Using the case of outdoor shell jackets, this research studies obsolescence and potential lifespan extension by re-examining how product functionality, objectively and subjectively, develops over the course of product lifespans. In particular, the study focuses on second-hand stores for outdoor products. Functionality is indicated by user perceptions, visual assessments, laboratory measurements and price data, collected at first use, second-hand resale and end-of-life. Perceived functionality and price decline more rapidly (5–6 % per year) than assessed and measured functionality (around 3 % per year). This could be explained by properties related to appearance, which are not assessed nor measured but influence user perceptions and price. Discontentment regarding such properties appears more relevant for obsolescence than inadequate performance, suggesting the potential for design for attachment and timeless design. The relative stability of measured functionality over time suggests that a barrier for second-hand sales, concern about performance, could be ameliorated by a potential functionality-label.

It is increasingly clear that reaching environmental sustainability requires not only efficiency (reduced environmental impact per functionality) but also sufficiency measures (reduced environmental impact through reduced or changed functionality). Life cycle assessment (LCA) is a widely used tool to study environmental impacts related to consumption. However, because of the LCA convention of only comparing alternative products with equal functionality, it is currently inept as a method for assessing the environmental impacts of sufficiency measures. Against this background, this short paper aims to stimulate a discussion on how sufficiency measures can be assessed with LCA methodology. By analyzing the very few LCAs of explicit sufficiency measures in terms of the components of a functional unit (what function is provided, how much, for how long, and how well) features of a potential new branch of LCA methodology are outlined, called Sufficiency LCA. In Sufficiency LCA, product alternatives need to be similar enough so that the what component of the functional unit can be equal, while the other components, how much, how long, and how well, are allowed to be non-equal. Thus, a key feature of Sufficiency LCA concerns functional non-equivalence of compared product alternatives, which is not allowed or neglected in conventional LCA, but which could be allowed, acknowledged and quantified in Sufficiency LCA. Developing Sufficiency LCA could be critical considering that sufficiency measures are expected to be required, and that LCA is expected to be serviceable as decision-making support, in the transition toward environmental sustainability.

Life cycle assessment (LCA) is highly needed and widely used to assess the environmental performance of circular economy (CE) measures such as reusing and sharing. However, the results of such LCAs are hampered by limited knowledge about the use phase of consumer products and oversimplification of important use phase aspects such as product functionality, user behavior, displacement, and rebound effects. This paper aims to validate the usefulness of a framework designed to assist practitioners in the generation and utilization of such knowledge in LCAs of circular measures. To validate the framework, a case study is used: reuse of shell jackets enabled by “premium secondhand” stores for outdoor equipment and clothing. The paper demonstrates that conclusions about the environmental performance of reuse can easily be altered depending on the functional unit definition, whether real user behavior data are used, and whether imperfect displacement and rebound effects are considered. For instance, shell jacket life cycles that include reuse and thus may be labeled “circular” have significantly higher environmental impact per use occasion than “linear” ones (used by one principal user the entire lifespan), since “circular” shell jackets are used less frequently, in particular during their first use span. Through facilitating the generation and utilization of environmentally relevant use phase data, which are otherwise often overlooked, the framework seems capable of supporting a better understanding of the environmental performance of CE measures.

Life cycle assessments of circular economy measures (CE LCA) of consumer products have been criticized for oversimplifying important aspects of the use phase such as user behavior and rebound effects, limiting our understanding of the environmental performance of circular economy measures. This study tests the usefulness of a framework designed to facilitate accounting for such aspects, by applying the framework to a case study of reuse of shell jackets enabled by “premium secondhand” outdoor stores. Methods for collecting use phase data were user surveys and interviews with store managers. Using the framework on this case study generated several novel insights which are interesting in themselves and as inputs to CE LCA. For instance, secondhand shell jackets have a significantly lower frequency of use during their first use span compared to the second and to shell jackets in the linear reference scenario. This implies that reuse in this case does not function as a mere use extension of otherwise similar use phases as is commonly assumed. The generation of such insights, which hitherto have been lacking in CE LCAs, points to the usefulness of the framework as a tool for opening the “black box” of the use phase in CE LCAs to improve understanding of the environmental performance of circular economy measures.

Knowledge about obsolescence and its possible causes is instrumental to extend product lifespans. Product obsolescence may be caused by both subjective perceptions as well as objective and measurable deterioration of functionality. In order to extend lifetimes by avoiding and reversing obsolescence, this study addresses the current knowledge gap on how functionality of products develops over time, using a case study on shell jackets for outdoor recreational activities. Functionality over time is compared in terms of user perceptions, ocular assessments, laboratory measurements and, in addition, price. Data were collected at beginning of use, secondhand resale and end-of-life. In addition to ocular assessments and laboratory measurements, a survey was used to collect data from users on e.g. perceived functionality, price and duration of use span. Linear representations of perceived functionality and price decline more rapidly (5-6% per year) than assessed and measured functionality (both around 3% per year). This could be explained by properties such as appearance, which are included and seemingly important to user perceptions and price, but which are not assessed nor measured. The perception of such properties as low seems to be a more relevant cause of obsolescence than inadequate performance. This points to, for instance, timeless design to avoid obsolescence. The finding that measured functionality remains relatively high over time is important since concern about performance is a key barrier to secondhand sales. Information policy, such as performance-labelling, could thus contribute to reversing obsolescence. Future research could test the robustness of these findings as well as their generalizability to other products.

The importance of metals for modern society and future trends puts pressure on companies to handle issues concerning potential mineral resource scarcity (i.e. deficiency in quantity compared with demand). Companies see the need to handle such potential scarcity both in the short-term (is the availability constrained for our current products?) and the long-term (is our current use affecting the availability for future generations?). This study aims to examine the use of complementary methods for short and long-term scarcity in a company context, through a case study on permanent magnet electric traction motors, to provide both empirical and methodological insights. To mitigate long-term scarcity impacts, the results point to copper, neodymium and to some extent dysprosium as priority. These metals contribute to a large share of such impacts both due to themselves and their companion metals. In the short-term, neodymium and dysprosium, which are often regarded as critical (i.e. high supply disruption probability and high vulnerability to supply disruption), were found to be substitutable in the electric motor, reducing their criticality. Instead, the electric motor was most vulnerable to a potential supply disruption of iron and silicon because of no or low substitutability in electrical steel. Methodologically, these perhaps unexpected results, demonstrate that criticality requires a more context-specific assessment than often applied, especially regarding substitutability. By using complementary methods, decision-making about potential mineral resource scarcity impacts in company contexts could become more comprehensive and distinctly address both short and long-term scarcity impacts.

Life cycle assessment (LCA) research on the performance of circular economy (CE) measures such as reuse, repair and remanufacturing has been criticized for inadequate consideration of functional equivalency of circular compared to new products, allocation between use phases, displacement rates, rebound effects, product use and user behavior. For such reasons, it has been argued that our understanding of the environmental performance of CE is poor and over-optimistic. Motivated by these criticisms, this paper presents an outline of a conceptual framework developed to improve CE LCA research. The framework was developed through literature review, workshops and ongoing CE LCAs in the sport and outdoor sector. The paper overviews challenges related to mentioned criticisms and possible approaches to addressing them, presents a model for how aspects influential to CE LCA results interrelate, and, proposes a structure for describing product-user life cycles more accurately. The outlined conceptual framework could be an important step towards improving CE LCAs and, ultimately, our understanding of environmental outcomes of CE.