5. Conclusion and Recommendations
An ambitious vision for decarbonization of cement and concrete is not only a question of scaling up the use of low-carbon materials and putting the sector on a Paris-compatible pathway. It is also about meeting the vision set out in the SDGs: a more flexible, cleaner living environment for the 100 million people who are expected to move to cities over the next 10 years, and for the almost 4 billion people living in cities today.
In the coming years, large quantities of concrete will continue to be used, and transforming how it is made to radically reduce the use of Portland cement is essential. As Section 3.3 explains, low-clinker and novel cements that release far fewer emissions in production are capable of matching the performance of Portland cement. Some already perform better than traditional cement in certain applications.
Today, these alternatives are rarely as cost-effective as Portland cement, and they face constraints in terms of raw material supply, resistance from customers and the difficulty of scaling up industry participation. The challenge is to overcome these barriers via a combination of policy mechanisms, enhanced collaboration, a concerted effort on disseminating best practice and targeted R&D. By creating the conditions for a race to the top, the sector could even become a low-carbon leader.
There is no simple formula or silver bullet. Moreover, while this paper focuses on the many exciting opportunities around clinker substitution and novel cements, greater action is also needed on energy efficiency, sustainable fuels and investments in CCS.
Yet it is entirely feasible that the cement and concrete sector can deliver the rapid decarbonization required to keep the rise in global temperature well below 2°C, and as close as possible to 1.5°C above pre-industrial levels. Current models indicate this can be achieved through incremental steps, and can rely to a significant extent on CCS technology. But other, more disruptive pathways could be accelerated by new business models, advances in material science, digital transformation and a revolution in the wider built environment.
Set for disruption?
Disruptive change in the cement and concrete sector could look quite different to what has been seen in other sectors. In the context of telecommunications or transport, the term ‘disruption’ is usually reserved for transformative changes that radically alter how people think, behave or do business, which often means rethinking from first principles. Such approaches are contrasted with ‘incremental’ or ‘sustaining’ innovations that simply improve existing products and processes.
This understanding of disruption only goes so far in the context of a heavy-industry commodity business such as cement and concrete. The physical importance of construction materials is unlikely to diminish in the same way, for instance, that newspapers have been replaced by news websites. Moreover, a ‘move fast and break things’ approach without safeguards – an approach seen in some sectors, particularly the digital sphere – is far from desirable in the cement and concrete sector, given the importance of maintaining safety and structural performance.
Disruption in the cement and concrete sector will hinge on incremental and transformative solutions alike. On the one hand, smarter approaches are needed to deploy a plethora of already available technologies, while matching solutions to specific locations and the right set of policies to enable such solutions to be scaled up. These individually incremental gains could add up to a step-change in emissions reduction. On the other hand, a much greater push is needed to make tomorrow’s transformative approaches, including the ‘holy grail’ of carbon-negative cements, commercially viable on a wide scale.
The prospect of transformative shifts coming from within the cement and concrete sector should be seen alongside new opportunities – or threats – coming from outside the sector
The prospect of transformative shifts coming from within the cement and concrete sector should be seen alongside new opportunities – or threats – coming from outside the sector. Innovations in connectivity, remote monitoring, predictive analytics, 3D printing and urban design are transforming traditional supply chains within the broader construction sector, with potentially large implications for concrete demand. Some of these technologies may seem to be over the horizon, but it is worth recalling how quickly the power sector changed once providers of renewable energy technologies such as solar and wind shifted from being niche players to disruptive competitors.
As these examples show, digital disruption and advances in manufacturing will play a critical role. Yet disruption in the sector is just as much about enabling people to enhance their skills, make better decisions and collaborate with others.
A global plan for cement sector decarbonization could be rooted in location-specific challenges and opportunities. The availability of a given material, the local climate and soil conditions, access to necessary finance and technology, and material/construction standards all vary across regions and determine the set of options available to cement and concrete producers. Connectivity between regions or cities matters too, not only in terms of infrastructure planning, but also for defining which construction materials can be economically traded.
