ICR looks at the impact of various methods such as use of alternative fuel and raw materials, tackling the emissions issue and encouraging carbon capture in a bid to make green cement and progress towards Net Zero goals.
The analytical journey is long past its prime when it comes to diagnosing the emission problem pertaining to cement and concrete. There is no denying the fact that the problem is too big. If concrete was a country, it would be the biggest production centre as all other commodities put together will not even come close to the 30 billion tonnes of concrete that the world produces every year. If cement was a country, it would be the third highest emitter of CO2 in the world. But the efforts have been to find an approach that would force corporations to either limit and progressively reduce over time the impact on the environment through a slew of measures directed at reducing the carbon footprint of cement. The chart attached shows the distribution of the CO2 emission based on the processing steps for making cement from limestone.
United efforts The last five years has seen acceleration in the efforts towards finding significant pathways for reducing carbon footprint in cement production around the world. The progress on substantial reduction has been positive with concentration in the following areas:
Focus on Calcination Emission: Reducing clinkering by adding alternative materials that can replace clinker
Focus on Fossil Fuel Emission: Efficiency improvement in a number of areas that reduce the use of fossil fuels per unit of cement output, together with the use of alternative fuel. Under the first category, we see a rise in the use of fly ash from the coal-based power plants that replace clinker during grinding and the percentage increase in the last five years on this count would be around 2 per cent (31 per cent moving to 33 per cent with the balance being clinker). Alternatively, the use of blast furnace slag has seen a rise of 5 per cent (50 per cent moving to 55 per cent with the balance being clinker). Both of these actions have taken the total CO2 emission to 860 kg per tonne for some of the best operating plants of the world. The challenges for the future in this regard is that fly ash will remain a constantly depleting resource as all fresh investments into coal fired power plants are scrutinised and it is most likely that the current generation of fly ash will not move up in the coming years. This poses some challenges for the future as the emission pathways that consider use of fly ash as a potential lever for replacing clinker would have to find new pathways as a countermeasure. The use of blast furnace slag also has the same problem brewing at large as steel production is slated for overall sustainability improvement measures, which ordains reduced output of blast furnace slag as a definitive measure.
Tackling the emissions issue This leaves the focus on alternative use of other non-fossil fuels for producing cement, where the actual progress is almost entirely hinged on renewable sources producing electricity that would be used for clinkerisation as well as for grinding. While the latter has progressed well, the former is still at a stage where a handful of cement units have signed up for the alternative technology in kilns. Most of the technologies so far have progressed little towards solving the real issue of emission stemming from the clinkerisation process itself, as the molecular structure change from limestone to clinker involves generation of CO2 quite inevitably. The solutions therefore looked at ways of capturing carbon from the emission process, somewhat similar to the photo-synthesis process in plants as Professor Dr Aldo Seinfeld from ETH Zürich has shown. However, the progress is still at a laboratory scale and to find an economic solution will still take some time. For example, most cement kilns today produce close to 2.5 million tonnes of clinker and the sizing is only moving up, which means the amount of CO2 generation from these kilns per year would be close to 2 million tonnes. To get CO2 capturing systems to scale up to these levels would need many years.
Putting carbon to good use The question is how can we help to scale up the capacity to sequester and store carbon from the emissions from cement kilns? The problem needs to be approached scientifically to make the process economical, which is where the current focus is. But more than the laboratories where this progress is well grounded, we need the cement corporations to set aside funds for investments that need to be made for all future kilns that have the provisions for carbon capture. The next question is to look at how the stored carbon can be put to use in production of concrete? This requires more than the usual scientific research, as the supply chain of concrete making must factor in ways and means of finding pathways for using stored carbon in the concrete making. The Economist reports that companies like CarbonCure, a Canadian firm, are doing this. They have fitted equipment, which injects CO2 into ready-mixed concrete to more than 400 plants around the world. Its system has been used to construct buildings that include a new campus in Arlington, Virginia, for Amazon, an online retailer (and also a shareholder in CarbonCure), and an assembly plant for electric vehicles, for General Motors in Spring Hill, Tennessee.
