Review Of Life Cycle Assessment Research Articles

Critical Review of Life Cycle Assessment of Hydrogen Production Pathways

In light of growing concerns regarding greenhouse gas emissions and the increasingly severe impacts of climate change, the global situation demands immediate action to transition towards sustainable energy solutions. In this sense, hydrogen could play a fundamental role in the energy transition, offering a potential clean and versatile energy carrier. This paper reviews the recent results of Life Cycle Assessment studies of different hydrogen production pathways, which are trying to define the routes that can guarantee the least environmental burdens. Steam methane reforming was considered as the benchmark for Global Warming Potential, with an average emission of 11 kgCO2eq/kgH2. Hydrogen produced from water electrolysis powered by renewable energy (green H2) or nuclear energy (pink H2) showed the average lowest impacts, with mean values of 2.02 kgCO2eq/kgH2 and 0.41 kgCO2eq/kgH2, respectively. The use of grid electricity to power the electrolyzer (yellow H2) raised the mean carbon footprint up to 17.2 kgCO2eq/kgH2, with a peak of 41.4 kgCO2eq/kgH2 in the case of countries with low renewable energy production. Waste pyrolysis and/or gasification presented average emissions three times higher than steam methane reforming, while the recourse to residual biomass and biowaste significantly lowered greenhouse gas emissions. The acidification potential presents comparable results for all the technologies studied, except for biomass gasification which showed significantly higher and more scattered values. Regarding the abiotic depletion potential (mineral), the main issue is the lack of an established recycling strategy, especially for electrolysis technologies that hamper the inclusion of the End of Life stage in LCA computation. Whenever data were available, hotspots for each hydrogen production process were identified.

Comparison of mass timber structure and RC structure with regard to sustainability by life cycle assessment

Since the 18th-century Industrial Revolution, high-rise have played a crucial role in addressing urbanization challenges, remaining a primary solution for urban living. However, this architectural advancement has also contributed to environmental decline. Presently, steel and concrete stand out as the predominant materials for high-rise construction, with well-documented significant carbon emissions. This paper delves into the potential of timber as an environmentally friendly alternative in high-rise construction to address such environmental concerns. Furthermore, it examines the impact of these structures on land load. The paper conducts a comprehensive review of life cycle assessment (LCA) studies and offers a comparative analysis of the climate change impacts associated with timber versus conventional materials like reinforced concrete (RC), underscoring the urgent need for sustainable development in the vertical expansion of our cities. The findings demonstrate that both the mass and carbon emissions of high-rise timber structures, in comparison to RC structures, can be reduced by approximately half. The paper aims to underscore the benefits of timber in comparison to conventional reinforced concrete methods, thereby informing material selection in favor of sustainable urban development.

A Review of Life Cycle Assessment of Soil Remediation Technology: Method Applications and Technological Characteristics

A Review of Life Cycle Assessment of Soil Remediation Technology: Method Applications and Technological Characteristics

Use of life cycle assessment (LCA) to advance optimisation of radiological protection and safety

Life cycle assessment (LCA) is a modelling technique used to determine the cradle-to-grave environmental and human health impacts from the production of a good or the provision of a service. Radiological protection may benefit from employing tools like LCA to obtain a broader perspective and enable comparison with analyses of non-radiological systems. Despite structural similarities to other well-established decision-aiding techniques (DATs), the impact assessment within LCA (i.e. LCIA) is not commonly used in the optimisation of radiological protection process. This paper provides a brief review of LCA, including LCIA, along with more traditional DATs (such as multi-attribute utility analysis) used in the optimisation process for comparison. Basic concrete shielding was considered as a simple, illustrative example; concrete attenuates emissions from a radiation source but is also associated with a financial cost as well as costs with respect to energy, material, and water use. LCA offers quantification of these and other key resources (termed ‘impact categories’). Ultimately, we offer that, depending on the circumstance, LCA can be a useful tool in radiological protection decision-making, complementing existing techniques.

Vegans, vegetarians, fish-eaters and meat-eaters in the UK show discrepant environmental impacts

Modelled dietary scenarios often fail to reflect true dietary practice and do not account for variation in the environmental burden of food due to sourcing and production methods. Here we link dietary data from a sample of 55,504 vegans, vegetarians, fish-eaters and meat-eaters with food-level data on greenhouse gas emissions, land use, water use, eutrophication risk and potential biodiversity loss from a review of 570 life-cycle assessments covering more than 38,000 farms in 119 countries. Our results include the variation in food production and sourcing that is observed in the review of life-cycle assessments. All environmental indicators showed a positive association with amounts of animal-based food consumed. Dietary impacts of vegans were 25.1% (95% uncertainty interval, 15.1–37.0%) of high meat-eaters (≥100 g total meat consumed per day) for greenhouse gas emissions, 25.1% (7.1–44.5%) for land use, 46.4% (21.0–81.0%) for water use, 27.0% (19.4–40.4%) for eutrophication and 34.3% (12.0–65.3%) for biodiversity. At least 30% differences were found between low and high meat-eaters for most indicators. Despite substantial variation due to where and how food is produced, the relationship between environmental impact and animal-based food consumption is clear and should prompt the reduction of the latter.

Sustainable Power Grid Expansion: Life Cycle Assessment, Modeling Approaches, Challenges, and Opportunities

Electric demand is steadily increasing, hence requiring continuous investments in modernizing, and expanding power grids worldwide. Traditionally, power system planning projects have considered minimizing the costs of capacity expansion and minimizing the amount of energy not served as the main objectives. With climate change policies enforcing the decommissioning of fossil-fuel-based generation, new clean and renewable generation technologies are being considered for power system capacity expansion projects. However, the environmental impacts of energy resources are not limited to carbon emissions and their contribution to global warming. In fact, every power generation technology can result in undesired impacts during its entire life cycle, which could negatively affect air quality, water resources, material resources, and/or human health. This paper provides an overview of how to assess the sustainability of power systems and power generation technologies based on life cycle assessment (LCA). A review of LCA, as applied to power systems and generation technologies, is presented with a discussion of general findings, challenges, and limitations. A review of the literature is then provided related to how sustainability objectives are currently incorporated in power grid design and capacity expansion models. Finally, shortcomings of the current models are discussed, along with opportunities for future research.

A Review of Life Cycle Assessment of Water Efficient Technologies in Buildings

A Review of Life Cycle Assessment of Water Efficient Technologies in Buildings

Review of life cycle assessments (LCA) for mobility powertrains

Continued economic growth is accelerating the demand for transport energy in the road, aviation, and marine sectors. The environmental impacts of technologies across these sectors need significant attention if society is to meet its climate change mitigation targets. Current policies focusing entirely on electrification are shown to be insufficient in mitigating environmental impacts. Powertrains equipped with combustion engines will still be operational 2040 onwards, especially in the developing countries and currently underdeveloped countries. In addition, the environmental impacts of electrified systems are not negligible, and lifecycle environmental impacts need attention. This paper presents a detailed summary of fuel-powertrain options that society will be dependent on, for next several decades. Environmental impacts using lifecycle assessment (LCA) are presented for various technologies. This review highlights the current inadequacies in application of LCA methods for transport systems, and the need to improve LCA methodologies to drive effective policy and decision making.

Review of Life Cycle Assessments for Steel and Environmental Analysis of Future Steel Production Scenarios

The steel industry is focused on reducing its environmental impact. Using the life cycle assessment (LCA) methodology, the impacts of the primary steel production via the blast furnace route and the scrap-based secondary steel production via the EAF route are assessed. In order to achieve environmentally friendly steel production, breakthrough technologies have to be implemented. With a shift from primary to secondary steel production, the increasing steel demand is not met due to insufficient scrap availability. In this paper, special focus is given on recycling methodologies for metals and steel. The decarbonization of the steel industry requires a shift from a coal-based metallurgy towards a hydrogen and electricity-based metallurgy. Interim scenarios like the injection of hydrogen and the use of pre-reduced iron ores in a blast furnace can already reduce the greenhouse gas (GHG) emissions up to 200 kg CO2/t hot metal. Direct reduction plants combined with electrical melting units/furnaces offer the opportunity to minimize GHG emissions. The results presented give guidance to the steel industry and policy makers on how much renewable electric energy is required for the decarbonization of the steel industry.