This is about finding the optimal combination of technology, practice-related and policy solutions for a given location. For instance, while parts of Europe and the US are already feeling the effects of decreasing supplies of traditional clinker substitution materials, such as fly ash and blast furnace slag, China and India are currently producing huge volumes of these. Volcanic rocks and ash will become important in regions such as Italy, Greece and the west coast of North America, where these materials are plentiful.
Several studies suggest that calcined clays present a significant opportunity to increase clinker substitution around the world. These could have particular relevance for emerging and developing countries, especially in locations with existing stockpiles of suitable clays from ceramics industries, notably China and Brazil. Moreover, calcined clays are already being used in reconstruction efforts in Cuba, following damage from Hurricane Irma in 2017. This growing body of experience could lead to the widespread use of alternative materials to accelerate rebuilding after natural disasters.
Trade plays a small but significant and growing role in the availability of clinker substitutes, particularly for countries like Brazil where there is scarcity of key materials. Even within countries, transport is a significant factor. In China, there are underutilized supplies of fly ash in the west of the country, but a scarcity in the east. In Europe, a concentration of well-connected urban areas enhances the viability of concrete recycling.
The availability of construction materials is not just a question of cement and concrete. The viability and sustainability of potential bio-based substitutes for concrete, such as wood and hemp, also depend on local conditions. The environmental benefits could vary significantly, for example, between a well-managed Norwegian forest versus one in a country with weak forest governance.
Major regional infrastructure and connectivity initiatives may shape resource demand for a number of years. China has become a global enabler for infrastructure development through its overseas investments and its growing partnerships with countries involved in its Belt and Road Initiative. Ensuring that mega-initiatives such as these also create the right enabling environment for investment in sustainable infrastructure will require concerted efforts to collaborate and harmonize approaches at the global level.
High-performance building materials will be particularly important for enhancing resilience, including for flood defences and critical-infrastructure protection. Risks to infrastructure and cities posed by extreme weather events are especially serious for those places exposed to flood and hurricane damage, but also where residents need protection from extreme summer temperatures. Traditional concrete can come under strain when exposed to humidity and higher concentrations of atmospheric CO2. While concrete is likely to remain important in applications where the environment is challenging, novel, smarter and more adaptable materials are also needed.
Raising policy ambition
Governments, especially in OECD countries and China, should consider giving a clear market signal by setting a target date for the achievement of net-zero carbon emissions in cement production and/or in the construction sector – recognizing that negative-emissions technologies may need to play a role.
A credible commitment by policymakers to decarbonize the sector could be a major driver of low-carbon innovation. In the past, anticipation of a Copenhagen summit deal and expectations of further tightening of the EU ETS led to a surge in innovative activity in research and in industry efforts such as the Cement Sustainability Initiative. However, patenting activity soon faded in the absence of a strong agreement and the lack of a high carbon price in most markets. Following the 2015 Paris Agreement, there is now a critical opportunity to recreate this momentum and to define a climate-compatible pathway for specific industrial sectors, including cement and concrete.
In many countries, governments are the largest procurers of construction products and services. (In the Netherlands, for example, public procurement has already helped increase demand for low-carbon cement.) Sub-national entities, cities, local authorities and housing corporations have a key role to play in exploring such approaches. A growing number of companies in various countries are also setting carbon-intensity targets for their construction projects. More generally, the major companies committed to 100 per cent renewable energy and electric vehicles could demonstrate further commitment to climate action by requiring the use of low-carbon materials in any buildings or infrastructure they choose to build.
New product standards have long been seen as vital for shifting industry practices and stimulating demand for lower-carbon products, but in the short term these are unlikely to provide sufficient incentive to expand the markets for such products or build sustainable supply chains around them. Current standards, in particular for concrete, hold back the deployment of very-low-clinker cements. Yet it can take decades for a new standard to be approved – and even once this exists, it can take a long time for customers to accept a new type of cement. One recent report suggests that there is little prospect of an overhaul of European cement and concrete standards. In the short to medium term, standards-setting bodies have a key role to play in developing the technologies needed to make more flexible approaches to standard-setting possible, such as accelerated durability testing.