Piloting new technologies One of the other areas of focus has been to find an alternative route to clinkerisation that is based on electricity. Calix, based in Sydney, Australia, is working on an electrically powered system, which heats the limestone indirectly, from the outside of the kiln rather than the inside. That enables pure CO2 to be captured without having to clean up combustion gases from fuel burnt inside the kiln—so, if the electricity itself came from green sources, the resulting cement would be completely green. A pilot plant using this technology has run successfully as part of a European Union research project on a site in Belgium operated by Heidelberg Cement, a German firm that is one of the world’s biggest cement-makers. A larger demonstration plant is due to open in 2023, in Hanover, to help scale up the technology. Almost all of this would need sacrifice from many stakeholders, as the cost of making cement and concrete will rise as investments have to be made in new technology. Bill Gates’ book, ‘How to Avoid a Climate Disaster,’ projected an increase of the cement making cost from the current $125 per tonne to a range of $219 to $300 if the CO2 emissions have to be taken care of for achieving Net Zero. However, the price of cement is already much above $125 per tonne even without factoring any of the carbon capture and sequestration measures, so the real rise could be much more. A community of stakeholders, starting with the corporation making cement, the community near the cement kilns, the customers, the suppliers and the government, all have a role to play to find a solution how this increase in costs would have to be borne and distributed. Carbon taxes have always been the time-tested path to decarbonisation. Stringent use of taxes as a potent tool has seen better progress, especially in Europe, where some serious progress has happened. Recycling of cement from the demolition waste is one great example. The best example of coordination and collaboration is captured in the initiatives of the world’s largest kiln near Wuhan, where one would witness how the city municipality came forward to proactively recycle the entire city municipal waste into the kiln of the cement unit situated on the Yangtze river. The waste is transported by barges and through a pipeline taken directly into the cement kiln. Such collaboration could replace the hard stand of putting penalties, which after all could be regressive at times.
Indian Cement Review (ICR) and Fuller Technologies brought industry, policy and technology leaders together to discuss how cement innovation can drive green construction at scale, writes Rakesh Rao.
India is building at a pace few countries can match. Highways, airports, housing, logistics parks, industrial corridors and urban infrastructure are reshaping the country’s economic geography. But beneath this growth story lies a difficult question: can India continue to build at scale without locking itself into a high-carbon future?
That question formed the core of an online panel discussion titled “Driving Green Construction Through Cement Innovation”, organised by Indian Cement Review (ICR) in association with Fuller Technologies as the Presenting Partner on June 25, 2026. The webinar brought together experts from cement technology, R&D, global industry platforms, building performance policy and international development cooperation to examine how low-carbon cement and material innovation can accelerate India’s green construction transition.
The discussion came at a crucial time. India has committed to achieving net-zero emissions by 2070 and reducing the carbon intensity of its economy by 45 per cent by 2030. At the same time, the country’s construction sector is expanding rapidly, driven by urbanisation, infrastructure development, housing demand and industrial growth. Cement, as one of the most widely used construction materials, sits at the heart of this transition. It is indispensable to development, but also central to the challenge of reducing embodied carbon in buildings and infrastructure.
Moderated by Nitika Krishan, Senior Urban Infrastructure and Sustainable Policy Consultant, the panel featured:
Dr Hemantkumar Aiyer, VP and Head R&D, Nuvoco Vistas Corp Ltd;
Devika Wattal, Innovation Lead, Global Cement and Concrete Association (GCCA);
Dr Sunita Purushottam, MD, GBPN India (Global Buildings Performance Network); and
Vaibhav Rathi, Senior Technical Advisor, GIZ (the German Agency for International Cooperation)
Setting the tone for the discussion, Nitika Krishan underlined the scale of the challenge before the sector. “The question before us is no longer whether we build, but how we build sustainably,” she said. She pointed out that construction accounts for nearly 40 per cent of global energy-related carbon emissions when both operational and embodied carbon are considered. Cement production, she added, remains one of the hardest industrial processes to decarbonise.
For India, this is not merely an environmental issue. It is a development issue, a competitiveness issue and increasingly, a market issue. As one of the world’s largest cement producers and among the fastest-growing construction markets, India’s material choices will influence the carbon trajectory of its built environment for decades. As Krishan observed, sustainability solutions in economies such as India must not remain limited to laboratory success. They must be scalable, commercially viable and practical at national level.
The innovation gap: From technology to market
Experts believe that there is a need to bridge the innovation gaps for making decarbonisation in cement and concrete scalable. Devika Wattal of GCCA, explained, “The starting point must be the core cement manufacturing process itself. The first and foremost is the heart of our process, the heart of cement manufacturing. How do we reduce clinker? That is always a topic where industry is working very intrinsically.”
