicles within 20 to 30 minutes while they grab a coffee or do a bit of shopping, and much faster in the future as battery technologies mature.
It aims to have a full UK-wide network operational within five years on busy routes and near powerful grid connections close to towns, cities and major transport hubs.
The project has been backed by a £4.9million grant from Innovate UK and could see more pop up around busy motorways to supplement EV owners on extended journeys using the network.
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