Cement producers can reasonably expect that regulatory frameworks for reducing greenhouse gas emissions will come under greater scrutiny from civil society and governments
The other widely cited policy approach is carbon pricing. Carbon prices could create the necessary incentive to scale up investment in early-stage low-carbon cements, but sufficiently high price levels are unlikely for at least the next few years in key markets such as the EU, China, India and the US. Moreover, carbon prices alone are unlikely to deliver enough investment in new approaches fast enough to generate the deployment rates needed. Evidence from other sectors suggests that breakthroughs can be made through more innovation-led policymaking. One option that has not yet been fully explored is differentiated carbon pricing on the final product, i.e. consumers would be charged for the carbon embedded in the building materials they procure.
Policymakers will need to consider how to encourage a more open approach to data among existing and future market players. This is not straightforward given the vertical integration of the sector today. Several of the opportunities outlined in this report for digital technologies to unlock the potential of low-carbon innovations rely on access to data so that advanced analytics can play a role.
Cement producers can reasonably expect that regulatory frameworks for reducing greenhouse gas emissions will come under greater scrutiny from civil society and governments, and that growing demand for cleaner air will continue to shape public opinion and policy. As confidence grows around the decarbonization of the energy sector and electric vehicles, other industrial sectors may be next in line. Some companies are better placed than others to move fast on decarbonization, or to profit from opportunities to move up the value chain. The launch of the Global Cement and Concrete Association in 2018 appears to represent a potential new coalition of the willing.
Box 4: A multi-track, multi-level approach
Given the different sectors and groups of actors involved, policymakers might want to adopt a multi-track, multi-level approach. In the context of focused deployment support for low- and alternative-clinker cements, this might look like the following:
1. Implementing and scaling up the use of available technologies and practices.
2. Identifying and developing the next generation of technologies.
1. Working with cement producers and academic institutions to:
- Identify and develop alternative binders and novel cements;
- Evolve and improve existing low-clinker binders and alternative binders;
- Identify new sources for clinker substitutes and develop new blends based on these; and
- Market and deploy lower-carbon cements.
2. Working with concrete producers to:
- Disseminate best practice in mixing lower-carbon concretes; and
- Scale up use of carbonation-cured concretes.
3. Working with clients, architects, structural engineers and contractors to:
- Disseminate best practices in working with lower-carbon cement;
- Build demand for lower-carbon cements;
- Scale up material efficiency strategies to optimize the use of building materials; and
- Explore how innovations in the broader built environment will affect upstream sectors.
Sharing experience and knowledge within and across industries, as well as between different regions around the world, should be encouraged and facilitated. International alignment on embodied-carbon targets and measurement for building materials is important as countries increasingly rely on imported materials. Policies directed solely at domestic material producers are unlikely to achieve sufficient reductions in embodied emissions.
The EU can play a powerful role in sharing lessons from its own attempts to shape innovation in heavy industries. Not only are many of the largest cement producers with the greatest R&D capacity headquartered in Europe, but the EU has also been behind some of the most advanced attempts to develop innovation pathways through its ETS. Exchanging knowledge with other countries and regions, such as China, that might hope to promote low-carbon cements through carbon-pricing schemes will be key. Moreover, a shift to using performance-based standards in Europe would be particularly effective, given that European cement and concrete standards are often followed elsewhere.
Cities will play a critical role in delivering these decarbonization strategies, but today they rarely have access to all the necessary policy levers or the capacity for implementation. Cooperation between cities, including on shared lessons on the future of the built environment, will be important. Rapid shifts could be delivered through pilot schemes, smart public procurement, and incentives and regulations encouraging the use of waste materials in cements. Cities can work together to build the market for low-carbon cements through C40-type initiatives – a network of the world’s largest cities committed to addressing climate change – and city pledges.