Clinker reduction remains one of the most important pathways for lowering emissions in cement. Since clinker production is energy-intensive and chemically emits carbon dioxide, reducing the clinker factor through supplementary cementitious materials (SCMs), blended cements and new chemistries can have a significant impact. Wattal also noted that carbon capture, utilisation and storage (CCUS) will have a role, though it may not be the first lever for all markets.
However, she stressed that innovation cannot stop at technology development. A solution that works in the lab must also be adaptable to industry, scalable in production and acceptable in construction practice. “It is important for that innovation to be adaptable, to be scalable, and so that it can be executed in real time,” she said.
Wattal also called for stronger enabling systems around innovation. These include performance-based standards, product-level embodied carbon databases and clearer frameworks for evaluating green materials. Without these, low-carbon cement products may struggle to compete with conventional materials in procurement and design.
R&D must balance carbon, cost and performance
Bringing in the R&D perspective into the discussion, Dr Hemantkumar Aiyer of Nuvoco Vistas emphasised that low-carbon cement development cannot be treated as a single-variable exercise. Cement must perform in real construction conditions. It must deliver strength, durability, consistency and cost competitiveness, while also reducing carbon.
“The root of understanding and balancing all these aspects lies in materials, and knowing the materials,” he said.
According to Dr Aiyer, R&D teams must understand the variability of raw materials such as fly ash, slag and clinker. Different sources produce different material behaviours. This makes mix optimisation, material characterisation and processing-property relationships critical. When performance is affected, cement manufacturers must understand how strength enhancers, admixtures and other performance chemicals interact with the material system.
He also linked material science with process efficiency. Clinkerisation takes place at extremely high temperatures, around 1,400 to 1,450 degrees Celsius. Any improvement in raw mix design, process control or energy optimisation can, therefore, help reduce emissions and cost. Dr Aiyer pointed to artificial intelligence-based optimisation, Cement 4.0 tools and advanced software as important enablers for real-time process and material control.
“The more you understand the materials, the more you can control it,” he said.
LC3: The promise is proven, the sequencing is not
Limestone calcined clay cement, commonly referred to as LC3, has attracted global attention because it can reduce clinker content significantly by using calcined clay and limestone while maintaining performance in many applications. Kiranmai Sanagavarapu of Fuller Technologies said the technology itself has already moved beyond proof of concept. Fuller Technologies has worked with calcined clay technology for nearly two decades and has seen plants running in France and Ghana. These plants, she said, are meeting local and national specifications, while the economics are beginning to make sense.
“The calciner is performing, the economics is stacking up, it is making business sense to produce,” she said.
But if the technology is viable, why has adoption not scaled faster? For Sanagavarapu, the answer lies in project sequencing. Too often, clay characterisation happens after equipment is specified. This, she warned, is a backward approach because calciner design depends on clay mineralogy, kaolinite content, iron levels, reactivity, moisture and other variables.
“If you don’t know what your deposit looks like before you commit for the equipment, you are, in a way, going blind into designing,” she said.
She also identified permitting and plant integration as major bottlenecks. Environmental clearances, mining permissions and local regulatory approvals must begin early. Similarly, calcined clay must be integrated into existing grinding, blending and logistics systems from the design stage, not treated as an afterthought during commissioning.
India already has IS 18189:2023 standard for LC3, but Sanagavarapu pointed out that the standard is not yet visible enough in procurement documents. “The gap between what is technically being permitted and what the procurement is asking is the single biggest bottleneck,” she said.
In her view, successful scale-up depends on getting the sequence right: clay characterisation first, permitting in parallel, standards aligned with construction, and integration built into plant design.
India’s LC3 journey: Progress, but demand remains thin
Providing details of India’s LC3 commercialisation experience, Vaibhav Rathi of GIZ noted that JK Cement carried out the first commercial production of LC3 at its Rajasthan plant, followed by JK Lakshmi Cement three months later. These initiatives were supported by the International Climate Initiative of the Government of Germany, with IIT Delhi contributing deep institutional knowledge on LC3 research and BIS certification.
Rathi said India’s early experience has produced clear lessons. One of the biggest was the need to build capacity among regulators. While BIS certification existed, State Pollution Control Boards were unfamiliar with the technology and unsure about the approval pathway.
“The capacity building is not just needed amongst the producer and the users of the cement, but also the regulators who are working with this technology for the first time,” he said.
