Cement

Countries and regions making important notable progress in decarbonising cement production include the following:  

• In the United States, the Inflation Reduction Act, announced in August 2022, set out a budget of USD 5.8 billion for industrial decarbonisation to support the reduction of around 200 Mt of CO₂ – 17% of the total estimated emissions reduction envisaged by the Act – by 2030. An update to the 45Q tax credit for industrial applications of CCS, and investments in CCS demonstrations and CO2 transportation infrastructure should help to abate emissions from the cement sector. 
• The European Union released its Green Deal Industrial Plan in February 2023. The Plan aims to simplify, accelerate and align incentives to preserve the competitiveness and attractiveness of the EU as an investment location for net zero industries, but specific measures to support the transition in energy-intensive industries such as cement have not yet been developed.
• In China, the Ministries of Industry and Information Technology, National Development and Reform Commission, of Ecology and Environment, and of Housing and Urban-Rural Development launched the Carbon Peak Implementation Plan for Building Materials Industry in November 2022. Focusing on the cement and lime industries, the plan sees carbon emissions peaking before 2030 through continuous development and deployment of low-carbon materials and technology, reduction in energy consumption, and the transition to clean and green energy. 
• The Netherlands, Sweden, Germany, France, the United Kingdom and the United States were identified in a policy analysis by the World Economic Forum and the Global Cement and Concrete Association (GCGA) as frontrunners in the adoption of regulation on low carbon concrete and construction, and implementation of supporting public procurement schemes.
  

Cement emissions intensity has remained relatively stable since 2018, at just under 0.6 t CO₂ per tonne of cement produced, following several years of modest increase largely due to an increasing clinker-to-cement ratio in China.

To get on track with the NZE Scenario, emissions must fall by an average of 3% annually through to 2030. Energy and material efficiency improvements, adoption of low-carbon fuels, clinker substitution and innovative near zero emissions production routes will be key to achieving this objective. The development and deployment of technologies not currently commercially available will also be required, with investment being critical to ensure these technologies are available at scale within the near term.

From 2010 to 2020, the average thermal energy intensity of clinker decreased by 0.2% annually and has since remained relatively flat at about 3.6 GJ/t clinker. This decrease was alongside an increase in the sector's electricity intensity, which reached around 100 kWh/t cement in 2022. The NZE Scenario sees average thermal energy and electricity intensities reach less than 3.4 GJ/t clinker and 90 kWh/t cement, respectively, by 2030, excluding additional energy required for the deployment of emission reduction technologies such as carbon capture, which come with a penalty in terms of thermal fuels and electricity consumption. For example, CCUS technologies add around 5 kWh/t cement to the global average electricity intensity. 

Fossil fuels continued to be the main source of thermal energy for the sector (90% share) in 2022, followed by bioenergy and renewable waste (4%) and non-renewable waste (4%). The adoption of low carbon fuels is key to reduce the share of fossil fuels to 79% and non-renewable waste to 3% by 2030 in line with the NZE Scenario, which sees bioenergy and renewable waste increasing to 16% and hydrogen to 2% of the total thermal energy share.

Cement production declined significantly in 2022, down 5% to 4 158 Mt. But this number hides contrasting regional trends. Despite the decrease in production in China (-10.5% year-on-year), as a result of the country's real estate crisis and policies to respond to the coronavirus pandemic, China remains the leading global cement producer, representing 51% of global production.  

India strengthened its position as the second largest cement producer in 2022, with the country’s share of global production rising from 8% in 2021 to 9%. Over the longer-term, declining production in China is expected to be offset by production increases in Southeast Asia, Latin America and Africa to meet their development needs.  

Global cement production must stay relatively flat through to 2030 to align with the NZE Scenario. Material efficiency strategies, such as resource-efficient manufacturing, promoting material efficiency in construction by avoiding overdesign and maximising the lifetimes of buildings and infrastructure, are critical to reducing cement demand.

