Stakeholder participation in sustainability assessment of non-wicked problems: The case of a future seaweed industry in Sweden.

Acceptance by, and cooperation with relevant stakeholders in developing new sustainability initiatives when they are generally perceived as positive, is one of the keys for successful implementation of such new sustainability initiatives later on. It is remarkable, however, that ample literature exists about involving stakeholders in research projects focusing on problems with diverging views (controversy) around facts and values (wicked problems), but there is very little literature addressing whether and how to involve relevant stakeholders in case of initiatives where diverging norms and values do not play a (substantial) role, like in sustainability assessment for a future seaweed industry. This perspectives paper addresses that gap, and explores how to design such sustainability assessment, illustrated by how stakeholder interaction influenced the assessment and its results for a future seaweed industry in Sweden, followed by a discussion whether and how a similar approach may benefit sustainability assessment of other non-wicked sustainability initiatives.

Comparison of different methods to include recycling in LCAs of aluminium cans and disposable polystyrene cups.

Many methods have been reported and used to include recycling in life cycle assessments (LCAs). This paper evaluates six widely used methods: three substitution methods (i.e. substitution based on equal quality, a correction factor, and alternative material), allocation based on the number of recycling loops, the recycled-content method, and the equal-share method. These six methods were first compared, with an assumed hypothetical 100% recycling rate, for an aluminium can and a disposable polystyrene (PS) cup. The substitution and recycled-content method were next applied with actual rates for recycling, incineration and landfilling for both product systems in selected countries. The six methods differ in their approaches to credit recycling. The three substitution methods stimulate the recyclability of the product and assign credits for the obtained recycled material. The choice to either apply a correction factor, or to account for alternative substituted material has a considerable influence on the LCA results, and is debatable. Nevertheless, we prefer incorporating quality reduction of the recycled material by either a correction factor or an alternative substituted material over simply ignoring quality loss. The allocation-on-number-of-recycling-loops method focusses on the life expectancy of material itself, rather than on a specific separate product. The recycled-content method stimulates the use of recycled material, i.e. credits the use of recycled material in products and ignores the recyclability of the products. The equal-share method is a compromise between the substitution methods and the recycled-content method. The results for the aluminium can follow the underlying philosophies of the methods. The results for the PS cup are additionally influenced by the correction factor or credits for the alternative material accounting for the drop in PS quality, the waste treatment management (recycling rate, incineration rate, landfilling rate), and the source of avoided electricity in case of waste incineration. The results for the PS cup, which are less dominated by production of virgin material than aluminium can, furthermore depend on the environmental impact categories. This stresses the importance to consider other impact categories besides the most commonly used global warming impact. The multitude of available methods complicates the choice of an appropriate method for the LCA practitioner. New guidelines keep appearing and industries also suggest their own preferred method. Unambiguous ISO guidelines, particularly related to sensitivity analysis, would be a great step forward in making more robust LCAs.

Multiple data sets and modelling choices in a comparative LCA of disposable beverage cups.

This study used multiple data sets and modelling choices in an environmental life cycle assessment (LCA) to compare typical disposable beverage cups made from polystyrene (PS), polylactic acid (PLA; bioplastic) and paper lined with bioplastic (biopaper). Incineration and recycling were considered as waste processing options, and for the PLA and biopaper cup also composting and anaerobic digestion. Multiple data sets and modelling choices were systematically used to calculate average results and the spread in results for each disposable cup in eleven impact categories. The LCA results of all combinations of data sets and modelling choices consistently identify three processes that dominate the environmental impact: (1) production of the cup's basic material (PS, PLA, biopaper), (2) cup manufacturing, and (3) waste processing. The large spread in results for impact categories strongly overlaps among the cups, however, and therefore does not allow a preference for one type of cup material. Comparison of the individual waste treatment options suggests some cautious preferences. The average waste treatment results indicate that recycling is the preferred option for PLA cups, followed by anaerobic digestion and incineration. Recycling is slightly preferred over incineration for the biopaper cups. There is no preferred waste treatment option for the PS cups. Taking into account the spread in waste treatment results for all cups, however, none of these preferences for waste processing options can be justified. The only exception is composting, which is least preferred for both PLA and biopaper cups. Our study illustrates that using multiple data sets and modelling choices can lead to considerable spread in LCA results. This makes comparing products more complex, but the outcomes more robust.

