Laying the foundation for zero-carbon cement

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As a key component of concrete, cement is an integral part of our everyday lives. In fact, it is the second-most-consumed product globally after potable water, and it is used in almost everything we build—from houses and cityscapes to dikes and dams. At the same time, it is also a major contributor to global CO2 emissions.

Scientists and governments alike have called for increasingly stringent greenhouse gas (GHG) emissions targets as the consequences of climate change become more apparent. Recently, the goalpost has shifted from keeping the temperature rise below 2.0 degrees Celsius to 1.5 degrees Celsius, with more than 771 countries committed to net-zero emissions by 2050. Adding to pressures on the industry is the COVID-19 pandemic, which has hit the industry hard, undercutting demand with uncertainty around how deep the downturn will be and how long a recovery will take.

While it’s unclear how the climate debate will unfold, reaching such goals by 2050 will be especially challenging for the cement industry, as most of its COemissions result from the unavoidable chemical process known as calcination. Unlike other industries that may be further along, the development of new technologies to decarbonize cement might not be scalable for years. Nonetheless, our research suggests that, in principle, the industry could reduce its 2017-level emissions by more than three-quarters by 2050.

Given its performance characteristics and the broad availability of limestone, cement (and therefore concrete) is likely to remain the construction material of choice globally. At a local level, however, it could lose share to more sustainable alternative materials, such as cross-laminated timber (CLT). Other shifts, including increased building-information modeling (BIM) and modular construction, could further reduce cement consumption, effectively shrinking demand, despite an overall increase in construction activity. Growth and decarbonization therefore represent significant, interrelated challenges. Paradoxically, perhaps, COVID-19 could accelerate the industry’s response to these fundamental structural trends. As players address the challenges of uncertain demand, they have an opportunity to reset strategies: identifying the best path toward decarbonization, assessing digital and technological advancements to invest in, and rethinking their products, portfolios, partnerships, and construction methodologies—areas we explore later. Forward-thinking players could have an opportunity to leapfrog and become the industry front-runners.

Climate change and the cement industry: A baseline

The cement industry alone is responsible for about a quarter of all industry COemissions, and it also generates the most COemissions per dollar of revenue (Exhibit 1). About two-thirds of those total emissions result from calcination, the chemical reaction that occurs when raw materials such as limestone are exposed to high temperatures.

Cement production is a major source of global CO2 emissions and also generates the most emissions per revenue dollar.

Cement acts as the binder between aggregates (fine and coarse rocks) in the formation of concrete. While cement makes up only a small percentage of the mix (approximately 12 percent by volume), it is almost exclusively responsible for the resulting COemissions. In the cement-manufacturing process, raw materials are heated to high temperatures in a kiln in a fuel-intensive process known as pyroprocessing (Exhibit 2). This results in clinker, small lumps of stony residue that are ground to a powder and combined with other ingredients to produce cement.

Cement manufacturing is a highly complex process.

Pressure for the cement industry to decarbonize has increased rapidly, not only from society but also investors and governments. In fact, governments are now increasingly asking for environmental impact assessments before deciding whether to commit funding. As public scrutiny of COemissions increases, the risk remains that cement players could be “shamed” similar to oil and gas or mining companies in the past.

Potential decarbonization pathways

Companies have several options to decarbonize cement. Optimistically, our analyses show that COemissions could be reduced by 75 percent by 2050 (Exhibit 3). However, only a small portion (around 20 percent) will come from operational advances, while the remainder will need to come from technological innovation and new growth horizons.


Operational advances, such as energy-efficiency measures, have already largely been implemented, and the emissions-reduction potential from alternative fuels and clinker substitution is limited by the decreasing availability of input materials. More innovative approaches, such as new technologies and alternative building materials, will therefore be indispensable to achieve carbon-reduction targets by 2050. That said, the most promising levers, in terms of emissions-reduction potential, are still in development and have only been piloted or implemented on a small scale (see sidebar, “A deep dive into decarbonization levers”).

As the development of technologies such as carbon capture, use, and storage (CCUS) and carbon-cured concrete could take up to ten years, investments should be made as soon as possible. Our abatement cost curve (Exhibit 4) estimates the costs of several large-scale investments to reduce one ton of CO(based on assumed future costs, COprices, and abatement volumes). A negative abatement cost—such as for clinker substitutes—implies a benefit to the producer rather than a reduction in cost.

