Life Cycle Assessment

SETAC Europe Young Scientist LCA award 2019 for P. James Joyce Abstract At the 29th SETAC Europe annual meeting, May 26–30, 2019, Helsinki (Finland), P. James Joyce received the SETAC Europe Young Scientist LCA Award 2019. James is an environmental scientist by formation (University of Cambridge/Imperial College London), and finished his PhD in 2019 (KTH Institute of Technology, Sweden). His PhD research focused on the environmental considerations related to valorization of Bauxite residue. Herein, James leveraged his deep fundamental understanding of LCA and programming skills to assess the environmental impacts associated with complex valorization pathways.

EcoBalance 2018—Nexus of ideas: innovation by linking through life cycle thinking (9–12 October 2018, Tokyo, Japan)

The integration of long-term marginal electricity supply mixes in the ecoinvent consequential database version 3.4 and examination of modeling choices Abstract Purpose The long-term marginal electricity supply mixes of 40 countries were generated and integrated into version 3.4 of the ecoinvent consequential database. The total electricity production originating from these countries accounts for 77% of the current global electricity generation. The goal of this article is to provide an overview of the methodology used to calculate the marginal mixes and to evaluate the influence of key parameters and methodological choices on the results. Methods The marginal mixes are based on public energy projections from national and international authorities and reflect the accumulated effect of changes in demand for electricity on the installation and operation of new-generation capacities. These newly generated marginal mixes are first examined in terms of their compositions and environmental impacts. They are then compared to several sets of alternative electricity supply mixes calculated using different methodological choices or data sources. Results and discussion Renewable energy sources (RES) as well as natural gas power plants show the highest growth rates and usually dominate the marginal mixes. Nevertheless, important variations may exist between the marginal mixes of the different countries in terms of their technological compositions and environmental impacts. The examination of the modeling choices reveals substantial variations between the marginal mixes integrated into the ecoinvent consequential database version 3.4 and marginal mixes generated using alternative modeling options. These different modeling possibilities include changes in the methodology, temporal parameters, and the underlying energy scenarios. Furthermore, in most of the impact categories, average (i.e., attributional) mixes cause higher impact scores than marginal mixes due to higher shares of RES in marginal mixes. Conclusions Accurate and consistent data for electricity supply is integrated into a consequential database providing a strong basis for the development of consequential Life Cycle Assessments. The methodology adopted in this version of the database eliminates several shortcomings from the previous approach which led to unrealistic marginal mixes in several countries. The use of energy scenarios allows the evolution of the electricity system to be considered within the definition of the marginal mixes. The modeling choices behind the electricity marginal mix should be adjusted to the goal and scope of individual studies and their influence on the results evaluated.

Introducing a product sustainability budget at an automotive company—one option to increase the use of LCSA results in decision-making processes Abstract Purpose Product sustainability assessment should evaluate the impacts on all three dimensions of sustainability (environment, economy, and society). Life cycle sustainability assessment (LCSA) is a framework that extends life cycle-based product assessment to all three dimensions. Evaluation of trade-off situations poses a challenge within LCSA in a business context, especially if improvement measures for product sustainability lead to higher costs. This paper introduces the concept of the Product Sustainability Budget (PSB) to enable a decision for improvement measures despite of rising costs. It demonstrates a way to create such a PSB and how to combine it with an operationalized LCSA framework at an automotive company. Methods A survey was carried out asking 250 potential customers of the premium car segment in Germany via Choice-Based-Conjoint-Analysis (CBCA) about their preference of a sustainability interior package in a car. The sustainability package was one of the three specifications of a potential car interior (standard, luxury, sustainability) and was asked along four other attributes (price, drive train, engine power, and consumption). The survey was expanded by an Advanced-Van-Westendorp analysis to ask respondents about their willingness-to-pay (WTP) for such a package. The major findings of the study (take rate and price for the sustainability interior package) were then implemented in a business case logic from which the PSB was created. Results and discussion Nineteen percent of the entire sample would prefer the sustainability interior package to the other packages (=potential take rate) while the rest (81%) favored the luxury package. The package should be sold to this (potential) target group at price premium of 1.3–1.7% for a middle class limousine (or 0.4–1.1% when corrected for overstated WTP). It could be shown in a theoretical business case logic for such a sustainability package that the profit could be converted to form the PSB, which could compensate an increase in costs caused by a measure to improve product sustainability. The PSB opened up a solution space to identify the ideal set out of several possible improvement measures. Conclusions The introduction of an LCSA evaluation scheme on component level in combination with the proposed Product Sustainability Budget could enable substantial product sustainability improvement even when costs increase. The combination of an implicit CBCA and an explicit WTP study delivered a sound basis for creating this Product Sustainability Budget. The proposed concept should be applied in a business context to test its viability and additionally investigate customers’ WTP for improved social impacts.