He also highlighted the need for better information on China clay deposits. Since China clay is currently classified as a minor mineral, centralised data on availability, quality and location is limited. If cement manufacturers are to adopt LC3 at scale, stronger mineral intelligence will be important.
The third issue is demand. LC3 has already been used in projects such as Palava City in Mumbai and Noida International Airport, but these remain limited examples. “It is in a chicken and egg situation,” Rathi said. “Cement companies are saying we need more demand, and users are saying there is not enough cement available.”
Public procurement, he suggested, could help break this cycle. If agencies such as CPWD and other public bodies begin testing, accepting and specifying LC3, it could create the market confidence needed for cement companies to invest in production and storage.
Building codes must catch up with innovation
Dr Sunita Purushottam of GBPN India argued that material choices will determine built environment emissions over the long term, but India’s current policy signals remain fragmented. Although LC3 has received BIS recognition, she pointed out that building codes, municipal bylaws, schedules of rates and sustainability codes do not yet provide uniform guidance on low-carbon cement.
“The current cement regulations are largely prescriptive and favouring traditional materials,” she said. This limits the ability of alternative materials to compete on performance, durability and emissions.
Dr Purushottam also raised the issue of taxation. Cement, including LC3, currently falls under the same GST bracket as conventional cement. A differentiated tax structure, she argued, could help accelerate market adoption. “In order for the market to demand LC3, that differentiation in the GST could go a long way,” she said.
She noted that green building certifications such as IGBC and GRIHA are already creating demand for low-carbon materials by assigning points for embodied carbon and sustainable material use. However, she said large-scale adoption will require regulatory mandates, particularly through building codes and state-level notifications.
She also cautioned that low-carbon cement alone does not solve the entire building performance problem. A material may reduce embodied carbon, but the operational carbon of a building depends on thermal performance, design, insulation and energy use. “The energy part has two elements,” she said. “One is the embodied carbon of the material itself, and the other is the operational carbon.”
Collaboration is the bridge between invention and impact
Wattal said GCCA sees innovation as a strategic priority and works through platforms that connect industry with academia and start-ups. “There is no way we will decarbonise our sector without innovation,” she said.
However, she stressed that research must be connected to actual industry challenges. Innovations developed in isolation may fail when they encounter real-world barriers such as raw material variability, plant integration, cost, standards and finance. Start-ups, too, need industry mentorship and scale-up pathways.
Wattal also flagged the importance of finance. Even strong technologies may struggle to attract investment if there is no common understanding of bankability. “We have always put projects into, is this a bankable project? But the definition of a bankable project has never been defined,” she said.
For India, she saw strong potential in its academic and start-up ecosystem, but said the challenge lies in alignment and prioritisation. The country has the research base, industrial capacity and market size. What it now needs is a coordinated route from innovation to deployment.
There is a practical concern for cement manufacturers: how can existing plants be adapted for lower emissions without compromising reliability or commercial viability?
Kiranmai Sanagavarapu addressed, “The reliability risk in calcined clay retrofit is definitely real, but it is almost always self-inflicted. The risk arises when a new process is added to an existing circuit without properly redesigning grinding and blending configurations.”
Existing cement plants, she explained, can take two broad routes. The first is external sourcing of calcined clay combined with mill optimisation. This requires lower capital investment and can potentially move in 12 to 18 months if other conditions are in place. It may reduce emissions by around 20 to 30 per cent. The second route is integrated calcination on site, which requires higher capital expenditure and longer lead times, but provides greater control over quality, supply and emissions reduction potential.
For Sanagavarapu, the principle is simple: low-carbon retrofits must be designed with intent. “Design it with an intent properly from the start. Start in the market conditions where the economics are already working,” she said.
Circularity: The overlooked advantage
According to Vaibhav Rathi, fly ash and slag are already well established in cement and construction (C&D), but construction and demolition waste remains underutilised. “C&D waste is a growing business opportunity which not many have taken up,” he said. India’s continuous construction and demolition activity creates huge volumes of waste, much of which contributes to air pollution, land degradation and material inefficiency. With the right processing and standards, this waste can be converted into useful construction products.
Rathi also pointed out that LC3 has a circular economy dimension that is often overlooked. It can use low-grade kaolin-rich clay left behind after high-grade clay is extracted for other applications. “LC3 is not only a low-carbon solution, but also a circular economy solution,” he said.
