Energy efficiency has recently become a very hot topic, but Kuhmo sawmill has always paid attention to its energy usage, actively looking for ways to optimize and reduce consumption. One of the energy-efficient solutions implemented at the sawmill – which is located around 500 kilometers northeast of Helsinki – has been to use ultra-premium efficient motors and drives in all relevant applications.
"Energy is expensive, and efforts to save energy are a key aspect of doing business in a responsible and environmentally friendly way. We aim to adopt the most energy-efficient solutions, and this strategy has naturally helped us reduce our energy costs," says Tommi Ruha, Managing Director of Kuhmo Oy.
"We’ve followed how the technology of motors and drives has developed, and we’ve sought to utilize the latest optimized products," says Heikki Soininen, Electrical Automation Manager at Kuhmo.
SynRM motors and ACS880 industrial drives have always been an important part of the sawmill's energy efficiency toolkit. In 2017 ABB introduced IE5 ultra-premium efficiency SynRM motors with an option that makes them ideal for the timber drying application, and Kuhmo was the first sawmill in the world to install them in its drying process.
"At that time energy prices were at their normal levels, but Kuhmo were a step ahead with their strategy of saving energy by using ultra-premium efficient motors. They were pioneers who showed other timber producers the way forwards," says Olli-Petteri Karjalainen, Key Account Manager at ABB.
Tommi Ruha (left) Managing Director of Kuhmo, and Olli-Petteri Karjalainen, Key Account Manager, ABB. 
IE5 SynRM motors deliver ultra-premium efficiency. 
Heikki Soininen, Electrical Automation Manager at Kuhmo, with the ABB drives that are part of the sawn timber dry packaging line.
Major investment in energy-efficient production
Kuhmo is currently upgrading its entire sawmill with a EUR 50 million investment program. A third green sorting line, a new sawmill intake and a packaging plant have been built. A new saw line and two new channel dryers are under construction. The investments will increase Kuhmo’s annual production of sawn pine and spruce to 600,000 cubic meters.
"Almost all the dryer applications will be powered by SynRM motors and drives. In addition, we’ll be using regenerative drives – a new technology for us – at appropriate points in the process," Ruha explains. ABB's regenerative drives enable the energy normally lost in braking to be recovered, and this will reduce the need for cooling in areas where drives are installed.
Energy efficiency across the board
High efficiency motors make big energy savings possible, and when these savings are scaled up to plant level, Kuhmo could reduce its energy costs by a six-figure amount in the first couple of years alone.
The company has significant heat and electricity production on site. The power plant utilizes bark and wood chips, which are by-products of the sawmill’s processes, to generate all the heat energy and up to 70 percent of the electricity required annually.
"We aim for energy efficiency throughout our process - from the moment the raw material enters, to the point where the final product leaves," says Ruha. "Energy efficiency is important, and it will become even more important in the future. This is the way all businesses should operate: we should all strive to be responsible and use resources efficiently."