Environmental improvement of lead refining: a case study of water footprint assessment in Jiangxi Province, China Abstract Purpose China is currently facing water scarcity due to its large national population and rapid economic development. Lead is a typical non-ferrous metal. The lead industry is one of the top 10 water-consuming industries in China and suffers from the heavy burden of properly managing discharged wastewater containing heavy metals and organic pollutants. Accordingly, a water footprint analysis of lead refining was conducted in this study to enhance the water management in China’s lead industry. This study is part 2 of the environmental improvement for lead-refining series. Methods In accordance with the ISO 14046 standard, life cycle assessment-based water footprint analysis was applied to a lead-refining enterprise in Jiangxi Province, China. Five midpoint (i.e., water scarcity, aquatic eutrophication, carcinogens, non-carcinogens, and freshwater ecotoxicity) and two endpoint (i.e., human health and ecosystem quality) indicators are utilized to assess the water footprint impact results. Results and discussion Direct pollutant emissions are a major contributor to ecosystem quality and freshwater ecotoxicity, whereas indirect processes (i.e., industrial hazardous waste landfill, transport, and chemicals) contribute considerably to human health, aquatic eutrophication, and carcinogen categories. Chromium, copper, arsenic, and zinc were the key substances in the lead production chain, and their emissions exerted a significant impact on human health and ecosystem quality. Conclusions Reducing direct copper emission was the most important key to minimizing ecosystem quality decline in China’s lead industry, and optimizing indirect processes was effective in mitigating the impact on human health. Enhancing wastewater treatment, increasing chemical consumption efficiency, optimizing transport and industrial hazardous waste disposal, improving supervision, issuing relevant governmental regulations, and adopting advanced wastewater treatment technologies are urgently needed to control the water footprint.

Environmental impacts of a highly congested section of the Pan-American highway in Peru using life cycle assessment Abstract Purpose Road construction and transportation generate significant environmental impacts. Hence, it is increasingly important to understand the environmental burdens produced throughout the different stages of road development: construction, maintenance, traffic, and end-of-life. In this study, life cycle assessment (LCA) was used as an environmental management methodology to determine the impacts associated with a 22.4 km stretch of the South Pan-American (PS) highway in the province of Lima, Peru, one of the main access routes for traffic and goods entering Lima, located in a hyper-arid area parallel to the Pacific Ocean. Methods Life cycle modeling included the site-specific estimation of particulate matter emissions due to tire abrasion, brake lining, and road surface dust. In addition, different modeling options for combustion emissions for vehicles were considered. For this, sensitivity and uncertainty analysis were undertaken considering different emission standards and current vehicle fleet characteristics. The impact assessment stage included the calculation of climate change emissions, as well as air quality and abiotic depletion impact categories. Results and discussion Results demonstrate that environmental impacts are mainly attributable to traffic, representing in all impact categories assessed over 97% of burdens. The sensitivity analysis suggests that the use of secondary data from commonly used life cycle databases is a good proxy for the estimation of global warming potential impacts in the transport sector. However, for air quality categories, important variability was detected based on modeling assumptions. Conclusions This study intends to serve as a reference for the life cycle modeling of controlled access highways in developing countries, particularly in hyper-arid or desert areas.