At the same time, he cautioned that LC3 in India is not yet cheap because it has not reached scale. Site-specific techno-commercial feasibility studies, supported jointly by development agencies and industry, could help companies assess whether LC3 production makes technical and financial sense at a given location.
Dr Purushottam added that India must address both low-carbon cement and construction waste together. “Both low-carbon cement and C&D waste go hand in hand. India does not have an option but to work on both,” she said.
Dr Aiyer called for policy shifts from both government and industry, including preferential purchasing of sustainable materials, minimum supplementary cementitious material requirements in public and public-private projects, and faster regulatory implementation. “If we can fast-track the regulatory standards and their implementation on the ground, that is the way to go,” he said.
From green ambition to green construction
Cement innovation is no longer only about chemistry. It is about systems. Low-carbon cement will scale only when technology, standards, procurement, finance, regulation, education and construction practice move together.
LC3 and other low-carbon technologies have shown promise. India has early commercial examples, strong research capability and growing market interest. But mainstream adoption will depend on whether demand can be created, regulators can be capacitated, standards can be embedded in procurement, and manufacturers can see a clear business case.
For a country building at India’s scale, the opportunity is enormous. Cement will continue to be central to infrastructure and urban development. The challenge now is to ensure that the cement used in India’s growth story carries a lower carbon burden.
Rakesh Rao
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JK Cement gained after being declared preferred bidder for the Gilund Limestone Block in Chittorgarh, Rajasthan, a lease area of 370.96 hectares. The firm saw its shares trade at Rs. 5550.05, up by 28.45 points or 0.52 per cent from the previous close of Rs. 5521.60 on the BSE. The scrip opened at Rs. 5569.15 and touched a high of Rs. 5625.00 and a low of Rs. 5531.00.
The stock recorded turnover of 1742 shares on the counter and the BSE group A stock with face value Rs. 10 has a 52 week high of Rs. 7565.00 on 20-Aug-2025 and a 52 week low of Rs. 4670.05 on 12-Jun-2026. Last one week high and low stood at Rs. 5625.00 and Rs. 5329.00 respectively. The promoters holding in the company stood at 45.66 per cent, while institutions and non-institutions held 40.61 per cent and 13.73 per cent respectively.
The e-auction conducted by the Government of Rajasthan resulted in the company being declared preferred bidder for the mining lease, and the allocation will enable the company to plan phased development of the deposit, subject to regulatory approvals. The Gilund block spans 370.96 hectares and its allocation is intended to support raw material security for the company’s cement operations in the region. The designation follows the government auction process and will allow the company to plan development and integration of the deposit into its supply chain.
The current market capitalisation stands at Rs. 430.38 billion (bn), reflecting market response to the mining news and prevailing valuation levels for the sector. Investors and analysts will watch for formal allotment and related disclosures that can clarify timelines, capital expenditure and expected production profiles. The report is intended for informational purposes and does not constitute investment advice, and market participants are advised to consult advisers before making decisions.
Star Cement has been declared the preferred bidder for the mining lease for Boro Lakhindong West Block following e-auctions conducted by the Government of Assam. The block is located in Boro Lakhindong Village, Umrangso Tehsil, Dima Hasao District, Assam, and extends over an area of 123 hectares. The estimated limestone resource is 207.822 million (mn) tonnes (t), a quantity that will supply raw material for cement production and support the company’s manufacturing operations in the region.
The company is engaged in the manufacturing and selling of cement clinker and cement and distributes products across the north-eastern and eastern states of India. Star Cement operates plants and logistics networks that procure and process limestone to produce clinker for cement, and the addition of Boro Lakhindong is presented as a strategic enhancement of feedstock availability. The preferred bidder status secures rights to the specified lease area under the terms of the auction process.
Financial results for the company in the fourth quarter of fiscal year 2026 showed a consolidated net profit rise of 20.24 per cent to Rs 1,481.0 mn on an 11.54 per cent increase in revenue to Rs 11,735.5 mn compared with the corresponding quarter of the previous year. Those results reflected higher sales volumes and revenue growth in the company’s primary markets and are cited in company disclosures accompanying the lease announcement. The reported performance provides context to the company’s ability to pursue and finance new mining lease opportunities.
Market reaction to the declaration was modest, with the scrip rising zero point thirty six per cent to trade at Rs 212 on the BSE. The award of the Boro Lakhindong lease concludes the e-auction process for the west block and assigns operational rights to Star Cement as the preferred bidder, subject to completion of statutory and contractual formalities.