To be effective and truly disruptive, cooperation will need to bring together new combinations of market actors capturing cross-sector opportunities and addressing cross-cutting challenges in the built environment. Long-term planning can be aided by innovative institutional arrangements to engage a new set of actors at national and regional levels and within different sectors. Existing initiatives, such as the National Infrastructure Commission in the UK, which acts as an independent body, collecting evidence and engaging stakeholders throughout the country, may play an important role in providing a long-term vision for the built environment.
If we are to achieve deep cuts in greenhouse gas emissions in line with the Paris Agreement, there can be no sectoral exceptions. The cement and concrete sector has to change. There are many potential pathways to lower emissions, and not all are likely to succeed. But as this report argues, there are clear approaches that can help create the conditions for the adoption of low-carbon materials and for private-sector leadership. The nature of the necessary interventions will, of course, differ across geographies and national settings.
1. Growing the market for low-carbon building materials
Carbon-neutral or -negative construction will need to become the norm everywhere by around 2030. For this to be achieved, there needs to be a rapid increase in the use of building materials with zero or negative embodied emissions in the next few years.
Many governments in major economies have big plans for investment in infrastructure. Perhaps the most significant is China’s Belt and Road Initiative, which by some estimates will increase demand for cement by 162 million tonnes annually by 2020. Provisional assessments of President Donald Trump’s infrastructure plan for the US suggest it would require approximately 30 million tonnes of cement per year up to 2021. A major road-building initiative in India is projected to require 4 million tonnes per year over a five-year period.
It would be a game-changer if such megaprojects specified the use of lower-carbon cements or alternative products for a large share of their construction. There are many examples of governments already setting ambitious requirements. In the UK, the concrete for London’s Crossrail project must have a minimum cement-replacement content of 50 per cent. Since 2015, the United Arab Emirates has required all major infrastructure projects to use cements that contain at least 60 per cent blast furnace slag or fly ash. Multilateral development banks will have a vital role to play in encouraging or requiring such approaches in the projects they help finance.
Yet while major infrastructure projects are well suited to the introduction of novel products, another test is whether governments start to commit to ambitious sustainability targets for social housing or even all new buildings, which would likely trigger profound changes in market structure.
The ultimate goal here should be material and technology neutrality at the building or city scale. This would guide consumers to choose not only more sustainable solutions but also the most appropriate option for any given project, while allowing suppliers to innovate to meet those demands. Policies and regulations should encourage a shift towards functional or performance-based specifications, rather than prescribing or forbidding the use of a particular material.
In the meantime, targets for embodied carbon in construction materials could be introduced with little risk of carbon leakage, helping to align incentives and responsibility for net-zero-emissions construction along the value chain. This matters because concrete often accounts for a small share of the total cost of construction projects, and the end-users in construction may be better able to absorb the costs of mitigation.
- Mainstream embodied carbon. An international standards committee should convene expert stakeholders, construction firms, architects and structural engineers to establish an industry-wide methodology for measuring embodied carbon, as well as a process for gathering and sharing data on buildings and materials. This methodology would need to be granular enough to capture supply-chain-specific aspects. Governments should mandate the measurement of embodied carbon across projects. They should provide information sources, training and support for contractors and engineers who might be asked to carry out these assessments. Metrics on embodied carbon should be integrated into sustainability-rating codes.
- Introduce CO2 footprint labelling for construction materials. Material suppliers should establish labelling schemes indicating their carbon credentials. The introduction of reliable and certified CO2-footprint marking of materials (down to zero CO2 emissions per tonne) would help to make it attractive for users to pay a premium for CO2-neutral building materials. Policymakers should also explore setting a maximum threshold for the embodied carbon allowed in the construction of low-risk, non-structural applications such as house slabs and non-load partition walls.
