Metsä Board Husum mill’s high-efficiency motors save 83,000 kilowatt hours of power every year
Metsä Board’s Husum mill is located on the east coast of Sweden. The integrated board and pulp mill produces folding board, white kraft liner and pulp. The operators aim for the facility to be at the forefront of the industry for sustainability. The company’s targets are even more ambitious than Sweden’s national 2030 target of increasing efficiency by 50 percent compared with 2005 levels.
The plant needed to upgrade six older 30-kilowatt (kW) DC motors which were used to drive the filter drums in one of the bleachers. The motors operate almost constantly – approximately 8,600 hours per year – so any opportunity to improve their energy efficiency would result in significant emission and cost reductions.
Metsä Board selected ABB’s most efficient solution, SynRM motor-drive packages, to replace the old motors. Compared with the IE2-rated induction motors, the SynRM models achieve 60 percent lower losses.
Compared with the existing motors, each SynRM motor saves an average of 13,900 kilowatt-hours (kWh) per year. The six motors, combined with ABB ACS880 drives, save more than 83,000 kWh per year – the equivalent amount of electricity used to power approximately four Swedish households.
These energy savings mean that the motors are also more cost-effective to operate. The cost of upgrading to high-efficiency models pays for itself in just 18 months.
“We want to be at the forefront of the industry in this regard. Metsä Group has a visionary view of achieving low energy consumption, and the most effective way to achieve our self-sufficiency targets is to use less energy while producing the same amount of product. That is why the SynRM project is important: by choosing energy-efficient motors, we get higher availability and lower energy consumption at the same time,” explains Elias Agrell, Automation Engineer at Husum.
“Replacing the older DC-motor with efficient IE5-motors offers great energy savings and a short payback time for the investment,” says Stellan Rosenquist, Product Marketing Manager at ABB Motion, Sweden. Additionally, the lower losses in the motors will decrease the temperature rise, and increase service intervals, and the overall lifetime. In summary, this investment lowers the total life cycle cost for the owner.”
