The cement industry, known for its high energy consumption, faces increasing pressure to enhance efficiency and reduce environmental impact. ICR explores the critical role of energy management in cement manufacturing, highlighting the industry’s shift towards renewable energy, alternative fuels and advanced technologies to achieve sustainability. In the cement manufacturing process, energy consumption is a critical factor, significantly impacting both production costs and environmental sustainability. The industry is highly energy-intensive, with energy costs accounting for a substantial portion of the total production expenses.
According to International Energy Outlook (2016), the energy consumption of all industrial sectors around the World is increasing by an average of 1.2 per cent per year. The World’s industrial sector energy consumption expects to reach 309 quadrillions of British Thermal Units in 2040. The cement industry is one of the energy-intensive industries which utilises a sizeable amount of energy. Avami and Sattari (2007) found that the cement industries in Malaysia consumed about 12 per cent of the country’s total energy, while this value is 15 per cent in Iran. Hence, national and international efforts are carried out to reduce energy consumption and emission level in the cement industry.
In the cement industry, the total energy consumption accounts for 50–60 per cent of the overall manufacturing cost, while thermal energy accounts for 20–25 per cent (Wang et al., 2009; Singhi and Bhargava, 2010). The modern cement industry requires 110–120 kWh of electrical power to produce one ton of cement (Mejeoumov, 2007). Thermal energy is used mainly during the burning process, while electrical energy is used during the cement grinding process (Marciano, 2004).
Energy usage in cement manufacturing is primarily divided between thermal energy and electrical energy. Thermal energy is predominantly used in the kiln operation, where raw materials like limestone are heated to high temperatures to form clinker, the key component in cement. This stage consumes around 60-70 per cent of the total energy in the manufacturing process. The main fuel sources for thermal energy are coal, petcoke, and increasingly, alternative fuels derived from waste materials, which help in reducing carbon emissions. Electrical energy, on the other hand, is utilised across various stages, including raw material preparation, grinding, and cement milling. The grinding process, especially in the cement mill, is a significant consumer of electrical energy, often accounting for about 30-40 per cent of total electricity usage in the plant.
The energy consumption patterns vary depending on the technology employed, the type of fuel used, and the operational efficiency of the plant. Modern cement plants are adopting more energy-efficient technologies, such as preheaters, precalciners, and high-efficiency grinding systems, which help in reducing overall energy consumption. Additionally, there is a growing focus on optimising energy use through the integration of digital solutions and energy management systems, which can monitor and control energy consumption more effectively.
According to the report, Review on energy conservation and emission reduction approaches for cement industry, published December 2022, the energy consumption in cement production depends on the process through which it is manufactured. The dry process of cement manufacturing uses more electrical energy than the wet process, while the wet process uses more thermal energy than the dry process. The dry process of cement manufacturing utilises 75 per cent thermal and 25 per cent electrical energy. A maximum percentage of the total thermal energy is used for clinker production. According to the reports, the cement industry employs 90 per cent of the total consumed natural gas for clinker production in large rotary kilns (Fig. 6). For Indian cement industries, coal fulfills ninety-four per cent of the thermal energy demand. In contrast, the remaining need is fulfilled by fuel oil and high-speed diesel oil. The cement industry in India does not have sufficient natural gas available for fulfilling the thermal energy requirement (Karwa et al., 1998).
“Nuvoco has established a rigorous system for measuring and monitoring energy efficiency across its cement manufacturing processes.
Key metrics are tracked using advanced monitoring systems to ensure both optimal performance and strict regulatory compliance,” says Raju Ramchandran, SVP Manufacturing (Cluster Head – Central), Nuvoco Vistas.
“One critical aspect of this monitoring involves the consistent tracking of air emissions from fuel combustion in cement production and power generation operations. This includes pollutants like Oxides of Sulphur (SOx), Oxides of Nitrogen (NOx), and Particulate Matter (PM). Nuvoco employs Continuous Emission Monitoring Systems (CEMS) to observe these emissions in real-time, ensuring adherence to environmental standards,” he adds.
Renewable Energy Integration
Integrating renewable energy into cement production is an emerging strategy to enhance sustainability and reduce the industry’s carbon footprint. Traditionally reliant on fossil fuels, the cement industry is increasingly exploring renewable energy sources like solar, wind, and biomass to power various stages of production.
“Renewable energy is a fundamental component of Wonder Cement’s broader energy efficiency strategy. We have integrated renewable energy sources, such as solar and wind power, into our manufacturing operations to reduce our reliance on non-renewable energy. Our solar power plants, strategically positioned across our manufacturing sites, contribute significantly to our overall energy needs. By generating clean energy on-site, we not only reduce our electricity costs but also achieve substantial reductions in carbon emissions, underscoring our commitment to sustainability,” says Piyush Joshi, Associate Vice President – Systems and Technical Cell, Wonder Cement.
