Philip Haigh
PHILIP HAIGH examines a new report on High Speed 2’s carbon impact, which concludes that the line will be a key contributor to plans for a greener future
“More subtly, HS2 needs to take those on rail today onto its tracks, to create the space for those in cars to switch to rail for journeys on the classic network. There’s also scope for freight to dump lorries in favour of trains.”
ARGUMENTS rage back and forward about High Speed 2 - not least about its environmental impact.
Some aspects are clear. Rail travel generally emits lower levels of carbon than taking the car. It certainly performs better than air travel.
It’s also true that pouring concrete, smelting iron ore or producing steel emits carbon. Therefore, building HS2 from London to Birmingham and then onwards to Manchester and Leeds will emit carbon, as will building the trains that will ply the line.
This means that HS2’s overall environmental performance depends on how people change their travel patterns. It needs to convince those flying from Scotland to London to switch to rail. It needs to encourage the London-Birmingham traveller to forsake the motorways in favour of rail.
More subtly, HS2 needs to take those on rail today onto its tracks, to create the space for those in cars to switch to rail for journeys on the classic network. There’s also scope for freight to dump lorries in favour of trains.
And, yes, perhaps cars’ environmental performance will continue to improve if electric versions become more popular and capable. But that’s not a reason to ditch or delay HS2, because it means that overall transport in Britain becomes greener.
Note, too, that increasing numbers of electric cars will consume more minerals. A letter last summer from the Natural
History Museum to the Climate Change Commission claimed that for Britain to meet its 2050 electric car target, it would need just under twice the current total annual world cobalt production, nearly the entire world production of neodymium, three-quarters of the world’s lithium production, and at least half of the world’s copper production.
To shed some light on the debate, the High Speed Rail Industry Leaders (HSRIL) commissioned a report to look at the issue more closely ( RAIL 892).
Its author is Ralph Smyth, who was head of infrastructure and legal at CPRE, the charity formally known as the Campaign to Protect Rural England. The report notes that Smyth was the only person allowed to petition against HS2 legislation on its climate change aspects.
HSRIL itself is an umbrella organisation, open to companies to join. It currently includes train builders such as Alstom, Bombardier, Hitachi and Siemens, and civil engineering contractors such as Bouyges, Costain, Laing O’Rourke and Murphy.
In the foreword to the report, HSRIL writes: “The HS2 project will - in fact, must - form a crucial part of the transition to net zero. The UK’s answer to the emission reduction challenge in the transport sector must be an irreversible shift to low-emission mobility, and HS2, as a high-capacity fully electrified railway, is key to making this happen.”
It argues that HS2 is already doing better in terms of carbon impact, with savings found on its preparatory works. It claims that HS2 is vital if Britain’s transport sector is to decarbonise, that
HS2 can play a key strategic role in climate change, and that any temptation to curtail the project will weaken its carbon case.
It claims: “UK carbon emissions from transport are still increasing and have recently become the country’s single largest source of carbon emissions. Only a new electrified railway has the capacity to attract substantial travel volumes from road and air, and enable rail to become the longer-distance mode of choice.
“In light of these facts and the challenge of the new 2050 target, it is plain that investing in HS2 should be a central plank of the Government’s forthcoming Transport Decarbonisation Strategy. HS2 services will launch with largely de-carbonised electrical power generation with a rapid path to zero emissions ahead. HS2 has an unassailable case to be part of Britain’s net zero future.”
Smyth makes ten recommendations. They include resetting and relaunching HS2’s environmental narrative so that it aligns with the country’s net zero carbon ambition, as it did to 2008’s Climate Change Act when it was launched a decade ago.
He suggests that in building HS2, the project should continue to include challenging targets for carbon reduction. He notes that this could provide Britain with a chance to position itself as a global leader for green building, which could help attract young people into the sector.
Smyth calls for HS2 to commit to using zero carbon electricity from its first year running, and for it to have a track access regime that sets charges just above marginal rate for traffic that has high potential to attract people from roads and planes but might not be otherwise economical to run.