Environmental life cycle assessment of Ethiopian rose cultivation.

A life cycle assessment (LCA) was conducted for Ethiopian rose cultivation. The LCA covered the cradle-to-gate production of all inputs to Ethiopian rose cultivation up to, and including transport to the Ethiopian airport. Primary data were collected about materials and resources used as inputs to, and about the product outputs from 21 farms in 4 geographical regions (i.e. Holleta, Sebeta, Debre Ziet, and Ziway). The primary data were imported in, and analyzed with the SimaPro7.3 software. Data for the production of used inputs were taken from the EcoInvent®2.0 database. Emissions from input use on the farms were quantified based on estimates and emission factors from various studies and guidelines. The resulting life cycle inventory (LCI) table was next evaluated with the CML 2 baseline 2000 V2/world, 1990/characterization method to quantify the contribution of the rose cultivation chain to 10 environmental impact categories. The set of collected primary data was comprehensive and of high quality. The data point to an intensive use of fertilizers, pesticides, and greenhouse plastic. Production and use of these inputs also represent the major contributors in all environmental impact categories. The largest contribution comes from the production of the used fertilizers, specifically nitrogen-based fertilizers. The use of calcium nitrate dominates Abiotic Depletion (AD), Global Warming (GW), Human Toxicity (HT) and Marine Aquatic Ecotoxicity (MAET). It also makes a large contribution to Ozone Depletion (OD), Acidification (AD) and Fresh water Aquatic Ecotoxicity (FAET). Acidification (AC) and Eutrophication (EU) are dominated by the emission of fertilizers. The emissions from the use of pesticides, especially insecticides dominate Terrestrial Ecotoxicity (TE) and make a considerable contribution to Freshwater Aquatic Ecotoxicity (FAET) and Photochemical Oxidation (PhO). There is no visible contribution from the use of pesticides to the other toxicity categories. Production and use of greenhouse plastic are another important contributors, and just a bit less than the contribution of calcium nitrate to Abiotic Depletion (AD). The results of this study clearly indicate nutrient management and emissions from pesticide use, especially insecticides, as a focus point for environmental optimization of the rose cultivation sector in Ethiopia.

Environmental comparison of biobased chemicals from glutamic acid with their petrochemical equivalents.

Glutamic acid is an important constituent of waste streams from biofuels production. It is an interesting starting material for the synthesis of biobased chemicals, thereby decreasing the dependency on fossil fuels. The objective of this paper was to compare the environmental impact of four biobased chemicals from glutamic acid with their petrochemical equivalents, that is, N-methylpyrrolidone (NMP), N-vinylpyrrolidone (NVP), acrylonitrile (ACN), and succinonitrile (SCN). A consequential life cycle assessment was performed, wherein glutamic acid was obtained from sugar beet vinasse. The removed glutamic acid was substituted with cane molasses and ureum. The comparison between the four biobased and petrochemical products showed that for NMP and NVP the biobased version had less impact on the environment, while for ACN and SCN the petrochemical version had less impact on the environment. For the latter two an optimized scenario was computed, which showed that the process for SCN can be improved to a level at which it can compete with the petrochemical process. For biobased ACN large improvements are required to make it competitive with its petrochemical equivalent. The results of this LCA and the research preceding it also show that glutamic acid can be a building block for a variety of molecules that are currently produced from petrochemical resources. Currently, most methods to produce biobased products are biotechnological processes based on sugar, but this paper demonstrates that the use of amino acids from low-value byproducts can certainly be a method as well.