Interview to Luke Olly, Decarbonisation Manager at Holcim. Part of an article entitled within the article entitled: ‘Manufacturing progress’, published in ‘Materials World’, June 2025, pp.39-40,
What decarbonisation projects have you undertaken in recent years?
We launched our net-zero strategy in 2023 with a focus on five key areas – renewable energy, alternative materials, low-carbon fuels, carbon capture, utilisation and storage (CCUS), and energy efficiency and demand management. All these combined aims are to reduce our overall emissions to zero by 2050.
In 2024, we saw continued progress in our carbon emission reductions, with absolute Scope 1 and 2 emissions dropping a further 126,000t against 2023 performance, which is a 21% reduction and our lowest ever emissions per tonne of 15.1ktCO2.
Notable projects that have been implemented as part of this include the installation of rooftop solar panels at three UK sites with more in the pipeline. We have started to introduce electric vehicles to our fleet, with concrete mixer trucks in London and Birmingham, and an electric wheel loading shovel, with more to follow in 2025.
We have introduced the use of low-carbon fuels, such as sustainably sourced hydrotreated vegetable oil, to plant equipment and parts of our vehicle fleet to replace diesel, and have been increasing our use of rail to transport products.
We have pushed the use of alternative materials in our products, including a greater use of calcined clays, ground granulated blast furnace slag, pulverised fuel ash and biochar to help reduce embodied carbon content, and we have increased the use of recycled materials in our products from construction demolition materials. Where we
have used such alternative materials in our ready mix concrete in our ECOpact range, we can lower carbon content from anywhere from 20% upwards depending on the specifics of the mix and the application of the concrete.
Our waste heat recovery project, pioneered with Aston University, UK, has been rolled out to our asphalt plants after a successful pilot. This scheme sees waste heat generated as part of the production process is captured and recycled back into the process. It raises thermal efficiency, reducing fuel consumption and ultimately carbon emissions.
Our Dopplemayr conveyor system at our Bardon Hill Quarry uses ski-lift technology to deposit waste soils or overburden into our old quarry pit. The system can carry 1,000t an hour, reducing the need for road haulage and creating annual savings of over 1.4mln litres of diesel and 3,888t of CO2.
The Geocycle alternative waste facility at our Cauldon cement plant takes solid-derived fuels, which would otherwise go to landfill, and uses it as fuel to heat the cement kiln. This means we can take 100,000t of alternative fuel, reducing the usage of fossil fuels and reducing carbon emissions by 30,000t per annum.
Our future focus is on developing a large-scale CCUS plant at our Cauldon plant to capture carbon emissions generated as part of the cement-making process and carrying them by pipeline to be deposited safely in disused natural gas beds off the coast of Morecambe and Liverpool. This is part of the Peak Cluster project, which will help remove 40% of carbon emissions from the UK’s cement and lime industry.
We also have an ongoing focus on developing hydrogen as part of a UK-wide project to harness as an alternative clean fuel.
Have there been any economic benefits?
Many of these projects bring with them either greater efficiencies or, as in the case of solar for example, financial payback or savings in terms of power generated for site and the grid.
Projects such as our waste-heat recovery scheme and audits on energy efficiency and usage on sites wield savings in terms of wider energy costs to the business.
Potential savings on energy and fuel costs have longer term benefits.
In terms of sustainable products, there is a growing demand for these as developers, authorities and specifiers work towards making building and infrastructure projects more sustainable and lower in carbon.
Did these measures have any impact on your product range?
As part of our decarbonisation plans, we have developed key sustainable products with the objective of lowering embodied carbon content and increasing circularity. Our aim is to continue to grow the proportion of our sales that come just from sustainable products. In 2023, 31.4% of our total revenue was derived from sustainable products.
For example, our ECOPact and ECOPlanet products aim to use alternative materials in their mixes to reduce carbon. We also strive to use recycled content from construction demolition materials (CDM) within our products. There is ongoing development in this area using various different approaches to achieve this, while working within the various standards and codes in the UK.
All products within the ECOCycle range contain 10-100% CDM, created via the efficient distribution, processing, grinding and recycling of CDM into new building solutions, with no compromise on performance. By recycling CDM and reusing it in new products, we can preserve natural resources for longer.
The ECOCycle labels are verified with ISO 14021 standard. The contribution we’re making to accelerate the shift to a circular economy is fully verified and validated to the highest standard.
We have also partnered with Swiss clean-tech start-up neustark to introduce its carbon-removal technology to the UK. It captures CO2 from biomass sites, liquefies it, before injection into processed demolished concrete for new concrete production, storing on average 10kg of CO, per tonne of demolished concrete. Our ECOPact Recarb product is made up of recycled concrete which has undergone the neustark process.
In our asphalt business, we recycle old road surfaces, known as RAP, to use when creating new products, meaning fewer virgin materials are used.
What learnings have you applied across other locations or parts of your business?
With many of our projects, they start out as ideas or small-scale pilots at a specific site as part of our ongoing innovation workstreams cycle. We look to test small first so we can develop the learnings, as often we are trialling new technology which may require certain funding requirements, legal processes, and adherence to standards and procedures.
We will look at what is involved, at the different technologies available, what suppliers
there are and test it.
Once we are satisfied and we have developed a sense of what works best, is efficient and can make an evidenced difference, we will look to upscale that gradually and roll out to multiple sites, or in some cases the rest of the business.
Examples of this can be seen in our waste heat recovery project, solar schemes, alternative fuels and low-energy lighting projects.
What policy or regulation changes would you like to see to make these commitments easier for businesses like yours?
For us there are two key areas of policy would like further clarity and support on from the government.
Clarity on the phase-down for the Emissions Trading Scheme (ETS) over the next five-to-10 years. The implementation of the Carbon Border Adjustment Mechanism and the implementation of a robust process to protect the UK markets.
We also need to ensure, where possible, we are closely aligned to our EU counterparts to ensure the UK does not become an isolated market when it comes to decarbonisation and it to investors and funders.
What advice would you give to other manufacturers who are wondering how to begin decarbonising?
In general terms, decarbonisation is related to a change in technology that is available.
Changes in fuel, processes or efficiencies can only get you so far in your journey.
You need to be open to change and innovation, then be willing to invest in that change. You have to be willing to change the way you operate and to be adaptive.