Transport has its own hierarchy akin to the more familiar ‘reduce, reuse, recycle’, which is to minimise demand, enable modal shift, optimise system efficiency and increase capacity (in declining order of sustainability).
With most travel by car, Smyth notes that efforts to reduce it (perhaps by road-charging) will increase rail demand. And with two of Britain’s most crowded motorways stretching between London and Birmingham, it’s reasonable to assume increased rail demand on this corridor.
Even if cars become electric, their average occupancy lags behind rail for the space they occupy - making rail the more efficient system for moving large numbers of people. In turn, if Britain is to increase transport capacity, then rail has the advantage because it consumes less land than roads.
Estimates for HS2 construction emissions have increased sharply
since the first estimate of an equivalent carbon dioxide (CO e) figure of 1.2Mt for Phase 1 (London-Birmingham). By 2013, they were 5.5Mt as a result of more conservative estimates, and they rose again after more of the line through the Chilterns was placed into tunnels to mitigate their visual impact. In 2019, the estimate stands at 6Mt.
HS2 now has stretch targets to cut carbon emissions from its main works civil engineering contracts by 50%. Smyth reckons that an overall cut of 20%-30% is possible.
Contractor Eiffage Kier has cut the carbon footprint of green tunnels by 39% and viaducts in one area by 49%, by using precast recycled concrete in place of steel girders. Elsewhere, design contractor Align has cut Colne Valley Viaduct’s carbon footprint by 28% by redesigning it to a stronger, simpler design, according to Smyth’s report.
He also cites a report by Greener Journeys to suggest that the carbon footprint of Phase 1 and 2A (to Crewe) is only 50% greater than the impact of freezing fuel duty since 2010.
Noting that the project’s greatest areas of carbon emissions come from the steel for its tracks, followed by concrete, Smyth reckons that the loss of mature woodland only represents only about 2% of the total carbon impact.
Once trains are running, HS2’s carbon footprint consists mainly of its electricity supply for traction. Smyth records that Britain’s power grid is decarbonising faster than anticipated, and that HS2’s delayed opening means that the grid will be largely decarbonised.
“This means the question of HS2 operating speed - and the consequential energy requirements - is largely irrelevant to the calculation of the project’s carbon impacts,” he says.
With Douglas Oakervee’s report into HS2 only leaked rather than published, Smyth comments on some aspects being promoted as alternatives for HS2.
He dismisses suggestions that the line should be terminated at Old Oak Common rather than pushing its tunnels on to Euston. This would prevent significant change to services on today’s line, such as strengthening local trains or running more freight. In addition, today’s air passengers are as likely to keep travelling to their out-oftown London airport as they are to out-of-town Old Oak Common, he argues.
“Cutting the network short could also reduce the benefits for urban regeneration and increase pressure to develop in the Green Belt. In short, such a change would be very harmful to the generation of carbon benefits from HS2,” Smyth suggests.
As for the alternative idea of upgrading current lines rather than building HS2, Smyth argues: “Due to their weak strategic case, upgrades were not scoped in detail to enable their carbon footprints to be compared with HS2. But given HS2’s efficiency in unlocking capacity on the conventional railway network by segregating non-stop trains, it is very unlikely that an upgrade approach would produce the operational carbon benefits that stem from the HS2 project.”
He continues: “And there is no reason to suppose that changing HS2’s alignment would result in any significant change in carbon impacts, unless the replacement route abandoned sections of tunnelling as a local environmental impact mitigation measure.”
In switching Britain to a netzero carbon economy, Smyth’s report puts forward a clear case for HS2. But he notes that there’s more work to be done to look at improving the existing railway north of Manchester to Scotland, and to consider the potential for high-speed freight.
He finishes by saying: “HS2 would offer significantly greater resilience than existing railways and, with extreme weather becoming more prevalent, its key role as infrastructure for climate adaptation should be given more attention.”
“Even if cars become electric, their average occupancy lags behind rail for the space they occupy - making rail the more efficient system for moving large numbers of people. In turn, if Britain is to increase transport capacity, then rail has the advantage because it consumes less land than roads.”