- Promote a whole-life-cycle approach to low-carbon public procurement. Governments should restructure the typical tender route for building materials on large public projects so that it integrates embodied-carbon measures and end-of-first-life considerations in addition to the operational phase emissions usually considered, with bidders required to calculate the embodied carbon of the materials they are supplying. Governments could set maximum embodied-carbon levels in public tenders, specify minimum cement-replacement levels for large infrastructure projects, or implement scoring systems that strongly favour low-carbon proposals. Public agencies and companies should seek to specify a service rather than a product, encouraging a shift towards less resource-intensive business models. Policymakers should also work with insurers to ensure that clients who specify novel materials are not constrained by unnecessarily high insurance rates.
- Secure commitments from major concrete-consuming companies. Firms with significant influence over construction decisions or with major capital investments in construction should set ambitious carbon-intensity targets for major projects and engage with construction companies, design teams, contractors and material suppliers to encourage them to find the lowest-carbon, most viable options for a given project. Construction companies and material suppliers should collaborate on training to encourage design teams and contractors to familiarize themselves with novel materials, so that designers/contractors can in turn recommend them to clients or specify them when ordering from material suppliers.
2. Building the supply chain for net-zero emissions materials
As demand for low-carbon materials is ramped up, a host of changes will be needed in material supply chains. Governments will need to find ways to incentivize investment in distribution networks for clinker substitutes, and in the additional processing equipment and storage infrastructure that may be required to scale up the provision of lower-carbon cements. Incentives to use clinker substitutes and novel cements will need to be accompanied by best-practice dissemination and support to make the use of innovative products viable. The use of waste materials and other cement additives, for instance, requires specialist knowledge and equipment that are often lacking in emerging markets.
- Build capacity and diffuse best practice in emerging markets. Developed countries should establish partnerships with emerging markets to facilitate knowledge-sharing between material-research labs and construction and engineering companies to encourage best practice on low-clinker and novel cement, and around more efficient cement use more broadly. Such partnerships could also enhance access to the equipment and chemical admixtures needed to optimize concrete design; dedicated specialists could be deployed to key plants in regional clusters, as well as to smaller mixing and batching plants in each area.
- Gather data on material availability in different regions. Major importing countries could work with large suppliers to improve data on the availability of clinker substitutes, such as fly ash and blast furnace slag, in different regions. This could be done as part of the Cement Sustainability Initiative’s Getting the Numbers Right database and would enhance stakeholders’ ability to track the availability of materials in different regions over time, providing insight into the possibility of importing from different locations and visibility of when shortages are likely to occur and where.
- Improve incentives to recover and process waste materials and use them in cement and concrete. National and local governments could use tools such as landfill taxes and other restrictions to encourage coal and steel companies to (a) find markets for their waste products and (b) invest in equipment for collecting, processing and storing their waste products.
- Encourage the reprocessing of waste from old disposal sites. Regulations for the storage and disposal of secondary materials could include incentives to screen, test and process materials from ash fields, slag stocks and bauxite waste to increase supplies in the short term, while also addressing significant environmental challenges. These supplies can be huge in scale, but their quality is variable and they are not always located conveniently relative to cement and concrete production sites.
- Optimize the efficiency of cement use in concrete. Cement producers will need to invest in additional equipment to use alternative clinkers and scale up the use of clinker substitutes. This includes pre-processing equipment such as specialized grinding machinery and calciners, as well as additional silos.
3. Expanding the portfolio of low-carbon cements
Technologies take a long time to get from laboratory to market in many sectors, but low-carbon cements seem to face particular challenges in bridging this ‘valley of death’. A considerable push is required to get the next generation of low-carbon cements out of the lab and into the market.
Given the huge scale of cement production, it is not sustainable to provide long-term subsidies for low-carbon alternatives. Instead, the goal should be to identify a suite of materials, technologies and approaches that have the potential to rapidly become more cost-effective once deployed at scale, and to focus support for innovation in these areas.
Not all novel approaches will succeed, but those that do may well have significant decarbonization potential. As well as additional funding for R&D and demonstration, new models of cooperation around innovation between companies and across borders will be important.
