Aurubis’ Pirdop plant in Bulgaria is located around 70 km east of the capital, Sofia. It plays a key role in the Group’s network, processing copper concentrates and producing copper cathodes and anodes, as well as co-products like sulfuric acid and iron silicate.
The plant uses hundreds of electric motors in applications ranging from pumps, fans and compressors, through mixers, mills and conveyors, to gas blowers and cooling towers. However, a review of the equipment showed that the motor fleet needed to be modernized: more than half of the motors were over 25 years old and had been repaired multiple times over the years, while fewer than 5% reached IE2 or higher efficiency levels.
Aurubis sought a solution that would save energy, reduce emissions and help it meet its sustainability targets. With more than ten years of collaboration with ABB already behind it, Aurubis selected ABB as its partner for the project.
“We were looking for a partner who could provide cutting-edge solutions that align with our energy efficiency and sustainability goals,” says Biser Tsolov, Project Manager at Aurubis. “ABB has strong expertise and a proven track record in supplying high efficiency motors, drives and condition monitoring solutions, making it the ideal choice.”
“We began by conducting an Energy Appraisal and preparing a clear roadmap for the upgrade project,” says Daniel Dimitrov, Key Account Manager at ABB in Bulgaria. “We played an active role in the project planning, providing technical expertise and helping with feasibility studies and cost analyses. We also supported Aurubis in defining the requirements and preparing specifications. We worked closely with their team to ensure the motors and drives would be seamlessly integrated with the plant’s systems, and this created a solid basis for the project implementation.”
High efficiency motors
The IE5 motors in ABB’s scope of supply consist of 265 SynRM motors, which will be mainly used in variable torque applications like fans and pumps. They will be packaged with ABB ACS880 industrial variable speed drives (VSDs).
Of the IE4 motors, 181 are Process performance induction motors that will be used in constant torque applications like conveyors and mixers. Four two-speed motors will be installed for precise positioning of copper converters. Thirty-five of these IE4 motors will be supplied in motor-drive packages. ABB will also supply ten high efficiency direct drive RPM ACTM PM motors optimized to operate slow-turning cooling tower fans.
The ABB IE5 ultra-premium and IE4 super premium efficiency motors will provide an overall 28% reduction in energy consumption compared to the plant’s legacy motors. The 25 GWh annual energy saving is equivalent to the electricity used by around 6,250 average European households, and it will reduce carbon emissions by 12,000 tons per year. This supports both Aurubis’ sustainability targets and compliance with broader industry and governmental environmental standards.
The plant will also benefit by streamlining its motor sourcing activities. By working with ABB it has been able to transition from 42 different suppliers to a single partner. This enables much simpler spares inventory operations, and considerably reduced storage and management costs.
ABB IE5 SynRM motor 
ABB IE4 Process performance induction motors 
ABB ACS880 Industrial drives
Motor-drive packages
IE5 SynRM motors are always used with a drive, while IE4 induction motors deliver an additional 7-8% improvement in efficiency when paired with a VSD. Drives optimize energy efficiency and performance by adjusting the motor speed to the actual demands of the process. Ensuring precise motor control, they provide enhanced control of equipment, boosting flexibility in processes. As a leading supplier of both premium motors and drives, ABB delivers perfectly matched motor-drive packages optimized for their application.
ABB is supplying a total of 300 ACS880 industrial drives for the Pirdop plant’s upgrade. These drives are engineered for heavy use in harsh environments, with a durable design that enhances reliability. ABB industrial drives offer seamless integration with automation networks and enable flexible customization.
“This project is not only significant for the plant but also for the entire region,” says Bekir Bekirov, Local Business Manager at ABB in Bulgaria. “It’s being implemented in a phased approach and most of the work will be done during a scheduled shutdown in 2025, with all the equipment fully commissioned by the fall of 2025.”
Aurubis AG is headquartered in Hamburg, Germany and employs around 7,100 people worldwide. The Group is a global supplier of non-ferrous metals and a leader in copper recycling. It is Europe’s largest copper producer, specializing in the manufacture of high purity copper cathodes and other products. Aurubis is strongly committed to sustainability, and invests in resource efficiency, emission reduction and the advancement of recycling initiatives.
