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120 years to carbon neutrality?

We often hear from Greens, including very senior ones, that HS2 is a climate disaster because it won’t be CO2-neutral for a long time. “120 years!” is quoted, “HS2’s own figures!” One big problem with this: it isn’t true.

Let’s take a look at HS2 and CO2.

HS2’s official position is that after 60 years HS2 will either be slightly CO2-negative (if construction doesn’t improve its CO2 efficiency) or slightly CO2-positive (if it does). The Oakervee review covers this – sections 5.30 to 5.37.

The modelling is covered in more detail here. We’ve extracted the numbers below from that.

They consider two future scenarios. Scenario A, in which electric car adoption and grid decarbonisation happen slowly, and a more optimistic Scenario B. These charts summarise both.

Scenario B, with no improvements to construction emissions
Scenario B, including improvements to construction emissions

In red are things that emit GHG (mostly construction and operations) and in green things that save them (mostly passengers and freight shifting from other modes). The final column shows the net position after 60 years.

We’ve shown the numbers for “Scenario B” – faster decarbonisation of the electricity grid and introduction of electric cars. The two charts show the without- and with-improvement of construction cases.

Results: without improvement: net production 1.2 mTCO2e; with, net gain 4 mT.

(From work already done on HS2, we know that the actual construction emissions will probably be nearer the with-improvement case. @safemyth’s report – good read, recommended! – describes this.)

So over 60 years HS2 will be pretty much CO2 neutral, going by HS2’s own calculations. Just to give a sense of scale, even the no-improvement case is equivalent to less than 4 days’ worth of current UK road transport emissions!

But there’s more…

Let’s have another look at where the CO2 savings come from. The main win comes from trips that would have been done by air shifting to HS2. Next is getting lorries off the road, by having more rail freight on freed-up lines.

One important thing to note here is that HS2’s forecasts of where HS2 passengers will come from show just 1% of them switching from air and 4% from car.

These are ridiculously low compared to what has actually happened with high speed rail elsewhere. Why is this?

The forecast method is known to be weak. It specifically excludes any factors that would favour rail over car or air. Mainland Europe high-speed rail has much higher from-air percentage. Even so, those few air passengers switching make a huge difference to carbon emissions.

Imagine if we could double that share coming from air – that would be a massive CO2 win! Easily doable with Green transport policies: air taxes, frequent flyer levy, slot recapture, additional rail fare subsidies. without all of these policie

Plus: all those passengers coming from existing rail are freeing up vital space on the network for new local train services. With Green policy support, these trains can get thousands of people every day off the roads – another CO2 win, one not included in any of the figures.

(The plans for exactly what to do with all that freed-up space are still being developed, but Midlands Connect have ambitious ones, as do Transport for the North. Green policies would maximise the benefits to local people and CO2 savings from this.)

It’s hard to estimate exactly what the CO2 impact of Green policies could be on modal shift, both on and off HS2. It’s fair to say, though, that dismissing HS2 as a CO2 disaster is wrong: it’s a huge opportunity.

And what about that “120 years” thing? Well, the HS2 figures actually show that in years 61-120 an additional 8.2 million tonnes of CO2 could be saved. So the overall picture looks like this chart – a CO2 gain of over 12 million tonnes over the life of HS2!

That so many Greens parrot the fake 120-years line without question shows how poorly thought-through the party’s stance is.

For a start, as we’ve shown, it’s not based on fact. It’s spin by the ‘Stop HS2’ campaign, repeated verbatim by lazy commentators (and politicians) who don’t check.

Secondly, where’s the critical thought? Why are we not questioning so bald a statement? We should be asking what do we mean by “CO2 neutral”, what are the assumptions behind that number, how has it been calculated, what are the sources and can we trust them?

Thirdly, where’s the holistic thinking? Greens are supposed to be all about understanding the linkages and connectedness of all things. How can we just accept that something as fundamental as the CO2 impact of a transport scheme isn’t affected by a whole range of influences?

And finally, just stating it as fixed in stone betrays a complete failure to grasp how our own policies can impact HS2’s CO2 and how we can turn it to our advantage – a shocking lack of political ambition.

So, a sorry tale of ignorance and naivety completely at odds with Green principles. To tackle transport CO2 we need radical change. Tinkering isn’t going to cut it at all. We’re bold and radical in other policy areas – why not be equally bold and use HS2 to further our own goals?

Addendum: what’s included in HS2’s CO2 modelling? We keep hearing that some source or other of CO2 is left out so the figures are suspect. Here, taken from the document that describes the modelling, is a list of what’s included:

☑️ Earthworks
☑️ Embankments and cuttings
☑️ Disposal of waste material
☑️ Change of land use (= clearing of trees and other vegetation)
☑️ Bridges and viaducts
☑️ Access and haul roads
☑️ Retaining walls
☑️ Tunnels
☑️ Tunnel boring machine operation
☑️ Stations and depots
☑️ Trains

For each of these categories, the calculation includes materials, transport of materials and people, and equipment.

Operational CO2 comes from:

☑️ Train electricity
☑️ Station electricity
☑️ Tunnel fans electricity
☑️ Maintenance of trains

Most things seem to be covered!

Addendum 2: This brilliant piece of work by David Peilow completely explodes the 120-year myth, suggesting HS2 could be CO2-neutral in as little as 28 years depending on policy moves. Check it out on Twitter below: