Fuel cells have the potential to reduce greenhouse gas (GHG) emissions from deep-sea shipping. To fully understand the environmental impacts of integrating fuel cells into deep-sea ships, this study evaluates the life cycle environmental impacts from 2020 to 2050 for two leading fuel cell systems: liquid hydrogen with proton exchange membrane fuel cells (liquid-H₂ PEMFC) and liquid ammonia with solid oxide fuel cells (liquid-NH₃ SOFC). The study covers various factors, including changes in cargo capacity, operation modes, developments in hydrogen production and electricity decarbonization. We examine two energy scenarios developed by the International Energy Agency: the Stated Policies Scenario (STEPS) and the Net Zero Emissions by 2050 Scenario (NZE). Our findings reveal that, under different ranges and speeds, the liquid-H₂ PEMFC results in a 2% increase to a 10% decrease in cargo weight, while the liquid-NH₃ SOFC leads to a 4%–23% decrease. By 2050, under the NZE scenario, liquid-H₂ PEMFC and liquid-NH₃ SOFC can reduce GHG emissions per tonne-nautical mile by 69%–75% and 65%–71%, respectively, compared to traditional ships. The use of fuel cells also introduces environmental trade-offs. This assessment can help policymakers gain a more comprehensive understanding of the role of fuel cells in reducing GHG emissions in deep-sea shipping and underscores the potential environmental challenges associated with their large-scale deployment in the future.

Hydrogen-based fuels are potential candidates to help international shipping achieve net-zero greenhouse gas (GHG) emissions by around 2050. This paper quantifies the environmental impacts of liquid hydrogen, liquid ammonia, and methanol used in a Post-Panamax container ship from 2020 to 2050. It considers cargo capacity changes, electricity decarbonization, and hydrogen production transitions under two International Energy Agency scenarios: the Stated Policies Scenario (STEPS) and the Net Zero Emissions by 2050 Scenario (NZE). Results show that, compared to the existing HFO ship, hydrogen-based propulsion systems can decrease cargo weight capacity by 0.3 % to 25 %. In the NZE scenario, hydrogen-based fuels can reduce GHG emissions per tonne-nautical mile by 48 %–65 % compared to heavy fuel oil by 2050. Even with fully renewable hydrogen-based fuels, 18 %–31 % of GHG emissions would still remain. Using hydrogen-based fuels in internal combustion engines requires attention to minimize environmental trade-offs.

Environmentally extended multi-regional input–output (EEMRIO) analysis provides a robust methodology for assessing economic, social, and environmental footprints across nations and regions. Increasing its geographical resolution is essential for addressing local environmental issues and informing targeted policy decisions. While subnational EEMRIOs ideally rely on survey data, such data are often unavailable or resource-intensive to process. As a result, partitioners resort to proxies and algorithms. Yet, the transparency of these algorithms and the underlying data are often suboptimal. Here, we present a novel, open-source, top-down regionalization approach applicable to any EEMRIO database. Our method builds on location quotients (LQ), extending their application to a multi-regional framework. This extension ensures calculations remain traceable, eliminates the need for supplemental balancing procedures, and requires minimal, readily available additional proxy data, making it highly accessible for practitioners. Using European steel trade as a proof-of-concept, we demonstrate how this approach assesses local impacts, highlights local–global trade interactions, and identifies opportunities that national IO data often obscure.

The authors regret that the original version of this article contained numerical errors in Figure 2 within the main text and Table A1 of Appendix A. Supplementary data. Corrections that need to be made are presented as follows: • For Figure 2 in the main text, the label “0∼4mm SS (42.5%)” of a flow should be corrected to “0∼4mm SS (44.5%)”, as shown in Fig. C1 below. [Figure presented]• In Table A1 of Appendix A, the electricity usage for the “Wet processing” under the S1 BAU WP scenario should be corrected to “400 kWh” instead of “60,000 kWh”.The authors would like to apologise for any inconvenience caused and state that the changes reported do not affect the scientific results and conclusions of the manuscript.

The Basel Convention Plastic Waste Amendments, implemented in 2021, have the potential to reshape traditional ‘North-to-South' plastic waste trade patterns and their environmental impacts. We analyze plastic waste trade among 21 countries before (2019–2020) and after (2021–2022) the amendments, quantifying environmental impacts from transport and waste treatment using life cycle assessment. We find that post-amendment trade among selected EU and non-EU OECD countries increased to 71 %, up 12 percentage points from pre-amendment period, when half of the trade flowed to non-OECD Asian countries. This shift yielded modest increases of 2 % in climate and 5 % in energy benefits. Further expanding intra-EU-OECD trade could boost climate benefits by up to 12 %, mainly by reducing open burning in non-OECD Asian countries. These findings offer environmental insights into the EU's upcoming ban on plastic waste exports to non-OECD countries, suggesting future trade will likely concentrate among countries with aligned waste shipment rules.