- Develop demonstration projects. Large-scale demonstration projects are needed to build confidence in novel products and engage stakeholders along the supply chain. Initiatives should involve a broad group of universities, construction companies, engineering firms, regulatory authorities, asset owners and industry stakeholders. As part of these efforts, novel financing mechanisms could be explored, such as investing in accelerators or incubators to stimulate innovation capacity within the sector and enhance private financial participation in R&D projects.
- Expand R&D capacity in the sector. Industry stakeholders, governments and research funds such as the EU’s Horizon 2020 should focus efforts on basic materials such as cement and concrete. In particular, belite ye’elimite-ferrite (BYF) clinkers, carbonatable calcium silicate clinkers (CCSC) and magnesium-based cements require further research support. Engineering courses should include novel cements and low-carbon considerations in their syllabuses.
- Explore new models for cooperative innovation. Governments should create new avenues for cooperation both among cement producers and along supply chains to promote the development and diffusion of novel products. The current reluctance of cement producers to collaborate is born out of previous experiences with antitrust legislation and uncertainty over the application of competition law. Governments, cement producers and actors in the broader supply chain should work together to identify ‘pre-competitive areas’ – in which companies work together to tackle systemic issues, and in which collaboration could be encouraged through, for example, stakeholder advice platforms. At the more ambitious end of the scale, governments could consider creating patent pools or cross-licensing schemes to encourage innovation and mass diffusion of relevant novel-cement technologies.
- Support and expand joint R&D at the international level. Governments and research funds should support and enhance capacity for joint R&D on lower-carbon cements at the international level, including by expanding Mission Innovation – a commitment to invest in R&D for energy – to have a remit for low-carbon construction materials. National standards institutes should collaborate on testing facilities. Universities could lead work to establish accelerated laboratory endurance tests to validate new materials and bring these options to scale.
- Build diagnostic tools. Material-science laboratories should work with technology and construction companies to develop effective diagnostic tools and field-based detection tools for assessing the strength and durability of concrete. Policymakers, insurers and local authorities should stipulate the use of in situ testing, data collection and data dissemination for major projects using novel products.
4. Harnessing digital disruption
The digital revolution will not remove all the physical and economic challenges of decarbonizing cement and concrete, but it can make a dramatic difference – whether via optimizing supply chains, enhancing collaboration, or providing workers in all relevant fields with the data needed to make economically viable and technically appropriate decisions on low-carbon materials. Digital tools, for instance, will play a key role in building the market for novel cement and concrete products by addressing misinformation, enhancing collaboration, disseminating best practice and reducing asymmetries in access to relevant information at different points along the value chain. These tools are especially important for growth markets such as China, India and countries in sub-Saharan Africa.
Industrial sectors also offer some of the most promising near-term opportunities for using machine learning to increase profit margins and reduce emissions. Today, the application of AI in industrial and commercial applications is primarily focused on optimizing logistical operations in the high-tech, relatively controlled environment of industrial plants, or on identifying promising new materials. But many of the recommendations in this report depend on decisions being made based on factors ranging from material availability to expectations of material performance in specific contexts. Machine learning is well suited to this challenge. Where it is not yet capable of producing fully fledged autonomous decisions, it could still have powerful applications in the sector: for instance, by providing a clear set of decisions for workers to select from, drawing on a wealth of historical and real-time data.
- Design digital tools for disseminating best practice. Material-science labs, cement companies and engineering firms should work with leading technology firms and internet platform providers to design open-source, user-friendly and affordable digital tools to disseminate best-practice guidelines on how to optimize concrete mixes for locally available materials and given applications.
- Develop platforms for coordination along the value chain. Enhancements to existing digital tools, such as BIM, could help ensure the integration and engagement of all key players along material and construction supply chains. However, this depends heavily on the use of appropriate and effective mechanisms for data sharing.