Decarbonizing cement requires large-scale investments in technologies, bringing down both fuel and process emissions.

Abatement costs indicate ranges, as the exact price of goods depend on regional and future availability. For example, as the steel and energy sectors step up their decarbonization efforts, the availability of clinker substitutes such as pulverized fuel ash (fly ash) and granulated slag will decrease. The same holds true for biomass, which is likely to experience rising demand from other industries.

With the abatement costs of certain levers higher than COprices, cement manufacturers are faced with a dilemma: there is pressure from the public and financial investors to abate quickly, even though there is no economic rationale to do so. Not only do the economics seem far from stellar, but the required investment needs to be directed toward cost-reduction measures for cement producers to maintain their value share in the broader construction industry.

Overall, the future COemissions in 2050 are expected to be in line with global demand, slightly increasing to 2.9 GtCO2 (Exhibit 5). Region-specific differences will persist, and the potential to reduce them will vary across regions because of country-specific regulatory approaches, different consumption needs, and the varying levels at which local industries implement decarbonization measures.

CO2 emissions are expected to decline worldwide compared with the 2050 ‘do nothing’ scenario as traditional and innovation levers can be exploited and further developed.

For instance, China will benefit from a decline in demand (of about 45 percent) and should be expected to deploy both operational advances and technological innovation to decarbonize in the coming decades. Southeast Asia and India have started developing policies to promote decarbonization efforts. In 2012, the Indian government introduced a market-based mechanism to improve energy efficiency in which more than 85 cement plants participate. However, urbanization and economic development in these regions as well as the associated increase in demand may offset these efforts.

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Investor scrutiny and regulatory pressure to reduce carbon emissions in the European and North American markets are likely to intensify. The European Union’s ambitious Green Deal and its exhaustive package of measures, including the introduction of a carbon border–adjustment mechanism for cement, could reduce carbon emissions across the entire region. In North America, decarbonization efforts are promoted through state- and countrywide initiatives, such as Canada’s 2019 implementation of the Carbon Pricing Backstop program.

The next normal: Reimagining the cement industry

Decarbonizing the cement industry requires two strategic challenges to be addressed. First, companies will need to identify the best paths toward decarbonization through operational advances and technological innovation as well as new growth horizons. Second, they will need to develop a portfolio for a new growth horizon that leverages opportunities across the “sustainable construction” value chain.

Operational advances

Building on decades of efforts to improve efficiency, traditional abatement levers could reduce emissions by about one-fifth by 2050. The industry could achieve this reduction by deploying more clinker substitutes, reducing energy intensity through better plant utilization, and increasing equipment effectiveness. Recovering waste heat (a by-product of machines or processes that use energy) could also provide carbon-free electricity.

Another efficiency lever is advanced analytics. One European cement producer achieved 6 percent fuel savings by creating self-learning models of a kiln’s heat profile and optimizing the shape and intensity of the kiln flame. Future cement plants could leapfrog competitors by combining digital technology and more sustainable operations. Finally, incorporating alternative fuels such as waste and biomass to replace fossil fuels, a multi-decade trend in the industry, could reduce emissions by nearly 10 percent by 2050.2

None of this will be easy. Biomass supply varies by region, and other industries are vying for them. Clinker substitutes, too, are limited. Natural pozzolans (for example, volcanic rock and ash) have not yet been assessed at scale. And industrial byproducts that serve as clinker alternatives, such as fly ash from coal-fired power plants and slag from steel-blast furnaces, could be in shorter supply as the power and steel industries decarbonize and produce less waste.

Technological innovation

Innovation will be critical to achieving the cement industry’s sustainability potential, with promising avenues already emerging. For example, one start-up uses a lower proportion of limestone in its cement, which results in fewer process and fuel emissions; this company’s process also locks in additional CO2, which is added before the concrete cures. Adding COmakes the concrete stronger and reduces the amount of cement needed. Carbon-cured concrete could also use COcaptured during cement production. Today’s methods could sequester up to 5 percent of the COproduced during production, but newer technologies could sequester 25 to 30 percent. Products such as carbon-cured concrete, positioned differently, could earn a “green premium,” potentially giving companies an edge among environmentally conscious buyers—and greater pricing power.

