This Month in Journals: The First Life Cycle Analysis of Skis

For the first time, a group of researchers published a life cycle assessment for the production of skis. Published in the Journal of Industrial Ecology, Tobias Luthe, Thomas Kagi and Jan Reger examined how a pair of skis made by Grown, a Munich-based manufacturer specializing in ecologically-friendly freeride skis, compared to an average alpine ski.

“One pair of skis may not considerably affect the environment, but the world market in the season 2004-2005 of about 4 million pairs of Alpine skis and about 1.4 million pairs of Nordic skis sold, and about 3.2 million Alpine skis in the season 2009-2010 reveals the importance of sustainable ski design,” the authors wrote in their introduction.

The analysis performed was a “cradle-to-grave” assessment starting at where the raw materials come from, going through production and distribution and ultimately ending with when the skis were discarded.

While the assessment was performed for alpine skis, meaning that material like steel for the edges can be ignored, many aspects would be relevant for nordic skis as well, for instance the polyethylene bases, which must be granulated at a plant, and the wooden cores, which must be awn and kiln dried. All of the materials must be not only harvested but transported to and from production and then to sales and consumers. The authors also considered how much energy went into the fabrication process itself.

Some nordic skis, like Fischer’s Vasa series and their Superlight Crown and Wax skis, already use a basalt core, which was also examined in the life cycle analysis. This replaces heavily-manufactured fiberglass and/or carbon fiber.

In terms of greenhouse gas emissions, the entire process of producing freeride alpine skis released about 16.4 kg of CO2 per single Grown ski and 22.6 kg of CO2 per conventional ski. About a third of this came from the materials themselves and 60 percent from production.

(This 45.2 kg of CO2 compares to, after a quick web search, about 240 kg of emissions that go into the production of your average bicycle; flip flops weigh in at 9 kg while hiking boots are more like 90 kg. The light weight of a pair of skis is a big advantage.)

The Grown ski saved 30 percent of the energy of a conventional ski because the company selected environmentally-friendly materials, for instance having a cherry wood top-piece that was simply varnished instead of using a conventional plastic top sheet, which adds 7 percent to the materials footprint. The analysis showed that 60 percent of the energy form packaging could be saved just by using recycled cardboard for boxes.

Major savings could also be made at “end of life”: the authors suggested upcycling old skis.

“In an upcycling scenario the ski is put back to use as a valuable resource for structural parts in furniture,” they wrote. “Mattress supports in bed frames that require a high flex and stability can be constructed from old skis. The customer is offered an incentive to send back skis that are no longer in use, thus giving the ski a second life.”

In the nordic ski industry, some steps have been taken. Fischer has advertised since 2009 that all of its ski production is done with renewable energy, primarily biomass; the Atomic factory in Altenmarkt uses a wood-pellet heating system. In 2010 Madshus removed PVC from its entire boot product line, in an effort to be more sustainable. Rossignol has an environmentally-certified manufacturing plant for its bindings. The Salomon website is one of the few to list an environmental policy, but has no details on how it should be accomplished.

How much of a difference does this make? It’s unclear. The new paper also notes that a single trip driving to a ski area outstrips the entire carbon footprint of ski production and distribution. Getting to the mountains is the biggest environmental flaw in skiing. This is a bit easier for nordic enthusiasts: the luckiest can ski out the backdoor or in city parks. But getting to a truly beautiful natural setting for your ski requires some fuel in most situations.

In conclusion, the authors offered up two thoughts. The first is that despite the savings the Grown ski made in carbon footprint, skis can go farther. More ecologically-friendly glues could be found and potentially some materials could be used that are byproducts of other manufacturing processes.

Secondly, consumers may be willing to invest in skis that are more sustainable. A survey of Grown customers in the 2009-2010 season showed that the environmental footprint of their skis was the second-most important factor in purchasing decisions; price was all the way down in sixth place.

“The balancing process between environmental optimization, social acceptance, technical feasibility, and economic efficiency remains difficult to address,” they wrote. “… We see the general responsibility of the industry and the need to inform the customer accordingly about products in order to reduce complexity and provide transparent information on the impacts of a product and the way individual consumption affects the system.”

Of note: The authors also wrote that the European market for skis is roughly half what it was a decade ago.

Link to article abstract (full article available by subscription only)