Critical review of life cycle assessment of lithium-ion batteries for electric vehicles: A lifespan perspective

Lithium-ion batteries (LIBs) are the ideal energy storage device for electric vehicles, and their environmental, economic, and resource risks assessment are urgent issues. Therefore, the life cycle assessment (LCA) of LIBs in the entire lifespan is becoming a hotspot. This study first reviews the basic framework and types, standards and methods, and technical challenges of LCA. Then, the cradle-to-cradle LCA framework for LIBs is constructed, and the technical route of LCA in the stages of battery production, usage, secondary utilization, and material recycling are analyzed in detail. Finally, the carbon footprint in the battery production and recycling stages is conducted under the current and future energy mixes. The results show that battery production significantly impacts the environment and resources, and battery materials recycling and remanufacturing present considerable environmental and economic values. Moreover, the greening of electricity is critical to reducing carbon emissions during the battery life cycle. • The framework, methods, and technical challenges of LCA are comprehensively reviewed. • The cradle-to-cradle LCA framework for lithium-ion batteries is constructed. • Carbon emissions during battery production and recycling are analyzed. • Carbon emissions during battery production under different energy mixes are investigated.

A Content Review of Life Cycle Assessment of Nanomaterials: Current Practices, Challenges, and Future Prospects.

This paper provides a comprehensive review of 71 previous studies on the life cycle assessment (LCA) of nanomaterials (NMs) from 2001 to 2020 (19 years). Although various studies have been carried out to assess the efficiency and potential of wastes for nanotechnology, little attention has been paid to conducting a comprehensive analysis related to the environmental performance and hotspot of NMs, based on LCA methodology. Therefore, this paper highlights and discusses LCA methodology’s basis (goal and scope definition, system boundary, life cycle inventory, life cycle impact assessment, and interpretation) to insights into current practices, limitations, progress, and challenges of LCA application NMs. We found that there is still a lack of comprehensive LCA study on the environmental impacts of NMs until end-of-life stages, thereby potentially supporting misleading conclusions, in most of the previous studies reviewed. For a comprehensive evaluation of LCA of NMs, we recommend that future studies should: (1) report more detailed and transparent LCI data within NMs LCA studies; (2) consider the environmental impacts and potential risks of NMs within their whole life cycle; (3) adopt a transparent and prudent characterization model; and (4) include toxicity, uncertainty, and sensitivity assessments to analyze the exposure pathways of NMs further. Future recommendations towards improvement and harmonization of methodological for future research directions were discussed and provided. This study’s findings redound to future research in the field of LCA NMs specifically, considering that the release of NMs into the environment is yet to be explored due to limited understanding of the mechanisms and pathways involved.

A human-centered review of life cycle assessments of bioplastics

A human-centered review of life cycle assessments of bioplastics

Operating in a Climate Crisis: A State-of-the-Science Review of Life Cycle Assessment within Surgical and Anesthetic Care.

Background:Both human health and the health systems we depend on are increasingly threatened by a range of environmental crises, including climate change. Paradoxically, health care provision is a significant driver of environmental pollution, with surgical and anesthetic services among the most resource-intensive components of the health system.Objectives:This analysis aimed to summarize the state of life cycle assessment (LCA) practice as applied to surgical and anesthetic care via review of extant literature assessing environmental impacts of related services, procedures, equipment, and pharmaceuticals.Methods:A state-of-the-science review was undertaken following a registered protocol and a standardized, LCA-specific reporting framework. Three bibliographic databases (Scopus®, PubMed, and Embase®) and the gray literature were searched. Inclusion criteria were applied, eligible entries critically appraised, and key methodological data and results extracted.Results:From 1,316 identified records, 44 studies were eligible for inclusion. The annual climate impact of operating surgical suites ranged between 3,200,000 and . The climate impact of individual surgical procedures varied considerably, with estimates ranging from . Anesthetic gases; single-use equipment; and heating, ventilation, and air conditioning system operation were the main emissions hot spots identified among operating room- and procedure-specific analyses. Single-use equipment used in surgical settings was generally more harmful than equivalent reusable items across a range of environmental parameters. Life cycle inventories have been assembled and associated climate impacts calculated for three anesthetic gases () and 20 injectable anesthetic drugs (). Discussion:Despite the recent proliferation of surgical and anesthesiology-related LCAs, extant studies address a miniscule fraction of the numerous services, procedures, and products available today. Methodological heterogeneity, external validity, and a lack of background life cycle inventory data related to many essential surgical and anesthetic inputs are key limitations of the current evidence base. This review provides an indication of the spectrum of environmental impacts associated with surgical and anesthetic care at various scales. https://doi.org/10.1289/EHP8666