The global trade of plastic waste has raised environmental concerns, especially regarding pollution in waste-importing countries. However, the overall environmental contribution remains unclear due to uncertain treatment shares between handling plastic waste abroad and domestically. Here, we conduct a life cycle assessment of global plastic waste trade in 2022 across 18 countries and six plastic waste types, alongside three “nontrade” counterfactual scenarios. By considering the required cycling rate, which balances importers’ costs and recycling revenues, we find that the trade resulted in lower environmental impacts than treating domestically with the average treatment mix. The trade scenario alone reduced climate change impact by 2.85 million tonnes of CO₂ equivalent and mitigated damages to ecosystem quality, human health, and resource availability by 12 species-years, 6200 disability-adjusted life years (DALYs), and 1.4 billion United States dollars (USD in 2013), respectively. These results underscore the significance of recognizing plastic waste trade as a pivotal factor in regulating global secondary plastic production when formulating a global plastics treaty.

The environmental impact of traded plastic waste hinges on how it is treated. Existing studies often use domestic or scenario-based recycling rates for imported plastic waste, which is problematic due to differences in recyclability and the fact that importers pay for it. We estimate the minimum required recycling rate (RRR) needed to break even financially by analysing import prices, recycling costs, and the value of recycled plastics across 22 leading importing countries and four plastic waste types during 2013–2022. Here we show that at least 63% of imported plastic waste must be recycled, surpassing the average domestic recycling rate of 23% by 40 percentage points. This discrepancy suggests that recycled plastics volumes from the global North-to-South trade may be underestimated. The country-specific RRR provided could enhance research and policy efforts to better quantify and mitigate the environmental impact of plastic waste trade.

In terms of mass, construction materials and construction and demolition waste make up the largest part of humankind's material and waste footprints, particularly after an energy transition has largely phased out fossil energy. However, a circular use of building and construction materials is fraught with challenges.

The European Union (EU) has set a 37.5% GHG reduction target in 2030 for the mobility sector, relative to 1990 levels. This requires increasing the share of zero-emission passenger vehicles, mainly in the form of electric vehicles (EVs). This study calculates future GHG emissions related to passenger vehicle manufacturing and use based on stated policy goals of EU Member States for EV promotion. Under these policies, by 2040 the stock of EVs would be about 73 times larger than those of 2020, contributing to a cumulative in-use emission reduction of 2.0 gigatons CO2-eq. Nevertheless, this stated EV adoption will not be sufficiently fast to reach the EU's GHG reduction targets, and some of the GHG environmental burdens may be shifted to the EV battery manufacturing countries. To achieve the 2030 reduction targets, the EU as a whole needs to accelerate the phase-out of internal combustion engine vehicles and transit to e-mobility at the pace of the most ambitious Member States, such that EVs can comprise at least 55% of the EU passenger vehicle fleet in 2030. An accelerated decarbonization of the electricity system will become the most critical prerequisite for minimizing GHG emissions from both EV manufacturing and in-use stages.

Life cycle assessment (LCA) databases and software evolve. We analyzed to which extent software and evolving life cycle inventory databases affect the comparison of technology alternatives, using a comparative LCA on permanent magnets as a case study, with two selected software tools: CMLCA and Brightway LCA. We migrated the system models from the CMLCA to Brightway LCA software and alternated between the ecoinvent database versions 2.2 and 3.1 to 3.6 in the system background. When using ecoinvent v3.6 instead of v2.2, the change of the indicator results ranged from (Formula presented.) to 283%. The evolution of the ecoinvent database impacted the absolute amounts of the characterized results and the relative performance between alternatives. The impact category with the highest variability was ionizing radiation, which even showed a ranking inversion with ecoinvent v3.4. In contrast, the impact of using CMLCA or Brightway was negligible because the same data and modeling assumptions caused percentage differences below 0.4%. During the semi-automated data migration to Brightway, we identified 23 environmental flows in the CMLCA model that were not paired with their corresponding characterization factors in the published study of reference. This error had led to an underestimation of 63% in the photochemical oxidation indicator of one of the alternatives. This underestimation relates to an interoperability issue regarding the nomenclature of environmental flows in software alternatives and is a matter of data implementation rather than an issue intrinsic to the selected software. Finally, we identified improvement opportunities for the transparency and reusability of LCA models. This article met the requirements for a Gold-Gold JIE data openness badge described at http://jie.click/badges.

The construction sector is the biggest driver of resource consumption and waste generation in Europe. The European Union (EU) is making efforts to move from its traditional linear resource and waste management system in the construction sector to a level of high circularity. Based on the theory of circular economy, a new paradigm called waste hierarchy was introduced in the EU Waste Framework Directive. This work uses the framework of the waste hierarchy to analyze the practice of construction and demolition waste (CDW) management in Europe. We explore the evolution of the waste hierarchy in Europe and how it compares with the circular economy. Then, based on the framework, we analyze the performance of CDW management in each EU member state. Innovative treatment methods of CDW, focusing on waste concrete, is investigated. This brings insight into optimizing and upgrading the CDW management in light of advanced technologies and steering the pathway for transitioning the EU towards a circular society.