Emissions from manufacturing clinker – the main component of cement – result from chemical reactions and fuel combustion in the process. Measures to reduce emissions include reduction of the clinker-to-cement ratio through the adoption of supplementary cement materials (SCMs), adoption of low-carbon fuels, and capture of residual CO₂ emissions.

The global clinker-to-cement ratio¹ has increased at an annual average of 1.1% since 2015, from 0.66 increasing to 0.71 in 2022. This number hides significantly different regional trends. China, despite having one of the lowest clinker-to-cement ratios globally, saw an increase from 0.57 in 2015 to 0.65 in 2022. In contrast, countries with high ratios such as the United States and Canada have decreased their ratios from 0.90 and 0.87 in 2015, respectively, to 0.89 and 0.86 in 2022. To align with the NZE Scenario the ratio must decrease 1.2% annually to a global average of 0.65 by 2030. To enable this, it will likely be necessary to revise standards such as building codes in some regions, to focus on performance of concrete rather than prescriptive composition-based requirements, while considering regional circumstances and ensuring robust safety requirements are met.

Even considering a greater uptake of SCMs, the release of CO₂ from the calcination of limestone during clinker production using conventional techniques means that other technologies, such as CCS, are needed. The NZE Scenario envisages an increase in the capacity of CCS to 170 Mt in 2030.

1 It should be also noted that, in some countries, material substitution occurs during concrete manufacturing rather than in cement production. For such cases, clinker-to-binder ratio might be a more complete metric. However, robust regional data on the clinker-to-binder ratio is currently not available.

Innovative emissions reduction strategies from the past few years include:  

• Following the LEILAC-2 (Low Emissions Intensity Lime and Cement) and Norcem Brevik CCS projects, Heidelberg Materials has announced plans to build a full-scale 1.8 Mt per year (equal to the plant's annual emissions) CCS facility at its Slite plant in Sweden by 2030. 
• Air Liquide (France) was granted EU funding for two CCS projects: the Go4ECOPLANET project aimed at fully decarbonising cement production at a Lafarge plant in Kujawy (Poland), and the K6 Program, which aims to produce the first carbon neutral cement in Europe in Lumbres, France. Together, the two projects, which should start operation between late 2027 and early 2028, are expected to capture 18.1 MtCO₂ emissions over a decade. 
• Brimstone (United States) has announced the development of a new cement-making process that sources lime from calcium silicate rocks instead of limestone. This would avoid the generation of process emissions during calcination and produce a magnesium-based waste product that can even absorb emissions from fuel combustion. The process is in the early stages of development – it is being tested in a small prototype – but plans for a first-of-a-kind demonstration plant in the United States were announced in 2022.
• Promising announcements on electric kilns include VTT Decarbonate reporting on the successful completion of large prototype-scale experiments for its electrically heated rotary kiln in Jyväskylä, Finland. Coolbrook (Finland), Cemex and UltraTech Cement signed memorandums of understanding for the construction of an industrial-scale pilot electric kiln using Coolbrook Roto Dynamic Heater (RDH) technology. 
• Engineers from the University of Cambridge filed a patent for the world's first emissions-free route to recycle Portland cement, with an industrial-scale demonstration expected by 2024. According to the researchers, the process eliminates the emissions from kiln operation, using 80-90% less energy, and reducing total emissions by a least 50%.
  

Carbon capture and storage (CCS) plays a major role in meeting the cement sector emissions reductions required to get on track with the NZE Scenario. Action by governments to deploy supporting infrastructure for CO₂ transport and storage is critical to avoid delays to the implementation of new technologies. It will be important for governments to reform permitting processes to avoid delays and to work with stakeholders to ensure public support for construction of new infrastructure. 

Pipelines are expected to remain the preferred infrastructure for CO₂ transport. Countries with oil and gas infrastructure could investigate the feasibility of repurposing pipelines for CO₂ transport, thus avoiding stranded assets as fossil fuel use declines.