Assessing variability in carbon footprint throughout the food supply chain: a case study of Valencian oranges Abstract Purpose This study aims to analyse the variability in the carbon footprint (CF) of organically and conventionally produced Valencian oranges (Spain), including both farming and post-harvest (PH) stages. At the same time, two issues regarding sample representativeness are addressed: how to determine confidence intervals from small samples and how to calculate the aggregated mean CF (and its variability) when the inventory is derived from different sources. Methods The functional unit was 1 kg of oranges at a European distribution centre. Farming data come from a survey of two samples of organic and conventional farms; PH data come from one PH centre; and data on exportation to the main European markets were obtained from official secondary sources. To assess the variability of the farming subsystem, a bootstrap of the mean CF was performed. The variability of the PH subsystem was assessed through a Monte Carlo simulation and a subsequent subsampling bootstrap. A weighted discrete distribution of the CF of distribution and end-of-life (EoL) was built, which was also bootstrapped. The empirical distribution of the overall CF was obtained by summing all iterations of the three bootstrap procedures of the subsystems. Results and discussion The CF of the baseline scenarios for conventional and organic production were 0.82 and 0.67 kg CO2 equivalent·kg orange−1, respectively; the difference between their values was due mainly to differences in the farming subsystem. Distribution and EoL was the subsystem contributing the most to the CF (59.3 and 75.7% of the total CF for conventional and organic oranges, respectively), followed by the farming subsystem (34.1 and 19.8% for conventional and organic oranges, respectively). The confidence intervals for the CF of oranges were 0.72–0.92 and 0.61–0.82 kg CO2 equivalent·kg orange−1 for conventional and organic oranges, respectively, and a significant difference was found between them. If organic production were to reach 50% of the total exported production, the CF would be reduced by 5.4–8.4%. Conclusions The case study and the methods used show that bootstrap techniques can help to test for the existence of significant differences and estimate confidence intervals of the mean CF. Furthermore, these techniques allow several CF sources to be combined so as to estimate the uncertainty in the mean CF estimate. Assessing the variability in the mean CF (or in other environmental impacts) gives a more reliable measure of the mean impact.

Pathway to domestic natural rubber production: a cradle-to-grave life cycle assessment of the first guayule automobile tire manufactured in the United States Abstract Purpose Guayule (Parthenium argentatum) is a perennial shrub that can be cultivated in the Southwestern US. It produces natural rubber that could be a viable substitute for Hevea natural rubber and synthetic rubbers currently used in tires. Drivers for producing domestic guayule rubber include fluctuations in price and availability of imported Hevea rubber. A tire was manufactured in 2017 where guayule rubber was substituted for all of the Hevea and synthetic rubber in the conventional tire. Methods Life cycle assessment (LCA) from cradle to grave was used to evaluate the environmental and energy sustainability of the guayule tire, and these metrics were benchmarked against those of the conventional tire (CT). Functional units of 1 kg natural rubber for agricultural processes, as well as 1 tire for the cradle-to-grave study were considered. Life cycle inventory (LCI) data were collected directly from primary sources, including guayule field experiments, a rubber-processing company, and a major tire manufacturer. Scenario analysis was used to evaluate alternative processes, such as irrigation options in guayule cultivation, processing scale in rubber extraction, and selection of allocation methodology in LCAs. Model uncertainty was characterized using Monte Carlo analysis. Results and discussion The LC energy consumption of the guayule tire (GT) was 13.7 GJ/tire (including co-product credits, excluding C sequestration during agriculture), compared to 16.4 GJ/tire for the CT. The GT had 6–30% lower emissions than CT in ten different environmental impact categories. Bagasse co-product in energy applications showed benefits of reducing energy consumption by 10% and decreasing environmental impacts by up to 11%. GT’s use-phase resulted in the highest energy consumption (95%) and environmental impacts ranging between 81 and 99%. Variables in use phase, i.e., rolling resistance coefficient, vehicle efficiency, and tire lifetime, and those in guayule cultivation i.e., rubber and biomass yields, were key model parameters. The effect of excluded but potentially important model parameters, i.e., guayule carbon sequestration and resin co-product were tested via sensitivity analyses. Conclusions Based on these results that factored in the lower rolling resistance coefficient of a guayule tire—a significant element that improves the fuel economy of an automobile—the guayule rubber tire shows promise in its ability to replace current conventional tires. The first commercially manufactured guayule rubber passenger tire will most likely substitute components, which are either partially or fully guayule, instead of guayule replacing 100% of the existing rubbers as shown in this study.

