Transport Insights

National Highways has continued its greenwashing of the Lower Thames Crossing but its pledge to wish away emissions from the construction of the unaffordable scheme is full of holes.

Last week the company claimed in a press release:

The project aims to cut its construction carbon footprint by 70% by aggressively targeting carbon as it refines the design of the new road and adopting new materials and methods of construction as they emerge. It has also made a legal commitment to responsibly offset any remaining carbon emissions using best practice, and only in the early 2030s once efforts to reduce it during construction are exhausted.

I have written extensively about how the government-owned company invented a purely notional figure for construction carbon emissions, which it now says it will cut by 70%. One part of this scam was to imagine that the project might not use ground-granulated blast furnace slag – a widely used lower carbon cement substitute – and then to claim a saving from deciding to use it after all.  

I also reported that, although National Highways claims to have carbon limits built into its contracts with the companies that will build the tunnel, it will not disclose what penalties will result from non-compliance, raising concerns that contractors may find it cheaper to pay the penalties.

National Highways has banned contractors from using offsetting to meet these targets but its Carbon and Energy Management Plan for the scheme does away with any claim that the targets represent any kind of a cut. It refers to “an upper limit for the use of carbon in construction, based on industry practice”, which implicitly admits that the original figure was using poor practice.

Contractors will also be incentivised to reduce emissions further towards a non-binding “stretch target”, but National Highways has also refused to say what these incentives are.

During the planning process, the company introduced a pledge to use offsetting to remove “residual” emissions – as long as this is not too expensive:

In line with best practice carbon management, the Applicant will implement an approach to carbon neutral construction, aligned to ISO 14068 by offsetting residual construction carbon emissions (CBN24). The Applicant will prioritise investment in carbon reduction solutions ahead of offsetting. This commitment can be amended by the Secretary of State on application in writing by the Applicant, where it is demonstrated to the Secretary of State’s satisfaction that residual construction carbon emissions cannot be responsibly offset for less than a mean average cost of £45/tCO2e (index linked to 2020 prices).

Alignment with ISO 14068 should mean that any offsets should be additional, permanent (carbon storage or removal) and verified, which is presumably what is meant by “responsibly offset”, but the whole pledge can be ditched if future ministers don’t want to pay for it.

A new report published this week describes any offsets not backed by permanent carbon removal and storage as “junk” and “a dangerous distraction from the real solution to climate change, which is rapid and sustained emission reduction”.

Academics at the University of Oxford and the University of Pennsylvania have conducted the most comprehensive review of evidence on the effectiveness on carbon offsetting to date and concluded the practice is ineffective and riddled with “intractable” problems.

It’s also a problem that any carbon removal to compensate for emissions that have already started will only happen in the next decade, with the carbon contributing to climate change in the meantime.

The main line of last week’s press release was however about cutting actual emissions:

The project is making early progress on its promise to carbon neutral as one of its worksites became the first ever to host the live deployment of a hydrogen powered digger anywhere in the world. A British-made JCB digger is being used by Skanska, the project’s delivery partner responsible for building the new road in Kent, to carry out ground investigation surveys around the route of the road near Gravesend.

The company says the project aims to eliminate diesel from its worksites by 2027 by making the largest ever purchase of green hydrogen for a construction project and using it alongside electric and biofuel to power its machinery.

It has so far failed to secure the hydrogen required, having first issued a procurement notice in 2023 and then again last year, when the first one failed. It now says a contract to supply, store and distribute hydrogen “is expected” to be awarded later this year.

The carbon saved will be a drop in the ocean compared to the emissions from building the scheme, not to mention the user carbon.

And really you wonder why they bother when the construction emissions can be wished away in an offsetting scam – forgotten altogether if it proves too expensive.