The ELECTRA consortium comprises 17 partners from 8 countries, each bringing specialized expertise across the cement, lime, and pulp process industry value chains. These partners include entities involved in basic and applied research, technology provision, end-user applications, societal sciences, and business development.

Arvid Stjernberg, the Head of Application and Development at Heidelberg Materials, discusses the unique initiative to showcase how electric heating can substitute fossil fuels to decarbonize industries that rely on extremely high temperatures for production.

The essence of the ELECTRA project

Arvid Stjernberg, Head of Application and Development, Heidelberg Materials."This project represents a critical step forward in our mission to understand and implement electrification for industrial processes," explains Stjernberg. "We started exploring electrification in 2018, but the ELECTRA project takes it to a new level. It’s an unparalleled opportunity to work alongside some of Europe’s brightest minds and cutting-edge technologies."

Stjernberg highlights the importance of the consortium's collaborative efforts. "The strength of this project lies in the diverse expertise each partner brings," he says. "At Heidelberg Materials, our role centers on creating a plasma-driven rotary kiln capable of reaching the high temperatures required for cement production."

In addition to the rotary kiln development, Heidelberg Materials is involved in testing at VTT’s facilities in Finland, where much of the project’s research on calcination processes is conducted. "This project is about more than individual breakthroughs," he emphasizes. "It’s about a shared vision for a sustainable future. Together, we’re proving that electrification can transform industrial processes in previously unimaginable ways.”

Technical aspects: A collaborative heating process

Kanthal’s resistance heating is central to the calcination phase, operating at around 900–1,000°C (1,652–1,832°F), while plasma heating takes over for the sintering stage, reaching temperatures above 1,300°C (2,372°F).

The project highlights the complementary roles of different electric heating technologies where Kanthal’s resistance heating is central to the calcination phase, operating at around 900–1,000°C (1,652–1,832°F), while plasma heating takes over for the sintering stage, reaching temperatures above 1,300°C (2,372°F). Together, these technologies form a seamless two-part heating process that meets the diverse temperature requirements of cement manufacturing.

“Kanthal’s resistance heating solutions are perfectly suited for the calcination phase,” Stjernberg says. “By preheating materials efficiently, they lay the groundwork for plasma heating to handle the high-temperature demands of sintering.”

“Each technology plays a critical role in ensuring a smooth, efficient production cycle,” Stjernberg elaborates. “The combination of resistance and plasma heating allows us to achieve the temperatures we need while advancing our sustainability goals.”

Stjernberg regards the alliance with Kanthal on heating technology as invaluable. “Rather than simply buying services, we are co-creating solutions,” he remarks. This collaborative model fosters mutual understanding and accelerates innovation, enabling both partners to effectively address each other’s technological needs and challenges.

Driving innovation with plasma-driven kilns

The construction and testing of a plasma-driven rotary kiln represent a technological shift with the potential to revolutionize traditional cement production. Heidelberg Materials will begin initial tests in a 300-kilowatt kiln at its Slite cement plant in Gotland, Sweden, before scaling up to a 1 MW rotary kiln at its Krabbe plant.

Stjernberg explains, “Scaling up is not just about adding more power. It’s about achieving what engineers call the ‘technology readiness level’ (TRL), which ensures that plasma heating is viable on an industrial scale.”

Plasma-driven kilns offer distinct advantages over conventional heating methods, particularly for high-temperature applications like cement production, where sintering requires temperatures of up to 1,500°C. “Plasma allows us to reach these extreme temperatures efficiently,” Stjernberg emphasizes. “This efficiency is crucial as we work to decarbonize our operations and transition to cleaner energy sources.”

Stjernberg further highlights the importance of this development: “This isn’t just about improving existing methods—it’s about fundamentally rethinking how we approach industrial heating. Plasma technology gives us a pathway to drastically reduce emissions while maintaining the performance our industry demands.”

The project marks a critical advancement for Heidelberg Materials, aligning the company’s innovative efforts with its commitment to sustainability and cleaner energy.

Electrification’s role in CO₂ capture

A major environmental benefit of switching to electric heating lies in its impact on CO₂ emissions, particularly during the calcination process where calcium carbonate is heated to extreme temperatures to produce lime.

Conventional calcination relies on fossil fuels, which mix CO₂ with other gases, requiring complex and energy-intensive separation techniques. “By using electricity, we can release nearly pure CO₂—not mixed with other gases like in fossil fuel-based processes,” stresses Stjernberg. “This significantly simplifies the capture process and makes carbon capture far more efficient and cost-effective.”

While Heidelberg isn’t directly responsible for developing carbon capture technology within the ELECTRA project, the electrification strategy itself addresses one of the core challenges in cement production.

Overcoming the challenges

Changing age-old habits and methods comes with a lot of learning and unlearning, and transitioning to electric heating in cement production is no exception. Adapting to new technologies requires maintaining consistent high temperatures, optimizing the durability of heating elements, and ensuring energy efficiency—key areas that Heidelberg Materials, Kanthal, and partners are addressing through collaboration in the ELECTRA project.

“Scaling up from pilot tests to full-scale operations is a critical step,” explains Stjernberg. He believes that the insights gained through ELECTRA will provide a roadmap for designing optimal systems. “This project isn’t just about making electric heating feasible—it’s about redefining its potential advantages for the cement industry,” Stjernberg adds.

Future prospects

Looking ahead, Stjernberg remains optimistic about the transformative potential of electric heating in the cement industry.

Stjernberg envisions even larger pilots and deeper collaboration with partners like Kanthal as the next steps. “If this project succeeds, it could open the door to an even bigger pilot and ongoing collaboration, with the ultimate goal of making electric heating a standard in the cement industry,” he shares.

For Heidelberg, the success of ELECTRA represents more than a technological milestone—it symbolizes a paradigm shift in sustainable manufacturing. By demonstrating the feasibility and advantages of electric heating, the project not only aims to transform cement production but also sets an inspiring benchmark for other high-emission industries. As Stjernberg puts it, “This is just the beginning of what’s possible when innovation and collaboration come together.”