Life cycle assessment of run-of-river hydropower plants in the Peruvian Andes: a policy support perspective Abstract Purpose Low-carbon emissions are usually related to hydropower energy, making it an attractive option for nations with hydropower potential as it enables them to meet increasing electricity demand without relying on burning fossil fuels. In fact, the new wave of hydropower plant construction is occurring mainly in tropical areas where an additional environmental impact must be considered: biogenic greenhouse gas (GHG) emissions due to the degradation of biogenic carbon in reservoirs. Peru is planning to install up to 2000 MW in hydropower until 2021, but the input and output flows, as well as the environmental impacts that these generate, have not been explored. Hence, a set of three hydropower plants built in the past decade located in the Peruvian Andes were analyzed from a life cycle perspective. The main objective of the study is to generate detailed life cycle inventories for each of these three hydropower plants with the aim of obtaining specific information for current conditions in Peru. Methods The life cycle assessment methodology was applied to compute the environmental impacts. Data collection was based mainly on primary data obtained directly from the hydropower companies, although biogenic emissions were modeled considering local net primary productivity conditions and other site-specific conditions. Although the calculation of GHG emissions related to hydropower plants was a priority, considering the important policy implications of decarbonizing the Peruvian electricity grid, other environmental categories, such as eutrophication or the depletion of abiotic resources, were also considered. The IPCC method was used to calculate GHG emissions, whereas a set of eight additional impact categories were computed using the ReCiPe 2016 method. Results and discussion Results show that GHG emissions per unit of electricity generated were in the lower range of emissions observed in the literature, in all three cases below 3 g CO2eq/kWh. Biogenic emissions represented less than 5% of the total GHG emissions despite their location in a tropical nation, due to the arid conditions of the landscape in the Andean Highlands, as well as the mild temperatures that are present in the reservoirs. In terms of stratospheric ozone depletion, a GHG with ozone depletion properties, N2O, was the main source of impact. Conclusions The results are intended to be of utility for an array of applications, including relevance in decision-making in the energy sector and policy-making at a national level, considering the implications in terms of meeting the nationally determined contributions to mitigate climate change in the frame of the Treaty of Paris.

Environmental impact of evolving coffee technologies Abstract Purpose Coffee is a ubiquitous beverage in the USA today, accounting for 19% of the world’s coffee consumption. Although coffee consumption in itself is not new, the technology for brewing coffee and its corresponding environmental impact has been evolving rapidly in recent years, particularly with the widespread adoption of the single-serve coffee pod. This work utilizes a midpoint life cycle assessment with multiple environmental impact categories, to assess the environmental impact of a conventional (drip filter) brewing system, compared to a novel (single-serve coffee pod) brewing system, from cradle to grave. Methods This work analyzes the impact of consumer habits (such as leaving the novel system in standby mode) and phantom electricity consumption on the environmental impact of the system, in addition to the brewing systems themselves. The TRACI (Tool for Reduction and Assessment of Chemical and Other Environmental Impacts) suite is utilized to define the impact categories for the analysis, providing a holistic view. The SimaPro software tool is utilized along with multiple databases to enable the analysis. Results and discussion The question as to which coffee brewing system has the lowest environmental impact is a function of the phase, boundaries, and impact categories considered. The conventional brewing system has a lower environmental impact, with respect to raw materials and manufacturing. However, when only brewing is considered, the novel system has a lower environmental impact, suggesting that tradeoffs may occur. When the overall brewing system is considered throughout its lifetime, the system with the greatest environmental impact is not only a function of the technology, but also human behavior. The conventional system has a greater environmental impact than the novel system across some of the impact categories when phantom electricity usage is considered. However, when standby electricity consumption is considered, the novel system has the greater environmental impact due to the increased electricity consumption. Meaning that it is not only the technological aspects of the system that influence its environmental impact, but also how the technology is used. Conclusions A major conclusion of this work is that although the technology utilized to brew the coffee is relevant to the environmental impact, the human usage of the technology is also equally relevant, although it is not often the focus of literature in this area. In order to truly understand and quantify the environmental impact of brewing coffee across multiple technologies, more information about coffee consumption habits is needed.