On the horizon are CCUS technologies. While frequently costly and perhaps (for now) more suitable for making higher-value products such as steel rather than cement, by 2050, they could more than halve emissions. A number of postcombustion carbon-capture pilots are underway, driven by the large cement players. Other companies are testing oxyfuel combustion, a promising but expensive technology that results in high concentrations of COin flue gas, which in turn allows for near-total carbon capture.

Ultimately, capitalizing on technology and innovation will require more investment, as well as a shift in mindset for companies that have become too comfortable with the status quo. Many cement players are not used to relying on partnerships, or to operating in the kinds of ecosystems that are second nature in other industries. With innovation timelines of five to ten years, these companies could soon find themselves playing catch-up.

New growth horizons

Sustainability ultimately may be the catalyst that pushes the industry to seek growth via new business models, partnerships, and construction approaches. Cement-based concrete will remain the global construction material of choice, but “sustainable construction” value chains are likely to emerge on the regional and local levels, necessitating a reorientation of many corporate portfolios.

In the United Kingdom, for example, recycled material from construction and demolition waste is increasingly being used to replace aggregates in concrete. Cement makers have been slow to seize the opportunity, ceding the waste-recycling business to local construction companies. Meanwhile, in other markets, traditional cement may compete with an improved variety—energetically modified cement (EMC)—which releases less carbon and requires less energy to produce. EMC has already been used (in combination with traditional cement) for a variety of projects in Texas.

Other opportunities lie beyond cement and concrete. Alternative building materials and other approaches will likely play an important role in the decarbonization of the cement industry, though a great deal of uncertainty remains as to how much they will reduce emissions. For example, CLT is already used in a number of markets and has been buoyed by its reputation as a green material. Should roughly 10 percent of cement be replaced with CLT, carbon emissions would be reduced by up to 750 million tons each year (about 2 percent of global emissions).3

Additional new value pools include prefab and modular housing, which incorporate off-site production, and BIM. Greater transparency means less waste and likely a reduction in the amount of cement or concrete required. Indeed, digital technology is at once supporting the cement industry’s decarbonization efforts and contributing to its growth challenges.

Getting started

Companies that hope to lead the industry’s decarbonization efforts must identify the best path forward, pursue the right technological advancements, and rethink their products, portfolios, and partnerships. That said, making decisions on investments in the current asset footprint will remain a challenge. Possible solutions include building an abatement curve, establishing different scenarios, and creating a road map that allows decisions to be triggered based on the outcomes of different scenarios.

A twofold, systematic assessment of decarbonization options can provide transparency on existing levers and accelerate rollout while driving innovations in collaboration with other industries or sectors. This includes plant-specific assessments and creating heat maps and abatement curves as well as the evaluation of local ecosystem partnerships with start-ups, other value-chain players, or governmental institutions.

Climate math: What a 1.5-degree pathway would take

Climate math: What a 1.5-degree pathway would take

To understand the shifts in value pools, cement players should develop a vision of the future target portfolio and business model implications to capture the value of sustainable building solutions. The industry will remain a local business; hence, there remains the need to build this perspective micromarket by micromarket. From there, the findings should be elevated and cross-cutting opportunities, such as sustainable concrete, should be prioritized.

The success of such a strategy, however, depends on leaders’ abilities to achieve an organization-wide mindset change that promotes rethinking the current way of working. Leaders should therefore consider the best ways for encouraging the entire organization in their decarbonization journey.

Cement makers are approaching a moment of truth. Challenges such as decarbonization, ongoing value-chain disruption, and competition against the construction ecosystem’s entire patchwork of players all loom large. With the right mindset, decarbonization and reinvention can go hand in hand: just as automakers increasingly view their role as providing mobility, not just making cars, cement companies could likewise be in the business of providing construction solutions. As climate pressures increase and sales of traditional cement and concrete face threats, the combination of new thinking, innovation, and new business models will be critical to helping ensure a profitable—and greener—future.

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