Carbon Expert of the Month December 2021

What led you to become a construction carbon expert?

I have a civil engineering background. I started my career at ArcelorMittal working on structural fire engineering projects – which became my field of expertise. Earlier this year my position evolved to include a focus on LCA and carbon assessments. In the current climate change context we’re facing and knowing the important share construction has in worldwide carbon emissions, it is crucial to act, as an engineer, regarding both the material production process and how we design buildings.

 In the end, this may seem like an unusual career trajectory, but I think (and hope)  – that most engineers will follow a similar path in the years to come: even if our background is not in the strictest sense linked to environmental science, we cannot overlook the environmental impact of construction anymore.

What kind of projects do you typically work on, and in what role?

Within the Steligence Engineering department, we provide technical assistance to design offices, architects, project owners and investors to help them optimise their projects. The goal is to take a holistic approach for each of the projects and to get the best steel solutions keeping an intelligent combination of materials, i.e. considering several criteria such as the execution rapidity, the flexibility of use, the cost, and of course the environmental impact.

Within our department, we all have a structural engineering background, but each of us with his/her area of expertise. As far as I’m concerned, I mainly provide support regarding fire and sustainability aspects. For example, I perform upstream and downstream analyses for EPDs, help customers in interpreting such documents, and use them to conduct LCA analyses for their buildings. I therefore bring support to propose steel-based solutions with low embodied carbon.

Which projects and achievements are you the proudest of?

This year, we have launched the XCarb® brand, designed to bring together all of ArcelorMittal’s reduced-, low- and zero-carbon products and steelmaking activities, as well as wider initiatives and green innovation projects, into a single effort focused on achieving demonstrable progress towards carbon neutral steel.

Given the wide and challenging scope of XCarb®, many people were involved – at different levels and for different aspects. I feel proud to have taken part – and to continue taking part, alongside my colleagues – in such a meaningful project.

How do you see carbon performance evolving on the market?

From my personal experience, the market is getting more and more aware of the global issues at stake, and the demand for greener construction is growing. 

But it takes extra effort and some time to go from a good intention to a real application/action. 

In some countries, regulations are in place (or being put in place) to enforce carbon reductions in buildings and infrastructures. But in other ones, it is not yet the case: the environmental impact remains a “nice to have” aspect on top of other concerns. 

As engineers, I believe we have an important role to increase the awareness on the market, but if the relevant authorities do not support the global effort by implementing concrete plans, it makes progress much more difficult.

What are the key value drivers you use to make the business case for materials carbon?

Choosing a low embodied carbon material is important but not sufficient – such an initiative should be combined with an intelligent design which adds more carbon savings. A key concept that should be followed by architects and structural engineers is the “refurbish – reuse – reduce – recycle” hierarchy.

 The “refurbishment” axis is a very effective means of reducing demand for construction materials (and therefore related embodied carbon), and the “reduce” step can be emphasised while properly selecting the building’s grid: it should play to the strengths of the material being used, while favouring a holistic approach. “The right material at the right place” is a concept we try to emphasize in our daily activities.

How does your engagement on materials sustainability vary over project phases?

ArcelorMittal is the world’s leading steel company and is committed to reaching net-zero on a global basis by 2050. We have now adopted a set of carbon targets: by 2030, we are targeting a 25% reduction in our CO2 emissions intensity across our global operations, with a European target of 35%. As construction products manufacturer, our main role is therefore at the very beginning of the chain.

In my case, as Steligence Engineer, it is in the upstream part of the construction chain that my involvement is the most effective. Indeed, it’s at the early phases and (pre-)design phase that my colleagues and I can reach an optimal situation. Nevertheless, we are sometimes asked to participate in later stages of construction projects – and we of course do our best to provide the most relevant solution.

What level of embodied carbon reductions are your projects achieving today?

XCarb® serves as demonstrable evidence of our determination and accelerating commitment to achieve carbon neutrality by 2050. We will continue to drive innovation to meet our decarbonisation goals and are committed to leading the industry transition towards carbon neutral steel. We have the scale, resources, technology prowess and ambition required make a significant impact.

One part of XCarb® is the “XCarb® recycled and renewably produced” label which applies to products made via the Electric Arc Furnace route recycling scrap steel and using 100% renewable energy. By using only scrap steel and renewable energy, XCarb® recycled and renewably produced products have a low CO2 footprint. For example, we published earlier this year the first XCarb® recycled and renewably produced EPD for sections and merchant bars, with a GWP of 333kg CO2eq/t for modules [A1-A3]. 

Coming back to Steligence, we develop cases studies for a given building and a given occupancy. Several designs are prepared by independent and external third parties, and we then compare these “baseline” designs with our “best-in-class” steel-based design based on several criteria such as the cost, the speed of construction, the flexibility and of course, the environmental impact. Combining low carbon steel structural elements with an intelligent design allows us to bring a significant carbon reduction in a building: up to 50% reduction can be achieved.

Which best practises or lessons have helped you the most in this work?

To gain perspective on situations.

Within ArcelorMittal’s Steligence department, our main driver is to bring a holistic approach in construction. People usually focus on a narrow object or part of a situation, or on short-term matters, forgetting to look at the “big picture”, which leads them to erroneous judgments.

In the specific case of construction, we should always remember to look at the project as a whole. This philosophy is in line with the LCA approach – capturing the full system, all along its lifespan. 

For example, we too often witness people comparing 1kg of wood with 1kg of concrete with 1kg of steel. They forget there must be an equivalent functionality to allow the comparison.  As the structural materials present different mechanical and thermal properties, they will lead to different designs for a given purpose. It also happens that people forget about the recyclability and reusability potential of the structural systems.

More globally speaking, I personally believe gaining perspective helps to solve many issues.

How does One Click LCA help you achieve your goals?

One Click LCA offers both an easy-to-use and a comprehensive tool to analyze our projects, allowing us to follow different methodologies and approaches. Quick yet reliable upstream investigations can be carried out – allowing for example sensitivity analyses, identification of CO2 hotspots in the project making it much easier to optimize designs. 

One Click LCA has the advantage of being both comprehensive (up to date EPD database covering several EPD publishers, possibility to apply different methodologies) and easy-to-use (the user can directly compare several design options and customize his/her reporting).

In addition, One Click LCA provides an excellent customer support (providing on demand trainings) as well as helpful (and timely) technical content to help the users understanding the scientific and normative background.

Last but not least, I believe the link with BIM is a significant added value.