- Safeguard beneficial applications of AI in industrial sectors. A major push is needed by industry stakeholders and technology pioneers to explore the beneficial uses of machine learning and wider AI in terms of meeting the challenge of deep decarbonization in industrial sectors. Such an initiative could be convened by the Partnership on AI – a technology industry consortium focused on establishing best practices for AI systems – including leading firms in cement and concrete, steel, chemicals and other heavy industries.
- Support open and inclusive innovation. Governments should work with universities to host open innovation platforms for exploring the potential for digital technologies to transform processes in the built environment. Innovation partners should work together to build the stack of digital assets needed to integrate real-time decision tools, supply chain optimization and lesson-sharing from experience into the development of new materials and blends. Governments should also provide training to address the digital-skills shortage in the construction sector and cement and concrete sector, also with a view to retaining the number and improving the quality of jobs in each sector.
Establish a vision for a digital future. Cement companies should assess their readiness for disruptive trends more systematically and with a wider range of stakeholders. The Cement Sustainability Initiative or the Global Cement and Concrete Association could convene a group of cement companies, construction companies and technology providers to take part in scenario analyses, to test the assumptions used in current modelling exercises and to map out a digital future for the sector.
5. Developing partnerships for climate-compatible pathways
Several of the solutions proposed above depend on well-coordinated international efforts, whether on research, best-practice dissemination or procurement. The cement and concrete sector encompasses multiple types of actor, different country contexts and different private-sector interests. Coordinating these and orienting them towards a net-zero-emissions pathway will be key.
- Set sectoral targets. Governments should set sectoral targets, including for cement, in their mid-century, low-carbon development strategies for meeting commitments under the UN Framework Convention on Climate Change (UNFCCC), and should include heavy-industry sectors in their Nationally Determined Contributions. Canada’s mid-century strategy, for example, projects a 93 per cent reduction (on 2015 levels) in emissions from cement and lime by 2050.
- Secure G20 commitments. At the international level, a taskforce should be established under the G20 to agree on international commitments for a net-zero-carbon, resilient built environment. This should be linked with the Global Infrastructure Connectivity Alliance, the G20’s work around energy and climate change, and the Financial Stability Board’s taskforce on climate-related financial disclosures.
- Set science-based targets. Major cement and construction companies should set science-based targets (SBTs) as soon as possible and work together to achieve them. These should be ‘feasible by design’ in that they factor in what is commercially viable and technically realistic, but must also be in line with the Paris Agreement. Setting these targets would signal companies’ commitment to addressing climate risk to investors, policymakers, customers and employees. SBTs will not be a perfect representation of reality, but they utilize a set of tools and methods that could be used by firms to rally support for practical but ambitious emissions reduction goals, which could then be rolled out throughout the firms in question, and in partnership with suppliers and customers.
- Facilitate leadership from pioneer cities. Cities should work together to build the market for low-carbon cements and construction products by aligning their goals via the C40, ICLEI-Local Governments for Sustainability and Urban Leadership Council. This could include collective city pledges and developing common principles for what a low-carbon, clean-air and climate-resilient city should look like, as well as agreeing guidelines and flexible standards to inform decisions along the supply chain from planning, design and construction through to operations and end-of-first-life.
- Mobilize a coalition for a circular built environment. This coalition would bring together policymakers, academics and industry stakeholders to test the viability of circular approaches along the construction value chain – from material efficiency in design to better use of secondary materials – and explore policy measures to promote these. It would provide a platform for interdisciplinary research on the role of buildings in a circular economy and vice versa, and explore in greater detail the links between the fast-evolving technological trends and societal challenges explored in Chapter 4. Building on the work of existing initiatives, such as the Buildings as Material Banks project focused on construction and demolition waste, it would work to bridge knowledge gaps in this area, demonstrate the business case for circular approaches and raise awareness among built-environment stakeholders.
- Scale up finance for a sustainable built environment. Governments and multilateral development banks involved in large multilateral infrastructure projects, such as those associated with China’s Belt and Road Initiative, should establish a set of sustainability criteria for projects and structures, including targets for maximum embodied-carbon content and the operational carbon of the structures involved.