How the Schaeffler plant in Kappelrodeck is sustainably transforming its production with technotrans
The Schaeffler Group's Kappelrodeck plant compellingly demonstrates that investments in sustainability can be both economically viable and efficient. On its journey to becoming a CO2-neutral site, the company has implemented an intelligent central cooling concept. At the heart of this initiative is a container cooling system from thermomanagement specialist technotrans. This future-proof and sustainable solution utilizes the natural refrigerant R290 (propane) and operates with exceptional energy efficiency. The cooling concept now serves as a model for other Schaeffler plants.
The Schaeffler Group, headquartered in Herzogenaurach, is one of the world's largest family-owned companies, employing around 84,000 people. The corporation operates in three sectors: Bearings & Industrial Solutions, Vehicle Lifetime Solutions, and Automotive Technologies. Since 2018, the headquarters of the Automotive Technologies division has been located in Bühl, which includes the plants in Bußmatten, Sasbach, and Kappelrodeck. A significant focus of this division is on transforming mobility towards climate-friendly drives. To further this goal, Schaeffler established the e-mobility division in 2018, developing components and system solutions for all types of electric drives—from e-bikes to commercial vehicles and sports cars. This includes asynchronous machines, permanently excited synchronous machines, axial flux motors, and magnet-free e-motors, known as externally excited synchronous machines. Schaeffler also contributes to emission-free mobility through key components for fuel cells.
“We develop and manufacture tools here in Kappelrodeck for the entire spectrum,” reports Andreas Glaser, an Industrial Engineer responsible for process development and procurement of necessary manufacturing machinery at the Schaeffler plant. The facility produces stamping and forming tools, assembly tools, injection moulding tools for plastics, prototypes, as well as fixtures and operating resources for its own production. Highest precision is essential for manufacturing processes: “We require absolutely stable climatic conditions in our production halls to eliminate fluctuations in the accuracy of our metalworking machines,” emphasizes Glaser. “Previously, nearly 70 small cooling devices delivered directly with the processing equipment dissipated process heat into the hall environment. As precision demands increased, we reached a limit where fluctuations became too significant.” A new solution was necessary to sustainably dissipate heat loads and ensure accuracy in production.
Well-thought-out energy management
As the energy officer at Schaeffler for the Bühl site, Tobias Szargan had clear ideas about what factors needed consideration: “The waste heat from the cooling devices was directed into the hall, increasing energy consumption and deteriorating workplace conditions. On hot summer days, this led to machine failures.” The goal was to harness the waste heat from the metalworking process while reducing the number of cooling devices. The 70 compact units occupied significant space in production and incurred substantial maintenance costs. “Moreover, all small devices used climate-damaging chemical refrigerants,” says Szargan. Instead of many individual devices, Szargan aimed to establish a process cooling network with a central cooling supply utilising a natural refrigerant.
Together with Glaser, Szargan defined the requirements for the new cooling concept at Schaeffler's site. Determining the actual cooling capacity needed for a central supply proved particularly challenging: “Typically, the cooling devices supplied with processing machines are oversized. Summing up the nominal capacities indicated on individual devices is therefore not effective. Additionally, our toolmaking is very agile. Establishing secure calculation bases was one of the most difficult tasks in this project; however, we managed it with some uncertainty,” explain the project leaders. Over several summer months, they conducted performance measurements on some processing machines to derive total demand from all machinery in a worst-case scenario. The result: The system should initially provide 270 kilowatts of cooling capacity and be expandable for future needs.
Natural refrigerant as a future-proof solution
In the next step, Schaeffler brought technotrans on board. Since their ideas and requirements could not be realised with an “off-the-shelf” solution, Schaeffler relied on their trusted refrigeration technology partner. “We have already successfully completed several projects together. Technotrans operates very customer-oriented and at a high technical level. From kick-off to acceptance testing, we always felt well-supported,” emphasizes Szargan. This provided an excellent foundation for the new initiative. With support from regional sales manager Stephan Untraut and sales manager Tobias Escher from technotrans' Meinerzhagen location, the project took shape. “Our primary goal was to establish a sustainable and intelligent central cooling supply,” explains Szargan. “A major challenge was moving away from chemical refrigerants that harm the environment—something that has received little attention in industrial settings so far.”
A central concern for Schaeffler's energy officer was using a natural refrigerant with low Global Warming Potential (GWP). For context: Conventional HFC refrigerants like R407C (GWP 1774) or R134A (GWP 1430) have four to five thousand times higher greenhouse gas potential than CO2. From 2027 onwards, new systems may only use refrigerants with a GWP of a maximum of 750. Currently, government support for systems is only available if GWP values are below 150. With stricter regulations under the F-Gas Regulation phase-down, quantities of partially fluorinated hydrocarbons in the EU will continue to decrease. “Refrigerants with higher GWP will thus become scarce, less available, and unpredictably more expensive,” emphasizes Szargan.
