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Live Labs 2 blog - Unpacking the carbon question

This month’s blog is from Giles Perkins, Programme Director for Live Labs 2. Giles talks about sustainable infrastructure, carbon focused innovations and the Live Labs 2 programme.

At the heart of Live Labs 2 are two fundamentals. The first, to evidence in absolute terms, how carbon focused innovations across the highways sector can reduce its embodied and operational impacts (rather than user / tailpipe). The second, to encourage behaviour change and adoption of such techniques across industry.

Measuring impact

Measuring the true carbon saved through new products, process and systems is critical in reducing the impact of new infrastructure, the maintenance of existing and ultimately the impacts of decommissioning. 

The deep evidencing of carbon benefits was something we wanted to intellectually stretch in Live Labs 2, as traditionally the transport sector focus has been on tailpipe (user) carbon emissions. This is instead of thinking through the embodied and operational emissions associated with creating and maintaining the networks for use by people and freight over many decades.

Unveiling carbon intricacies

The Department for Transport's Transport Advisory Guidance (known as TAG, which is used for appraisal) unit A3 was updated relatively recently to include Whole Life Carbon measurement in 4.2.10: “to support the consideration of schemes’ WLC impacts, it is recommended that, where feasible, proportionate whole life carbon assessments are conducted in accordance with the principles of the PAS 2080”. 

Additionally, 4.2.11 was added: “the whole life carbon (WLC) impacts of a scheme include capital carbon (emissions associated with scheme construction), operational carbon (emissions associated with scheme operation and maintenance)”.

As part of the development of the ‘Strategic Outline Business Cases’ (SOBCs) that each of the seven successful Live Labs 2 cohort submitted, we developed an additional carbon case, distinct from the activities that TAG required, to provide greater rigour. 

We asked our cohort two questions;

  1. The expected carbon benefits and estimated carbon impact, as per the spirit of Tag Unit A3.
  2. To detail their approach to the measurement of all carbon scopes / lifecycle associated with their proposal proposed tools, methodologies and source data. 

Both are important as we wanted to go beyond the ‘proportionate’ ask as whilst each live lab is relatively modest in its scale (compared to major infrastructure projects) given our laser sharp focus on the subject.

Rigorous baseline assessments: diversity in calculation approaches

Each live lab provided initial baseline estimates (depending upon their varied interventions) of the potential carbon reductions supported by their methodologies. 

A large proportion are using the Future Highways Research Group Carbon Calculation & Reporting Guidance for Local Highways Authorities, some supplementing this with additional academic and industrial datasets. 

Others are using consultant led tools, and one live lab is building data from the bottom up with academic support.

Tackling data variability

This deep dive is already starting to reveal some interesting facts. As measurement techniques mature and becoming more rigorous, we are converging to a more robust understanding of what the carbon impacts of interventions could be. 

For instance, the Devon County Council Live Labs 2 project covers the A382 Jetty Marsh Link, an Early Contractor Involvement (ECI) scheme which Live Labs 2 is funding low carbon solutions and assessing these against the traditional baseline. 

The initial calculation of carbon baseline undertaken at the early design stage in 2021 gave an estimate of 7776tCO2e -this has now matured to 10729 tCO2e (as of December 2023) as the scheme has progressed through the ECI process. A more detailed breakdown is below.

A382 carbon baseline Live Labs 2

Our live labs are all completing their carbon baseline work, which we will be publishing in due course. This data covers all aspects of the activities associated with their programmes and will be used as the measure against which overall carbon savings will be calculated. 

It is obvious that rigour is critical in these activities and a convergence to a consistent approach is an imperative in comparing interventions and benefits in a like-for-like way.

Variability in carbon calculations of Environmental Product Declarations

As we’ve progressed on this journey, we’ve uncovered huge variability in the way in which carbon calculations are being handled in Environmental Product Declarations (EPDs), which provide information about the environmental and sustainable attributes of a given product. 

This presents a confidence challenge in understanding the carbon impacts of the materials and products which will be part of our Live Lab 2 interventions. To tackle this, we are developing an approach to filtering data and provide us with confidence on underlying assumptions.

As an illustration, think about a lighting column that might be part of our East Riding Live Lab. The column, the luminaire, the internal cabling, the foundation, the groundworks and its connection to the grid all have carbon impacts. Some will be during manufacture, the energy used, materials, processing and manufacturing, similarly any products or sub-assemblies will have transportation impacts, which will vary hugely if the origin is the UK, versus say Europe of further afield. 

Where and how those EPDs are calculated, and underlying data therein, is critical in feeding into our calculations.

Live Labs 2 image

System thinking for future strategy

Thinking about carbon impacts as a system raises wider considerations and touches upon future industrial strategy needs. For example, aggregates which are sourced more locally to a scheme will have reduced transportation costs and, domestic steel, perhaps produced by sustainable means will have reduced impacts than globally sourced, blast furnace steel.

Converging to a robust and consistent way of measuring the carbon impacts across the sector provides us with a potential additional lens to consider competing schemes with a programme or across a region or territory.

By using a suitably robust and standardised whole life carbon saving metric (for the infrastructure) as a differentiator alongside the usual Benefit-Cost Ratio (BCR) we could make more nuanced decisions. 

For instance, two projects competing for funds within a programme which both pass a high bar stage gate with exceeding say a BCR of 3:1 could be differentiated with their carbon saving. A lesser performing scheme, which had passed the stage gate, could therefore go forward as its carbon saving might be much greater than its competitor. 

Extending thinking further, if carbon budgets were associated with investment programmes, understanding how schemes would use those budgets become an imperative. Obviously, carbon can be one of many factors and indeed TAG Unit A3 helpfully illustrates in its Appendix D similar thinking exploring cost, social and carbon impacts.

Exploring carbon equity in policies: harmonising approaches for local roads

Such thinking isn’t necessarily new. By integrating health equity into all policies, the city of Coventry through their ‘Marmot City’ approach has shaped service commissioning, location decisions and priority areas for action, with evidence from the monitoring programme influencing strategic resource allocation. With the pressures we face in reducing carbon emissions across all scopes, taking a similar carbon- equity approach could be extremely beneficial.

Live Labs 2 is exploring these concepts with a view to harmonising approaches for the benefit of the UK local roads sector, to accelerate capital carbon savings, change behaviours and deliver accelerated outcomes.

The Live Labs 2 Expo will be taking place on the 17th April in Birmingham, showcasing insights, innovations and collaboration across the programme. We’ll be discussing the programme in greater details – we hope to see you there.

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