“Our approach to renewable energy extends beyond electricity generation. We are actively exploring the potential of renewable fuels for our kiln operations. Through partnerships with research institutions and technology providers, we are investigating the viability of hydrogen and other renewable energy sources to further reduce our carbon footprint and enhance energy efficiency,” he adds.
The use of Alternative Fuels and Raw Materials (AFR) in cement manufacturing plays a crucial role in reducing energy consumption and lowering the industry’s carbon footprint. AFRs, including waste-derived materials like industrial by-products and biomass, can replace traditional fossil fuels and raw materials in the production process. This substitution reduces the thermal energy required in kilns and lowers overall energy consumption.
Vikas Garg, Energy Manager, Udaipur Cement Works Ltd (UCWL), says, “Renewable energy plays a significant role in enhancing energy efficiency and reducing the carbon footprint in cement manufacturing. Integrating renewable energy into cement operations aligns with broader sustainability goals and helps in mitigating the environmental impact of the industry. We have reduced our needs of electricity from the grid by up to 50 per cent by utilising renewable energy.”
Additionally, AFRs enable energy recovery from waste materials, contributing to a circular economy by minimising the demand for non-renewable resources. The environmental and economic benefits of AFRs include reduced greenhouse gas emissions, lower landfill usage, and decreased reliance on costly fossil fuels. By integrating AFRs, cement plants can achieve greater energy efficiency and align with global sustainability goals.
MM Rathi, Joint President – Power plants, Shree Cement, says, “Renewable energy is a cornerstone of our strategy for energy efficiency and sustainability at Shree Cement. Our commitment to integrating renewable energy is reflected in our energy mix, where renewable sources account for 55.9 per cent of our total energy consumption. This significant share has enabled us to avoid 0.94 million tons of CO2 emissions, demonstrating our impact on reducing greenhouse gasses. Our total power generation capacity is 1 GW, with 50 per cent derived from renewable sources, including solar, wind and WHR.”
“Our energy management strategy leverages renewable energy to stabilise and optimise our energy supply. We are exploring advanced energy storage solutions, such as battery and pump storage systems, to manage the variability of renewable sources and ensure a consistent energy supply. Renewable energy is pivotal in achieving our sustainability targets, including substantial reductions in Scope 1 and Scope 2 emissions. By increasing our renewable energy share, we have significantly lowered our carbon footprint and contributed to global climate goals,” he adds.
Solar energy, for instance, can be harnessed for processes such as preheating raw materials, while wind energy can supply electricity for plant operations. Biomass, used as an alternative fuel, helps reduce dependency on coal and other fossil fuels in kilns. These renewable sources not only lower greenhouse gas emissions but also contribute to energy cost savings over time.
Raman Bhatia, Founder and Managing Director, Servotech Power Systems, explains, “Installing a solar system is just the first step; operating and maintaining it properly is equally important to ensure the system runs efficiently over the long term and for that we conduct regular inspections to detect and address issues like module degradation and inverter malfunctions early, preventing energy losses.”
“Our team ensures optimal performance through routine cleaning and maintenance, which maximises sunlight absorption and energy generation. Continuous performance monitoring using advanced data analytics allows us to optimise system settings, while preventive and corrective maintenance activities minimise downtime and equipment failures. By utilising techniques such as module-level monitoring and inverter tuning, Servotech ensures that solar systems operate at peak efficiency, delivering maximum energy output and long-term cost savings,” he adds.
The transition to renewable energy in cement production presents challenges, including the need for significant infrastructure investment and the variability of energy supply. Despite these hurdles, the growing emphasis on sustainability and regulatory pressures are driving the adoption of renewable energy, making it a critical component of the industry’s pathway to achieving net-zero emissions. Integrating renewables is not just about reducing carbon footprints; it also positions the cement industry as a leader in the global shift towards a more sustainable energy future.
Role of Technology and Maintenance
In cement manufacturing, managing energy efficiency is critical to reducing costs and minimising environmental impact. Predictive maintenance, understanding consumer machinery needs, and the integration of advanced technology play pivotal roles in achieving these goals.
Predictive maintenance uses data analytics
and real-time monitoring to anticipate equipment failures before they occur. By analysing machinery performance, cement plants can schedule maintenance activities proactively, reducing downtime and optimising energy use. This approach not only extends the lifespan of equipment but also ensures that machines operate at peak efficiency, minimising unnecessary energy consumption.