Systematic Review of Life Cycle Assessment and Life Cycle Cost Analysis for Pavement and a Case Study

Development of the pavement network systems, which is inevitable due to the rapid economic growth, has increasingly become a topic of significant concern because of the severe environmental impacts of road expansion. For achieving the sustainable development goals (SDGs), the policies and actions towards the pavements’ life cycle assessment (LCA) and life cycle cost analysis (LCCA) must be carefully assessed. Consequently, the purpose of this review is to present an overview of LCA and LCCA used in pavement engineering and management. Through the quality control of PRISMA, fifty-five most relevant documents were extracted for a thorough investigation. The state of the art review reveals that a limited number of the papers considered environmental impacts of the pavements. Consequently, to assess the environmental impact cost, a conceptual framework was developed to better consider the LCA and LCCA on various aspects of the pavement projects including the sustainability aspects. Besides, a case study was given to validate the literature review towards proposing a novel framework for the incorporation of environmental impact cost.

Dual closed-loop chemical recycling support sustainable mitigation of plastic pollution

Recently, the Feringa Nobel Prize Scientist Joint Research Center demonstrated a green method to synthesize plastics from natural small thioctic acid (TA) monomers. This novel recycling system provides successful chemical recycling using a dual closed-loop process under mild operating conditions. Here, we discuss the critical environmental sustainability dynamics of these recycling systems and their potential to support a plastic circular economy.

Status of Life Cycle Assessment (LCA) in Africa

Life cycle assessment (LCA) has received attention as a tool to evaluate the environmental impacts of products and services. In the last 20 years, research on the topic has increased, and now more than 25,000 articles are related to LCA in scientific journals databases such as the Scopus database; however, the concept is relatively new in Africa, where the number of networks has been highlighted to be very low when compared to the other regions. This paper focuses on a review of life cycle assessments conducted in Africa over the last 20 years. It aims at highlighting the current research gap for African LCA. A total of 199 papers were found for the whole continent; this number is lower than that for both Japan and Germany (more than 400 articles each) and nearly equal to developing countries such as Thailand. Agriculture is the sector which received the most attention, representing 53 articles, followed by electricity and energy (60 articles for the two sectors). South Africa (43), Egypt (23), and Tunisia (19) were the countries where most of the research was conducted. Even if the number of articles related to LCA have increased in recent years, many steps still remain. For example, establishing a specific life cycle inventory (LCI) database for African countries or a targeted ideal life cycle impact assessment (LCIA) method. Several African key sectors could also be assessed further.

Production of HMF, FDCA and their derived products: a review of life cycle assessment (LCA) and techno-economic analysis (TEA) studies

This review article summarises and discusses methodological and chemical aspects of LCA and TEA studies of HMF, FDCA and their derived products.