Technical room in shipping container makes it possible
Schaeffler opted for the future-proof natural refrigerant R290 (propane), which has a GWP of just 0.02. As propane is flammable, it imposes strict safety requirements regarding fire protection. Additionally, concerns arose regarding where to install large and heavy components of the system due to space constraints within production facilities; neither roof space nor new construction options were feasible due to structural or cost issues. The breakthrough idea came from technotrans: A shipping container converted into a technical room houses all pumps, tanks, refrigeration units, coolers, and control cabinets. “By placing it outside against the back wall of the hall, we did not have to sacrifice valuable production space inside,” says Szargan.
Szargan was surprised by how little refrigerant was needed despite propane's lower efficiency: “I expected two times 30 kilograms; actually, the cooling system is filled with two times eleven kilograms of propane gas—equivalent to two standard gas bottles used for home barbecues.” Another advantage of this solution lies in its flexibility: both container and cooling system are expandable and can be easily relocated if building changes occur.
Demand-oriented supply combined with heat recovery
Production in Kappelrodeck is divided into three segments. The highest demands for process cooling come from wire erosion processes integrated into a cooling water circuit with an inlet temperature of 14 degrees Celsius. Other machining processes such as milling and turning require a base temperature of 20 degrees Celsius; while a third segment does not require cooling water at all. “By not solely supplying the hall with a 14-degree cooling water network but additionally utilising a second circuit with 20-degree water, we save enormous amounts of energy,” explains Szargan.
Technotrans and Schaeffler also efficiently designed heat recovery from process heat: The waste heat generated during cooling in the central refrigeration unit reaches temperatures of 55 degrees Celsius and can then be used as warm water for heating buildings or other processes. Technotrans feeds this into a 3,000-litre water buffer tank. “We utilise heat from the refrigerant to generate warm water,” explains sales manager Tobias Escher.
Winter relief enhances energy efficiency
The so-called free cooling via glycol coolers alleviates pressure on refrigeration systems during winter months; at low outdoor temperatures, cold can be produced more efficiently and cost-effectively than with conventional refrigeration units. Both cooling water circuits are equipped with such winter relief systems. “When we need less heat than we generate during winter operations, we can completely do without refrigeration units,” states industrial engineer Glaser.
The free cooler is also employed when heating systems do not require energy—such as on Sundays or during summer months—where excess waste heat from refrigeration is released into the environment via rooftop coolers to relieve pressure on refrigeration systems and recondense refrigerants back into liquid form. This also aids climate control within production halls since waste heat no longer heats hall air as before.
Efficient installation minimising operating costs
The installation required only brief but planned production interruptions to progressively connect manufacturing machines to their new cooling network; during this time technotrans installed piping alongside ongoing production while providing Schaeffler with temporary cooling units at startup. “This allowed us to build up the central cooling system behind-the-scenes while connecting lines without further interruptions,” reports industrial engineer Glaser. Moreover, essential components from technotrans were pre-installed within containers significantly reducing construction time on-site; “This installation solution is top-notch,” emphasizes Glaser.
The thermomanagement specialist designed Kappelrodeck's refrigeration system optimised for operating costs according to technotrans regional sales manager Stephan Untraut’s specifications: “This initially led to higher investment costs; however, Schaeffler benefits significantly from reduced operational costs along with government subsidies.” In addition to savings potential, Schaeffler gains further advantages; future investments in new metalworking machines will eliminate both refrigeration units as well as their maintenance needs; ventilation requirements can also be downsized accordingly; “We anticipate longer service times for production machines due to improved environmental conditions; not least do employees appreciate better air quality within halls—all these soft factors are hard to quantify,” summarizes Szargan.
Goal: First CO2-neutral site within Schaeffler Group
“The combination of intelligent regulation systems alongside natural refrigerant generation and heat recovery feeding into heating networks is unique within Schaeffler,” emphasizes Szargan. As part of its Energy Efficiency Programmes Bühl aims to save nearly 1.5 gigawatt-hours by 2024; globally nearly 100% green electricity is sourced by Schaeffler Group meaning no CO2 equivalents have been accounted for since 2020 when calculating electricity emissions; additionally plans are underway this year to install photovoltaic systems on Kappelrodeck’s rooftop enhancing self-generated renewable energy output further still; “Only our gas-fired building heating still needs substituting—a goal achievable through utilising waste heat from production processes—making Kappelrodeck Schaeffler Group’s first CO2-neutral site,” states Szargan.
Schaeffler and technotrans have already completed six joint projects; further initiatives aimed at optimising sustainability at Bühl are already planned: “Economic benefits can be realised through energy transformation along with many resulting advantages—one simply needs to seize opportunities understand them implement them effectively—the centralised cooling supply at Kappelrodeck epitomises this,” concludes energy officer Szargan.
For more information visit: www.technotrans.com and www.schaeffler.com