“When predictive maintenance is an integral part of a company’s maintenance practices it will increase equipment efficiency and directly impact the total energy consumed for the same output for any equipment,” says Dries Van Loon, Vice President – Products, Nanoprecise Sci Corp.
“With the Nanoprecise solution fully integrated, our end users not only receive actionable insights with defined ‘remaining useful life’, but also continuous data on the impact to energy consumption and its effect on carbon emissions. This is crucial in prioritising maintenance tasks not purely based on potential saved downtime and repair cost, but also on the highest energy impact, ensuring that maintenance tasks have a significant, measurable contribution to reducing carbon emissions,” he adds.
Understanding the specific machinery needs of consumers—such as the demand for high-efficiency kilns, grinding mills, and conveyors—enables manufacturers to tailor solutions that enhance energy efficiency. Customised machinery that meets the precise needs of a cement plant can significantly reduce energy usage, leading to more sustainable operations.
“Our customer-centric approach is pivotal in ensuring solutions are precisely aligned with the unique needs of the cement industry. With deep industry and domain expertise, our technical teams fully understand the specific challenges and requirements inherent in cement manufacturing. This knowledge allows us to offer tailored solutions that address the operational demands of the sector effectively. We engage closely with our customers to gain insights into their specific needs and operational contexts, leading to the creation and implementation of customised solutions. These solutions, designed with flexibility, allow seamless integration with existing plant infrastructure and processes and minimises disruptions during implementation, ensuring that new technologies enhance rather than disrupt current operations,” says Neeraj Kulkarni, Regional Division President – India, MEA & LatAm, Large Motors & Generators Division, ABB India.
“Furthermore, our commitment to continuous improvement is reflected in our iterative innovation process. By actively seeking and incorporating customer feedback, we refine and enhance our solutions to address emerging challenges and capitalise on new opportunities within the cement industry,” he adds.
The role of technology in managing energy efficiency extends beyond maintenance and machinery customisation. Digital solutions, such as energy management systems (EMS), IoT sensors, and artificial intelligence, provide real-time insights into energy consumption patterns. These technologies allow cement plants to monitor and optimise energy use across all stages of production, from raw material processing to clinker production and cement grinding. By leveraging these tools, plants can identify inefficiencies, implement corrective actions, and continuously improve their energy performance.
Challenges in Achieving Energy Efficiency
Achieving energy efficiency in cement manufacturing is a complex challenge due to several interrelated factors. One of the primary challenges is the inherent energy-intensive nature of the cement production process, particularly in the kiln operation where high temperatures are required to produce clinker. This stage consumes a significant amount of thermal energy, making it difficult to drastically reduce energy usage without compromising product quality.
The availability and cost of alternative fuels and raw materials also pose challenges. While alternative fuels can reduce energy consumption, their consistent supply and cost-effectiveness vary across regions, making it difficult for some plants to rely on them as a stable energy source. Furthermore, operational complexities such as fluctuating demand, varying raw material quality, and the need to maintain continuous production can limit the flexibility to implement energy-saving measures.
Finally, the regulatory environment can be both a motivator and a challenge. Stricter environmental regulations push companies towards energy efficiency, but compliance with these regulations often requires additional investments in technology and processes.
While the benefits of energy efficiency in cement manufacturing are clear, overcoming these challenges requires a balanced approach that considers both technological advancements and economic feasibility.
Conclusion
Energy efficiency is a critical component of sustainable cement manufacturing, offering significant benefits in terms of cost reduction, environmental impact, and regulatory compliance. However, achieving energy efficiency in this energy-intensive industry presents several challenges, from the inherent demands of the production process to the complexities of upgrading aging infrastructure and integrating
new technologies.
The adoption of alternative fuels and raw materials (AFR) has shown promise in reducing energy consumption, but consistent supply and cost remain obstacles. Similarly, renewable energy integration, while essential for long-term sustainability, requires significant investment and careful management to overcome the variability of energy supply.
Predictive maintenance and the use of advanced technology play pivotal roles in optimising energy use, allowing cement plants to operate more efficiently and with reduced downtime. By understanding the specific needs of consumer machinery, manufacturers can tailor solutions that further enhance energy efficiency, aligning operations with both economic and environmental goals.
Despite these challenges, the cement industry is gradually moving towards a more energy-efficient future. The integration of digital solutions, renewable energy, and innovative maintenance practices are paving the way for a more sustainable and cost-effective production process. As the industry continues to evolve, the focus on energy efficiency will be crucial in driving progress towards a low-carbon economy and ensuring the long-term viability of cement manufacturing.
– Kanika Mathur
