Methodological review and detailed guidance for the life cycle interpretation phase

Rapid gram-scale microwave-assisted synthesis of organic anodes for sodium-ion batteries with environmental impact assessment

Development of sustainable synthesis methods of organic electrode materials (OEMs) for sodium (Na)-ion batteries must take hold rapidly in large scale-synthesis if subsequent commercialisation is to occur. We report a facile and rapid gram-scale synthesis method based on microwave irradiation for disodium naphthalene-2,6-dicarboxylate (Na-NDC) and mono/disodium benzene-1,4-dicarboxylate (Na-BDC) as model compounds. Phase purity and formation of materials was confirmed by various characterisation techniques. The electrochemical performance was tested in both half and full cell formats and compared to material obtained via smaller scale synthesis, revealing state-of-the art performance in terms of capacity retention and cyclability. The environmental impacts upon organic anode synthesis were quantified according to cradle-to-gate life cycle assessment (LCA). The results allow for the identification of environmental hotspots during production, indicating areas for future process optimisation. Interestingly, remarkably reduced impacts are obtained compared to conventional syntheses at milligram scale. Additionally, this work suggests potential significant improvements upon additional upscaling and solvent recycling.

Environmental Sustainability of Natural Biopolymer-Based Electrolytes for Lithium Ion Battery Applications

Biopolymer based electrolytes can overcome current performance limitations of lithium-ion batteries (LIBs). Biopolymers enable electrolytes with high ionic conductivities and wide electrochemical stability windows. While the biobased character of natural materials is claimed as an inherent advantage in meeting current environmental sustainability challenges, further research is required to quantify and compare their environmental impacts as electrolytes. The challenge is addressed by identifying the most promising biopolymer electrolytes for LIBs, measuring ionic conductivities and electrochemical stability windows, and quantifying environmental impacts using life cycle assessment. The environmental impacts of the cost to isolate cellulose derivatives, nanocelluloses, chitin/nanochitin, chitosan, lignin, agar, and silk are reported for climate change, acidification, freshwater ecotoxicity, marine eutrophication, human toxicity, and water use. Material criticality, circularity index, and material circularity indicator, emerging impact categories are prioritized to help integrate biopolymers into circular and sustainable materials. The electrochemical properties and environmental impacts of natural biopolymer membrane-liquid electrolyte pairs, gel electrolytes, and solid electrolytes are quantified and benchmarked against conventional fossil-based electrolytes, providing consistent and comparable electrochemical properties of the most relevant biopolymer electrolytes fabricated so far. This study highlights the significant functional and environmental benefits of biopolymer electrolytes and identifies the most electrochemically competitive biopolymer electrolytes in LIBs.

Additive inclusion in plastic life cycle assessments, part II: Review of additive inventory data trends and availability

Plastic additives are as essential as polymers to the production and performance of plastic materials. Additive content can vary in composition and functionality depending on the product, producer, application, and production method. Such variation may be a barrier to achieving high-quality recycling and planning for plastic circular economy futures. Yet, as found in Part I, although there is increasing awareness of the importance of additives in plastics, they are often poorly disclosed or only briefly discussed in life cycle assessments (LCAs). In part II, we focus on the inclusion of additives in plastic processes in the database most used in plastic LCAs to date (Ecoinvent) and find that additives have historically been omitted from plastic granulate data and in production processes in the evaluated database. Thus, many practitioners will need to separately include additives in their models of plastic life cycles. To support practitioners in this endeavor, we then assess the availability of the 13,587 additives identified in the recent UN Chemicals in Plastics Report across the three major LCI databases (CarbonMinds, Ecoinvent, and LCA for Experts [GaBi]). We find that databases currently cover only 1,209 of these additives. Moreover, we assert that transparency regarding additive inclusion in plastics datasets, availability of additive datasets, and additive data completeness are major barriers to additive inclusion in plastic LCAs. Thus, we recommend focusing on the development of additive datasets, and we provide a tool for the identification of additive dataset availability and data gaps to improve the quality of plastic LCAs.

