LCA on fast and slow garment prototypes

Rapport, 2018

This report summarises the environmental assessment work done in the Mistra Future Fashion program focussed on the potential to improve the environmental performance of garments and adapt them to a circular economy. The approaches examined in this report include reducing the environmental impacts from fast-fashion trends by making garments from paper-based materials, or by extending garment life cycles.

This assessment considers two paper-based garments. One is made primarily from paper pulp but enhanced with a polylactic acid polymer. This garment is worn between two to five times before being recycled as newspaper. The other fast garment is made of paper pulp, polylactic acid and nanocellulose. It has a similar life cycle but is composted after use life. These garments are compared with a standard t-shirt. The report also considers a slow-paced scenario in which a polyester garment passes between several owners and is regularly changed to maintain its appeal. It is updated with a transfer sublimation overprint three times, making the garment darker each time. Later it is joined with an outer shell of new material using laser technology to
make a cropped, box-cut jacket.

The assessment was performed using environmental life cycle assessment. More particularly, the assessment was based on attributional process analysis with cutoff allocation procedures and comparison with a traditional reference garment life cycle. Key environmental effect categories considered here include climate change (greenhouse gas emissions), freshwater eutrophication, freshwater ecotoxicity and human toxicity (cancer and non-cancer).

The results indicate that the environmental outcomes of the paper-based garments can be competitive with the reference garment, particularly when the user is assumed to throw away a fully functional reference garment after five uses. This assumption may be true for some users, but the number of uses is considerably lower than the typical or the potential lifespan of the reference garment. The main factor assisting the paper-based garments is the reduction in the impacts per mass associated with material manufacturing (fibres, spinning, knitting), and also their lighter masses. Avoided impacts in the use phase play a secondary role on account of their location in Sweden with its low-carbon energy mix. The long-life garments are also competitive
compared with their reference garments. This is primarily a consequence of how extending garment life avoids the production of new garments. The environmental impacts associated with transfer sublimation dye reprinting and laser processing do not significantly impact the overall environmental performance of the extended longlife garments, though confidentiality of data prevents a full assessment of these.

The garments in this report are pilot products and explorative scenarios rather than attempts to model existing business or behavioural patterns. The reader should therefore take care to keep the results in context when interpreting them. Nevertheless, the results suggest the value of pursuing the potential associated with these garment life cycles. We should also bear in mind that while the reference garments in this assessment are based on typical usage patterns, other more sustainable patterns are feasible.