Offshore wind energy (OWE) is a cornerstone of future clean energy development. Yet, research into global OWE material demand has generally been limited to few materials and/or low technological resolution. In this study, we assess the primary raw material demand and secondary material supply of global OWE. It includes a wide assortment of materials, including bulk materials, rare earth elements, key metals, and other materials for manufacturing offshore wind turbines and foundations. Our OWE development scenarios consider important drivers such as growing wind turbine size, introducing new technologies, moving further to deep waters, and wind turbine lifetime extension. We show that the exploitation of OWE will require large quantities of raw materials from 2020 to 2040: 129–235 million tonnes (Mt) of steel, 8.2–14.6 Mt of iron, 3.8–25.9 Mt of concrete, 0.5–1.0 Mt of copper and 0.3–0.5 Mt of aluminium. Substantial amounts of rare earth elements will be required towards 2040, with up to 16, 13, 31 and 20 fold expansions in the current Neodymium (Nd), Dysprosium (Dy), Praseodymium (Pr) and Terbium (Tb) demand, respectively. Closed-loop recycling of end-of-life wind turbines could supply a maximum 3% and 12% of total material demand for OWE from 2020 to 2030, and 2030 to 2040, respectively. Moreover, a potential lifetime extension of wind turbines from 20 to 25 years would help to reduce material requirements by 7–10%. This study provides a basis for better understanding future OWE material requirements and, therefore, for optimizing future OWE developments in the ongoing energy transition.

The Dutch national climate agreement (‘Klimaatakkoord’), stipulates a 49% decrease in greenhouse gas (GHG) emissions by 2030, relative to the 1990 level. To accommodate this target, the passenger vehicles sector must reduce its GHG emissions by 30% in 2030, which likely will come about by replacing internal combustion engine vehicles with electric vehicles. In this study, a dynamic material flow model combined was applied to investigate the future demand for (and metabolism of) lithium, cobalt, and nickel within various scenarios of Dutch electric vehicle markets stemming from climate policy implementation. Our results show that by 2040 the demand for electric vehicles rapidly grows by an order of magnitude, which expands by two orders of magnitude the annual accumulation of these metals in the Netherlands when compared to the 2019 levels. Lithium and nickel demand will keep increasing through 2040, while the demand trend of cobalt will start to drop after 2030, due to changes in battery technology. Increasing the EV driving range and replacing EV batteries during an EV lifetime will increase the demand for these metals by 10%–19%. Conversely, extending the average battery lifetime to meet the vehicle lifetime could reduce the demand of these metals by 30%. Due to the low open-loop recycling of these metals, policies must seek to minimize their presence in the electric mobility sector, while also stimulating better recycling practices and infrastructure.

Energy efficiency plays an essential role in energy conservation and emissions mitigation efforts in the building sector. This is especially important considering that the global building stock is expected to rapidly expand in the years to come. In this study, a global-scale modeling framework is developed to analyze the evolution of building energy intensity per floor area during 1971–2014, its relationship with economic development, and its future role in energy savings across 21 world regions by 2060. Results show that, for residential buildings, while most high-income and upper-middle-income regions see decreasing energy intensities and strong decoupling from economic development, the potential for further efficiency improvement is limited in the absence of significant socioeconomic and technological shifts. Lower-middle-income regions, often overlooked in analyses, will see large potential future residential energy savings from energy intensity reductions. Harnessing this potential will include, among other policies, stricter building efficiency standards in new construction. For the commercial sector, during 1971–2014, the energy intensity was reduced by 50% in high-income regions but increased by 193% and 44% in upper-middle and lower-middle-income regions, respectively. Given the large energy intensity reduction potential and rapid floor area growth, commercial buildings are increasingly important for energy saving in the future.

Urban mining from construction and demolition waste (CDW) is highly relevant for the circular economy ambitions of the European Union (EU). Given the large volumes involved, end-of-life (EoL) concrete is identified as one of the priority streams for CDW recycling in most EU countries, but it is currently largely downcycled or even landfilled. The European projects C2CA and VEEP have proposed several cost-effective technologies to recover EoL concrete for new concrete manufacturing. To understand the potential effects of large-scale implementation of those recycling technologies on the circular construction, this study deployed static material flow analysis (MFA) for a set of EoL concrete management scenarios in the Netherlands constructed by considering the development factors in two, technological and temporal dimensions. On the technological dimension, three treatment systems for EoL concrete management, namely: business-as-usual treatment, C2CA technological system and VEEP technological system were investigated. On the temporal dimension, 2015 was selected as the reference year, representing the current situation, and 2025 as the future year for the prospective analysis. The results show that the development of cost-effective technologies has the potential to improve the share of recycling (as opposed to downcycling) in the Netherlands from around 5% in 2015 up to 22%–32% in 2025. From the academic aspect, the presented work illustrates how the temporal dimension can be included in the static MFA study to explore the potential effects in the future.