Many states have introduced policies addressing industrial emissions, which are covered in detail under industry tracking. Important developments for cement include:   

• In December 2022, several EU bodies reached a provisional and conditional agreement on the carbon border adjustment mechanism (CBAM), which targets several specific products from carbon-intensive industries, including cement. The CBAM is expected to start operating in October 2023, with a simplified version focused on reporting obligations. It is expected to then be gradually phased in alongside a phasing out of free allocation of EU Emissions Trading System (ETS) allowances to address the risk of carbon leakage. Several countries published roadmaps for the decarbonisation of their cement industry in 2022, including China, whose roadmap was developed by the China Cement Association together with the Rocky Mountain Institute. The expansion of China's ETS, which was expected to include cement, was postponed to 2023. 
• The Cement Association of Canada also published a Roadmap to Net-Zero Carbon Concrete by 2050. The Canadian government updated the minimum price on carbon from C$20 to C$50 per tonne and plans to increase this value at an annual rate of C$15 from 2023 to 2030.
  

Following publication of the 2050 Net Zero Roadmap, GCCA launched a series of Net Zero Accelerator initiatives across four countries (India, Egypt, Thailand and Colombia) representing 10% of global cement and concrete production. The first phase of this initiative will focus on efforts to decarbonise the sector across the global south, a key priority given the increasing demand for cement for infrastructure in developing countries. Phase 2 countries will be announced soon.  

Launched during COP26 in 2021, the Breakthrough Agenda defined a plan to accelerate the decarbonisation of five sectors (power, road transport, steel, hydrogen and agriculture) through a package of 25 collaborative actions to be delivered by COP28 in 2023. The Agenda has been endorsed by 47 countries to date, including G7 and EU countries, India, Egypt, Morocco, Australia, Cambodia and Canada. The Agenda's Industrial Decarbonisation Initiative consists of a coalition of governments and private sector institutions focusing efforts first on steel (in progress), cement and concrete (to be covered by the Cement and Buildings Breakthroughs planned for launch in 2023).

At COP27 in 2022, First Movers Coalition’ members – a group of companies with high purchasing power, pursuing decarbonisation of seven emission-intensive sectors through the creation of early markets for innovative clean technologies – committed to “purchasing at least 10% (by volume) of cement/concrete per year as near-zero cement/concrete inclusive of any SCMs by 2030 and excluding fossil-based SCMs by 2035”. 

Similarly, the Climate Group's Concrete Zero initiative, launched in 2022, brings together leading businesses to create a market for near zero-concrete, with members committing to using 30% low-emission concrete by 2025 and 50% by 2030. The Group defines low-emission concrete as having an embodied carbon intensity below a threshold linked to the concrete specified strength class: for the lowest strength class, concrete is considered low-emission if its embodied carbon sits below 100 kg CO2eq/m³ , while for the strongest class, it must be inferior to 270 kg CO₂eq/m³ . 

In 2021, the GCCA and the World Economic Forum launched Concrete Action for Climate, a coalition of organisations supporting the delivery of net-zero concrete by 2050. The initiative seeks to ensure that both supply and manufacturing are in line with global climate goals, to help design and advocate for appropriate policy levers to stimulate demand for low-carbon cement and concrete, and to incentivise circularity in the sector. 

Other programmes in place to help improve energy efficiency in cement production include the Plant Evaluation Gap Analysis and Support Service (PEGASUS) Programme of the World Cement Association and the GCCA GNR (Getting the Numbers Right) reporting database for use in benchmarking. Others still, such as the GCCA's Innovandi programmes, target innovation.

• Tongbo Sui, Sinoma Internation Engineering Co.Ltd., Reviewer  
• Claude Loréa, Global Cement and Concrete Association (GCCA), Reviewer 
• Rob van der Meer, CEMBUREAU, Reviewer