Designing for Degradation: Transient Devices Enabled by (Nano)Cellulose

Transient technology involves materials and devices that undergo controlled degradation after a reliable operation period. This groundbreaking strategy offers significant advantages over conventional devices based on non-renewable materials by limiting environmental exposure to potentially hazardous components after disposal, and by increasing material circularity. As the most abundant naturally occurring polymer on Earth, cellulose is an attractive material for this purpose. Besides, (nano)celluloses are inherently biodegradable and have competitive mechanical, optical, thermal, and ionic conductivity properties that can be exploited to develop sustainable devices and avoid the end-of-life issues associated with conventional systems. Despite its potential, few efforts have been made to review current advances in cellulose-based transient technology. Therefore, this review catalogs the state-of-the-art developments in transient devices enabled by cellulosic materials. To provide a wide perspective, the various degradation mechanisms involved in cellulosic transient devices are introduced. The advanced capabilities of transient cellulosic systems in sensing, photonics, energy storage, electronics, and biomedicine are also highlighted. Current bottlenecks toward successful implementation are discussed, with material circularity and environmental impact metrics at the center. It is believed that this review will serve as a valuable resource for the proliferation of cellulose-based transient technology and its implementation into fully integrated, circular, and environmentally sustainable devices.

Review of methodological decisions in life cycle assessment (LCA) of biorefinery systems across feedstock categories

The application of life cycle assessment (LCA) to biorefineries is a necessary step to estimate their environmental sustainability. This review explores contemporary LCA biorefinery studies, across different feedstock categories, to understand approaches in dealing with key methodological decisions which arise, including system boundaries, consequential or attributional approach, allocation, inventory data, land use changes, product end-of-life (EOL), biogenic carbon storage, impact assessment and use of uncertainty analysis. From an initial collection of 81 studies, 59 were included within the final analysis, comprising 22 studies which involved dedicated feedstocks, 34 which involved residue feedstocks (including by-products and wastes), and a further 3 studies which involved multiple feedstocks derived from both dedicated and secondary sources. Many studies do not provide a comprehensive LCA assessment, often lacking detail on decisions taken, omitting key parts of the value chain, using generic data without uncertainty analyses, or omitting important impact categories. Only 28% of studies included some level of primary data, while 39% of studies did not undertake an uncertainty or sensitivity analysis. Just 8% of studies included data related to dLUC with a further 8% including iLUC, and only 14% of studies considering product end of life within their scope. The authors recommend more transparency in biorefinery LCA, with justification of key methodological decisions. A full value-chain approach should be adopted, to fully assess burdens and opportunities for biogenic carbon storage. We also propose a more prospective approach, taking into account future use of renewable energy sources, and opportunities for increasing circularity within bio-based value chains.

How does plastic compare with alternative materials in the packaging sector? A systematic review of LCA studies

In the recent years, packaging made of conventional plastics has been increasingly replaced by materials believed to be more sustainable. However, perceived sustainability must align with scientific assessments, such as life cycle assessments (LCAs). This review analysed 53 peer-reviewed studies published in the time range 2019-2023, aiming at understanding the state of the art in LCA about the environmental impacts of packaging by focusing on the comparison between plastics and alternative materials. The literature showed that consumer perceptions often differ from LCA findings and revealed that, frequently, conventional plastics are not the least environmentally friendly choice. Bioplastics typically show benefits only in the climate change and the fossil resource depletion impact categories. The heavy weight of glass turns out to affect its environmental performances with respect to the light plastics, with reuse being an essential strategy to lower the burdens. The comparison between plastics and metals is more balanced, leaning more towards plastics for food packaging. Similarly, paper resulted often preferable than plastics. Finally, for the other materials (i.e. wood and textiles), the picture is variable. To be competitive with plastics, the alternative materials require improvements like the optimisation of their production processes, their reuse and enhanced end-of-life options. At the same time, recycled polymers could boost the eco-performance of virgin plastics.

Waste LCA and the future

Life cycle assessment (LCA) models quantifying the environmental aspects of waste management have become an integral part of waste management decision-making over the last two decades and have provided ample knowledge on both environmental benefits and drawbacks in the way we handle waste. Waste management and LCA modelling of waste management systems will soon be challenged by profound changes necessary in our societies and sectors to meet sustainable development goals. Foreseen changes in energy, material, and nutrient provision will directly and indirectly affect waste management in terms of its operation and goals. This study reflects on anticipated changes in society and industrial sectors and how these changes may affect waste management and LCA modelling of waste management systems in terms of waste input, the modelling of technologies and systems and exchanges of energy, materials, and nutrients, as well as how it may affect impact assessment and the interpretation of results. The study provides practical recommendations for LCA modelling of future waste management systems, which will hopefully lead to robust assessments that can support decision-making in an evolving society subject to great changes.

