Promising sustainability results for Metsä Group’s Kuura textile fibre

In 2024, a new Life Cycle Assessment (LCA) of the Kuura® textile fibre was conducted. The assessment, based on a hypothetical industrial-scale plant of 100,000 tonnes of Kuura® fibre per year, was carried out by an external expert organisation, Etteplan, who applied the well-known, ISO standardised methodology for the assignment.

The outcome of the assessment is very promising (Figure 1). For example, when comparing to commercial man-made cellulosic fibres (viscose and lyocell), and to cotton fibre, large-scale production of Kuura® fibre, applying the Metsä Group concept, would result in clearly lower level of greenhouse gas emissions (in the methodology known as “global warming potential”). This outcome supports well our goal of developing a competitive alternative to the textile fibre market.

Figure 1. The relative cradle-to-mill gate global warming potential (fossil, kg CO₂ eq.) for one tonne of cellulosic staple fibres. (Cotton: fibre production, Ecoinvent 3.10; Viscose, Austria: European beech, integrated production, biomass & recovered energy from MSWI; Lyocell, Austria: eucalyptus and beech, separate pulp production, energy 70% gas & 30% biomass; Lyocell 2012, Austria: eucalyptus and beech, separate pulp production, 100% recovered energy from MSWI). The bars in the figure are normalised in height so that the viscose result represents 100%.

The Kuura® textile fibre would be produced from softwood Kraft pulp (i.e., paper-grade pulp), not from dissolving pulp, which is commonly used as raw material in the production of man-made cellulosic fibres. The wood for the pulp production would, in turn, be procured from forests located close to the pulp and textile fibre mills. A significant share of the forests in question are today owned by owner-members of Metsä Group’s parent company.

The Äänekoski bioproduct mill (i.e., the unit producing the pulp for the demo plant) is a greenfield investment that was started up in 2017. The bioproduct mill operates without any fossil energy and it is one of the most modern pulp-producing mills globally. This setup results in the mill generating significant amounts of renewable energy (steam, electricity, etc.) in excess. This excess, in turn, would be used as the source of energy, when producing the Kuura® textile fibres. Integrating textile fibre production to such an efficient host mill would result in a multitude of environmental benefits, as shown by the LCA exercise.

The LCA was made according to ISO 14040:2006 and ISO 14044:2006 standards for LCA studies and ISO 14067:2018 standard for carbon footprint studies applying a cradle-to-mill gate system boundary. The LCA work and the comparison to alternative fibres were both critically reviewed by a third party (RISE Research Institutes of Sweden). No major cut-offs were included in the assessment. Inventory data of Kuura® production was based on the newest available mass and energy balances for a possible 100,000 tonnes per year commercial mill integrated to Metsä Group’s bioproduct mill in Äänekoski, Finland. The data used to assess the references was collected from well-known scientific sources where cotton fibre production value is from Ecoinvent 3.10 and man-made cellulosic fibres are produced in Austria by different processes.^*)

Additional material: 

250127 Life cycle assessment of Kuura textile fibre 2024_Summary report.pdf

Comparing the environmental performance of Kuura fibre® with the alternative cellulosic fibres v2 December 20 2024.pdf

Final critical review statement Metsa Fibre Kuura 08-11-2024.pdf

Critical review statement Comparing the environmental performance of Kuura® fibre with the 08-01-2025.pdf

^*)Shen, L.; Patel, M.K. Life Cycle Assessment of man-made cellulose fibres (2010) Lenzinger Berichte, volume 88, pp. 1 - 59