The last week’s Emissions Gap Report 2024 from UNEP (UN Environment Programme) makes for disturbing reading.
While the report says it is still technically possible to meet the 1.5°C goal, this can only succeed with a G20-led massive global mobilisation to cut all greenhouse gas emissions, starting today.
The buildings and construction sector which accounts for 37% of global emissions, is at a critical juncture, challenged to decarbonise in the face of rapidly escalating demand for cement and concrete across the globe. One of the largest contributors to the industry’s emissions is cement – accounting for almost 8% of global CO2 alone. According to the International Energy Agency (IEA), there needs to be an annual 3% reduction in the industry’s emissions to align with the Net Zero scenario.
Given all this, we need to adopt the widest possible range of viable, emerging technologies as fast as we can, if we are to stand a chance of meeting the Paris Agreement’s 2030 target. We cannot afford to focus on one technology only. Now it’s time to pull all the levers we can: altering construction processes, moving to low-carbon construction materials and, after these routes have been exhausted, capturing the residual emissions.
There are immediate opportunities available in the form of clinker substitution technologies, which can rapidly decarbonise the cement industry at scale today. With the right multi-solution approach in place, we could achieve success in cement decarbonisation and move a lot closer to decarbonising the construction sector within this decade.
Currently, policy is almost exclusively directing the cement industry towards Carbon Capture, Utilisation and Storage (CCUS) technology as the de facto decarbonisation strategy for the cement industry. Yet data proves that these approaches face significant economic and practical challenges.
First of all, CCUS is exceptionally expensive. On average, it will cost between €300-500 million to equip and operate new CCUS facilities at existing European cement plants. Considering there are over 200 such plants in Europe, this adds up to an extraordinary and unrealistic investment amount.
Secondly, given many of these plants are landlocked, with no obvious storage or utilisation outlets, the logistical constraints associated with dealing with the captured carbon means it will be decades before this technology makes an impact. Decades that we don’t have.
The climate emergency demands that we prioritise rapid decarbonisation now. The most effective way of doing so is to use cement more efficiently than it is used today. Cement and concrete technology has advanced significantly in recent years, making it possible to use half the amount of cement in concrete compared with historical levels, while still maintaining essential performance metrics. Halving the amount of cement produced means halving the CO2 associated with cement production.
We can reduce the industry’s footprint even further beyond the 50% threshold, by maximising the use of locally available alternative materials, known as Supplementary Cementitious Materials (SCMs). The more SCMs we incorporate, the greater the positive impact will be
Low-carbon cement is not new. What is new is the ability to scale these cements using a variety of readily available SCMs. Industry reluctance to engage with these solutions has been rooted in the belief that there are not sufficient volumes of these SCMs available to make a real impact.
Low-carbon SCMs such as GGBS, Calcined Clays and Natural Pozzolans can be used to reduce cement content today, which can result in a scalable 70% reduction in the cement industry’s carbon footprint. Some SCMs, like GGBS are likely to disappear in future because of industry decarbonisation in other sectors such as steel- alternative SCMs need to be developed to take their place. As an industry and as a society, we need to accelerate developing and valorising SCMs for use in cement and concrete with much greater urgency than we are doing today.
The Alliance for Low-Carbon Cement & Concrete (ALCCC) has already shown that there are almost 20 SCMs available, the annual volume of which could exceed the quantity of conventional cement produced globally each year. When used in an efficient way these low-cost, locally available products can be used to scale significant CO2 reduction across the entire cement industry.
Using cement more efficiently and accelerating the development and deployment of low-carbon SCMs are two essential steps for effective decarbonisation. Allocating even a fraction of the funds currently directed toward CCUS through policy could yield substantial short- and long-term decarbonisation benefits, ultimately reducing the heavy reliance on CCUS alone.
This is what makes Ecocem’s ACT technology so exciting for the industry. It is scalable, allows for high-efficiency use of cement in concrete, whilst deploying a range of locally available SCMs to achieve major decarbonisation on a cost competitive basis. And it can be produced today at most existing plants, without the need for expensive upgrades.
There remain challenges to scaling up technologies like ACT at the speed necessary to deliver emissions reductions we require. To achieve this, we need to focus on three key areas:
It is imperative that we embrace a diverse range of solutions, supported by appropriate policies and funding, to achieve a sustainable and economically viable path to decarbonisation.
To quote António Guterres, UN Secretary-General, “…affordable, existing technologies can achieve the emissions reductions we need to 2030 and 2035 to meet the 1.5-degree limit… Closing the emissions gap means closing the ambition gap, the implementation gap and the finance gap.”
Ecocem, Europe’s leading provider of low carbon cement technologies, has joined other prominent businesses in calling for the UK Government to reassert the country’s global climate leadership position at COP29.
As part of the Contracts for Innovation: Decarbonising Concrete competition, Innovate UK has decided to fund a demonstrator project using our ACT low-carbon cement technology on a live job site at Wembley Park, UK.