Wooden and Plastic Pallets: A Review of Life Cycle Assessment (LCA) Studies

Pallets are the tiny cogs in the machine that drive transportation in the global economy. The profusion of pallets in today’s supply chain warrants the investigation and discussion of their respective environmental impacts. This paper reviews the life cycle assessment studies analyzing the environmental impacts of pallets with the intent of providing insights into the methodological choices made, as well as compiling the inventory data from the studies reviewed. The study is a meta-analysis of eleven scientific articles, two conference articles, two peer-reviewed reports, and one thesis. The review was implemented to identify the key methodological choices made in those studies, such as their goals, functional units, system boundaries, inventory data, life cycle impact assessment (LCIA) procedures, and results. The 16 studies reviewed cumulatively analyzed 43 pallets. Mostly pooled (n = 22/43), block-type (n = 13/43), and wooden (n = 32/43) pallets with dimensions of 1219 mm × 1016 mm or 48 in. × 40 in. (n = 15/43) were studied. Most of the studies represented pallet markets in the United States (n = 9/16). Load-based (e.g., 1000 kg of products delivered), trip-based (e.g., 1000 trips), and pallet-based (e.g., one pallet) functional units were declared. A trip-based functional unit seems the most appropriate for accounting of the function of the pallets, as its purpose is to carry goods and facilitate the transportation of cargo. A significant amount of primary inventory data on the production and repair of wooden and plastic pallets are available, yet there are significant variations in the data. Data on pallets made of wood–polymer composites was largely missing.

Life cycle environmental impacts of wind energy technologies: A review of simplified models and harmonization of the results

Nowadays, wind energy is taking on primary role within renewable energies scenario. However, impact of wind energy industry on the environment still requires to be fully understood and better quantified. This study provides an updated review of Life Cycle Assessment (LCA) studies of electricity produced from onshore and offshore wind turbines (WTs). Special emphasis is put on results harmonization and simplified LCA models existing in the literature. The synthesis of the results is performed for wide range of WTs capacities, providing an exhaustive and general frame of the environmental impacts of WTs systems. Moreover, new simplified LCA models, which make use of a non-linear regression, were developed in this work for the following impact categories: Acidification Potential (AP), Eutrophication Potential (EP), Global Warming Potential (GWP) and Cumulative Energy Demand (CED) and for onshore (1–5000 kW) and offshore (500–8000 kW) WTs. Nonlinear data fitting models are provided with a sufficiently high correlation coefficient for total life cycle impacts. Moreover, the proposed simplified LCA models predict the final results with acceptable uncertainty. This indicates that the one-term power series describes the behavior of the impact indicators accurately, providing a useful correlation to estimate the life cycle environmental performance for a specific turbine model with a given nominal power. Furthermore, obtained simplified LCA models were generalized for different site-specific wind conditions, i.e. wind speeds and wind classes. By analyzing all the considered impact indicators for electricity generation, we notice that the highest values of life cycle impacts of electricity, for a particular WT correspond to the highest wind velocities. This is particularly valid for low nominal power turbines, which seem to be significantly affected by wind conditions. The trends exhibit an asymptotic behavior, indicating that, on the contrary, wind conditions are a minor contributor to the environmental impact of large-scale systems.

A review of life cycle assessment of recycled aggregate concrete

Abstract Recycled aggregate has emerged expecting to address raw materials shortage in construction sector by converting waste concrete into resource. Many researchers adopted life cycle assessment (LCA) to evaluate and compare environmental impact of recycled aggregate concrete (RAC) and natural aggregate concrete (NAC). However, there are numbers of problems in applying the LCA in RAC, a unified treatment of the subject is still lacking. By reviewing existing corresponding literature, this paper identified the existing problems of applying the LCA method in RAC from 5 aspects, including mixture design method, selection of functional units, allocation of inventory, CO2 uptake during the life cycle of concrete and transport distance of recycled aggregate. Review results indicate that when analyzing the environmental impact of RAC by LCA, a clear indication of the mixture design methods of RAC should be given at first. Second, a benchmark method to define the functional unit of the LCA of RAC is urgently needed to make different LCA studies comparable. A method that combining the effect of quality, mass and market price on the allocation procedure of recycled aggregate should be further investigated. Besides, ignoring CO2 uptake in the use stage of RAC will lead to an overestimated CO2 emission of RAC. In addition, a critical distance for recycled aggregate is existed when comparing the environmental impact between NAC and RAC. At last, some contents of recycled aggregate concrete for further research have been proposed.