For decades, Metsä Group has been doing long-term work to enhance energy efficiency, minimise energy consumption and continually increase its self-sufficiency in energy.
“The three factors that most affect Metsä Group’s energy efficiency are availability, the amount of water and the weather. We can’t control the weather, but we can influence availability,” says Pirita Mikkanen, VP, Energy, who is in charge of developing energy efficiency at Metsä Group
“Luckily, we have very competent personnel at our mills: they master their processes and know how to make the production plants run efficiently. Availability is a core concept in our energy efficiency.”
Pulp mills play a key role
Pulp mills play a key role in Metsä Group’s own energy production. Their surplus bioenergy is supplied as electricity to the grid, as heat to industrial customers and as district heat to nearby communities.
“The surplus energy from the mills is constantly supplied to the main grid, so the more our mills produce and save energy, the more of it will become available for distributing outside our company,” Mikkanen says.
The impacts of saving electricity
Metsä Group’s share accounts for 35 per cent of all the energy efficiency savings in Finland’s industrial sector since 2017.
“How much people save electricity in their homes directly affects their own finances, but the way our operators and other professionals act at our mills has an impact a thousand times bigger.
“We play a massive role in the Nordic energy management system as a producer of energy and one of the players that ensure security of supply. Due to the current energy crisis, however, these matters have risen to the agenda in a completely new way, because a shortage of energy is now also a possibility in our operating countries,” says Mikkanen.
The first step before other climate actions
Not only our wallets, but also the climate will benefit from the electricity-saving measures, because the more energy we save and the more efficiently we use it, the less emissions we generate.
“Energy efficiency efforts are the first step before other climate actions, because by reducing our energy consumption, we can reduce carbon dioxide emissions,” Mikkanen explains.
The renewable electricity produced by Metsä Group’s mills accounts for around five per cent of Finland’s overall electricity production. For bioelectricity, the share of production is nearly 20 per cent.
“The more efficient we are, the more we help our operating countries to be climate friendly. All the savings on bioelectricity that we generate are available for others to use.”
An energy-efficient mill is like a thermal bag
According to Mikkanen, the circular economy approach to heat, in other words the utilisation of heat multiple times, is the key to energy efficiency at the mills.
“An energy-efficient mill is like a thermal bag that prevents heat escaping. The heat is utilised several times and as effectively as possible.”
To keep the heat inside a thermal bag, it must not have any holes, and the lid must not be opened.
“This is also how our mills should function. As far as possible, they should use closed cycles for both heat and water, so that these resources can be utilised as effectively as possible.”
According to Mikkanen, this is optimally achieved at bioproduct mills, where the various processes take advantage of the different types of energy. Waste heat from one process may become operating heat for another - and nothing is wasted.