Chitin-based pulps: Structure-property relationships and environmental sustainability

The deconstruction and valorization of chitinous biomass from crustaceans is a promising route for sustainable bioproduct development alternative to petroleum-based materials. However, chitin nanocrystal and chitin nanofibril isolation from crustacean shells is often subjected to extensive processing, compromising their environmental and cost sustainability. To address the sustainability challenge that chitin valorization presents, herein we introduce a mild fibrillation route to generate "chitin pulp"; where a careful control of the macro- and micro-fibrillated chitin with protein and mineral components yields tailored properties. Films produced from protein-rich chitin pulp showed ultimate strength of up to 93 ± 7 MPa. The surface energy and wetting behavior, going from hydrophilic to nearly-hydrophobic, could be tailored as a function of pulp composition. Life cycle assessment of the protein-rich chitin pulps demonstrated that the global warming potential of chitin pulp is reduced by 2 to 3 times when compared to chitin nanocrystals. Overall, this work presents a new and potentially scalable route for the generation of chitin-based materials having a reduced environmental footprint compared to nanochitins and chitosan, thus opening a new route for the valorization of chitin beyond nanochitin for the development of environmentally and economically sustainable materials.

From full life cycle assessment to simplified life cycle assessment: A generic methodology applied to sludge treatment

Life cycle assessment is widely used to evaluate sludge treatment methods. However, detailed life cycle assessment is time-consuming and resource-intensive. In addition, the complex characteristics of sludge and the variety of treatment methods increase the difficulty of sludge treatment life cycle assessment. There is an urgent need to develop simplified life cycle assessment models to allow rapid decision-making. This study proposes a simplified method of sludge treatment life cycle assessment based on logistic regression analysis. The simplified model relies on the total environmental impact and very few or even a single input parameters. Contribution and data quality analysis were introduced to identify key input parameters and to obtain model training data. The method was eventually applied to traditional sludge treatment methods, showing that it can quickly and accurately predict environmental impact. Representative analysis showed that the model would be affected by technology and energy structure modification. It is hoped that this study will provide a reference and new perspectives for a simplified life cycle assessment of sludge treatment.

Life Cycle Assessment in a Nutshell-Best Practices and Status Quo for the Plastic Sector

Life cycle assessment (LCA) is an internationally standardized methodology to evaluate the potential environmental impacts of products and technologies and assists in lowering their negative environmental consequences. So far, extensive knowledge of LCA-their application and interpretation-is restricted to experts. However, the importance of LCA is increasing due to its application in business, environmental, and policy decision-making processes. Therefore, general knowledge of LCA is critically important. The current work provides an introduction to LCA for non-experts discussing important steps and aspects and therefore can be used as a starting point for LCA. In addition, a comprehensive checklist for non-experts with important content and formal aspects of LCA is provided. Specific aspects of LCA for the plastics sector along the value chain are also discussed, including their limitations.

Assessment of building materials in the construction sector: A case study using life cycle assessment approach to achieve the circular economy

The construction sector plays a significant role in contributing to greenhouse gas (GHG) emissions, necessitating effective and practical solutions. This study addresses the underutilization of Life Cycle Assessment (LCA) in the construction sector and demonstrates its benefits as a decision-making tool for mitigating embodied carbon. The research focuses on a G+2 building in Dubai, UAE, conducting LCA during the construction phases to assess embodied carbon levels. Results indicate that the careful selection of construction materials and involvement of LCA at the early stages of construction resulted in a 26 % reduction in the building's embodied carbon. The study recognizes the limitations of LCA but emphasizes its value and recommends future research to enhance its coverage of sustainability aspects. The findings highlight the construction sector's potential to overcome anthropogenic challenges through green solutions. Policymakers' support is crucial for implementing strategies that reduce the construction industry's carbon footprint and embrace a circular economy. The study contributes to the literature by bridging the gap in understanding the application of LCA in construction decision-making. It emphasizes the importance of transitioning to sustainable practices and circularity in the construction sector. By using LCA as a tool, construction professionals can make informed choices to reduce embodied carbon. This study underscores the urgency for adopting greener practices in the construction sector, leading to a more sustainable and low-carbon future.

Evaluating impacts of paper and electronic billing and invoicing business systems from an environmental and energy perspective

The environmental and energy impacts of ICT were identified using a comparative life cycle assessment (CompLCA) focused on business invoicing processes comparing online to paper processes. There were net energy benefits from online billing. The potential impact across the economy and society is large, particularly as COVID-19 has forced many businesses and government services to shift to online service provision. For one million bills produced electronically and received by customers instead of a paper bill, 18.9 t CO2e is avoided, which translates to a national saving of 22,680 tCO2e, assuming 1.2 billion annual invoicing transactions. The impacts of CO2 are sensitive, however, to several assumptions. The study's originality was to show the range of invoicing variables that impact energy and the environment and to highlight which ones can be influenced. For example, the number of online bills produced was the most sensitive. However, the results are reversed under commonly occurring customer use situations. The study demonstrates the positive and negative impacts from the digitalisation of businesses. It suggests remedies based on the main drivers identified under company, contractor and customer control that led to energy consumption and environmental and land use impacts.

Bioplastic production in terms of life cycle assessment: A state-of-the-art review

The current transition to sustainability and the circular economy can be viewed as a socio-technical response to environmental impacts and the need to enhance the overall performance of the linear production and consumption paradigm. The concept of biowaste refineries as a feasible alternative to petroleum refineries has gained popularity. Biowaste has become an important raw material source for developing bioproducts and biofuels. Therefore, effective environmental biowaste management systems for the production of bioproducts and biofuels are crucial and can be employed as pillars of a circular economy. Bioplastics, typically plastics manufactured from bio-based polymers, stand to contribute to more sustainable commercial plastic life cycles as part of a circular economy in which virgin polymers are made from renewable or recycled raw materials. Various frameworks and strategies are utilized to model and illustrate additional patterns in fossil fuel and bioplastic feedstock prices for various governments' long-term policies. This review paper highlights the harmful impacts of fossil-based plastic on the environment and human health, as well as the mass need for eco-friendly alternatives such as biodegradable bioplastics. Utilizing new types of bioplastics derived from renewable resources (e.g., biowastes, agricultural wastes, or microalgae) and choosing the appropriate end-of-life option (e.g., anaerobic digestion) may be the right direction to ensure the sustainability of bioplastic production. Clear regulation and financial incentives are still required to scale from niche polymers to large-scale bioplastic market applications with a truly sustainable impact.

Integrated crop-livestock-bioenergy system brings co-benefits and trade-offs in mitigating the environmental impacts of Chinese agriculture

Agricultural bioenergy utilization relies on crop and livestock production, favouring an integrated crop-livestock-bioenergy production model. Yet the integrated system's exact contribution to mitigating various environmental burdens from the crop production system and livestock production system remains unclear. Here we inventory the environmental impacts of each process in three subsystems at both national and regional scales in China, ultimately identifying key processes and impact categories. The co-benefits and trade-offs in nine impact categories are investigated by comparing the life cycle impacts in the background scenario (crop production system + livestock production system) and foreground scenario (integrated system). Freshwater eutrophication is the most serious impact category in both scenarios. Except terrestrial acidification, the mitigation effects on the other eight impact categories vary from 1.8% to 94.8%, attributed to fossil energy and chemical fertilizer offsets. Environmental trade-offs should be deliberated when expanding bioenergy utilization in the identified critical regions.

Systematic Literature Review on Dynamic Life Cycle Inventory: Towards Industry 4.0 Applications

Life cycle assessment (LCA) is a well-established methodology to quantify the environmental impacts of products, processes, and services. An advanced branch of this methodology, dynamic LCA, is increasingly used to reflect the variation in such potential impacts over time. The most common form of dynamic LCA focuses on the dynamism of the life cycle inventory (LCI) phase, which can be enabled by digital models or sensors for a continuous data collection. We adopt a systematic literature review with the aim to support practitioners looking to apply dynamic LCI, particularly in Industry 4.0 applications. We select 67 publications related to dynamic LCI studies to analyze their goal and scope phase and how the dynamic element is integrated in the studies. We describe and discuss methods and applications for dynamic LCI, particularly those involving continuous data collection. Electricity consumption and/or electricity technology mixes are the most used dynamic components in the LCI, with 39 publications in total. This interest can be explained by variability over time and the relevance of electricity consumption as a driver of environmental impacts. Finally, we highlight eight research gaps that, when successfully addressed, could benefit the diffusion and development of sound dynamic LCI studies.

The Cradle-to-Cradle Life Cycle Assessment of Polyethylene terephthalate: Environmental Perspective

Over the last several years, the number of concepts and technologies enabling the production of environmentally friendly products (including materials, consumables, and services) has expanded. One of these ways is cradle-to-cradle (C2C) certified^TM. Life cycle assessment (LCA) technique is used to highlight the advantages of C2C and recycling as a method for reducing plastic pollution and fossil depletion by indicating the research limitations and gaps from an environmental perspective. Also, it estimates the resources requirements and focuses on sound products and processes. The C2C life cycle measurements for petroleum-based poly (ethylene terephthalate) (PET) bottles, with an emphasis on different end-of-life options for recycling, were taken for mainland China, in brief. It is considered that the product is manufactured through the extraction of crude oil into ethylene glycol and terephthalic acid. The CML analysis method was used in the LCIA for the selected midpoint impact categories. LCA of the product has shown a drastic aftermath in terms of environmental impacts and energy use. But the estimation of these consequences is always dependent on the system and boundary conditions that were evaluated throughout the study. The impacts that burden the environment are with the extraction of raw material, resin, and final product production. Minor influences occurred due to the waste recycling process. This suggests that waste degradation is the key process to reduce the environmental impacts of the production systems. Lowering a product’s environmental impact can be accomplished in a number of ways, including reducing the amount of materials used or choosing materials with a minimal environmental impact during manufacture processes.

Life cycle assessment of plant cell cultures

A novel food such as plant cell culture (PCC) is an important complementary asset for traditional agriculture to tackle global food insecurity. To evaluate environmental impacts of PCC, a life cycle assessment was applied to tobacco bright yellow-2 and cloudberry PCCs. Global warming potential (GWP), freshwater eutrophication potential (FEUP), marine eutrophication potential, terrestrial acidification potential (TAP), stratospheric ozone depletion, water consumption and land use were assessed. The results showed particularly high contributions (82-93%) of electricity consumption to GWP, FEUP and TAP. Sensitivity analysis indicated that using wind energy instead of the average Finnish electricity mix reduced the environmental impacts by 34-81%. Enhancement in the energy efficiency of bioreactor mixing processes and reduction in cultivation time also effectively improved the environmental performance (4-47% reduction of impacts). In comparison with other novel foods, the environmental impacts of the PCC products studied were mostly comparable to those of microalgae products but higher than those of microbial protein products produced by autotrophic hydrogen-oxidizing bacteria. Assayed fresh PCC products were similar or close to GWP of conventionally grown food products and, with technological advancements, can be highly competitive.

Teaching life cycle assessment in higher education

PURPOSE

Scientific Life Cycle Assessment (LCA) literature provides some examples of LCA teaching in higher education, but not a structured overview of LCA teaching contents and related competencies. Hence this paper aims at assessing and highlighting trends in LCA learning outcomes, teaching approaches and developed content used to equip graduates for their future professional practices in sustainability.

METHODS

Based on a literature review on teaching LCA in higher education and a collaborative consensus building approach through expert group panel discussions, an overview of LCA learning and competency levels with related teaching contents and corresponding workload is developed. The levels are built on the European Credit Transfer and Accumulation System (ECTS) and Bloom's taxonomy of learning.

RESULTS AND DISCUSSION

The paper frames five LCA learning and competency levels that differ in terms of study program integration, workload, cognitive domain categories, learning outcomes, and envisioned professional skills. It furthermore provides insights into teaching approaches and content, including software use, related to these levels.

CONCLUSIONS AND RECOMMENDATIONS

This paper encourages and supports higher educational bodies to implement a minimum of 'life cycle literacy' into students' curriculum across various domains by increasing the availability, visibility and quality of their teaching on life cycle thinking and LCA.