Cleaner Production Letters最新文献

Artisanal and small-scale gold mining is an important livelihood, but also the largest contributor to anthropogenic mercury emissions globally. Two key persistent challenges in reducing mercury use in artisanal and small-scale gold mining communities are effective educational interventions and accessibility to improved technologies. This study evaluates the efficacy of education and equipment distribution interventions to reduce mercury use in artisanal gold mining in Senegalese mining communities. We analyzed the effects of education and retort (mercury-capture devices) distribution through pre- and post-intervention surveys in nine Senegalese mining communities, divided into control, education-only, and education + retort distribution. Educational sessions were conducted in local languages using simple graphics by trusted community members. Retorts were constructed by local metalworkers using locally available materials. The combination of education and retort distribution increased knowledge about the efficacy of retorts and dangers of mercury (94% post-intervention). The combination also increased retort use, from 3% to 64% post-intervention. Retort use in the other two groups also marginally increased. The increased knowledge and retort use observed in control villages suggests a potential social overflow effect of the intervention, extending beyond the locations in which they occurred. Our results indicate that the graphics-based and community-oriented educational approach accompanied by increased access to retorts provides a strong foundation for reducing mercury emissions and exposure to artisanal and small-scale gold mining communities.

Introduction

Decision-makers' perceptions, influenced by institutional and organizational pressures, shape sustainability action. However, the current body of research on the impact of these pressures within the real estate sector, particularly among real estate owner organizations, remains limited.

Research argument

This explorative study fills the research gap by providing empirical findings and theoretical interpretation that explains the influence and outcomes of institutional pressures on decision-making processes.

Methodological approach

Explorative surveys and interviews were conducted with asset managers in Sweden to understand their sustainability perceptions and actions within the real estate sector.

Main findings

The study found a notable shift in sustainability perceptions among asset managers in Sweden, with most recognizing sustainability as critical for commercial real estate, challenging the notion of their passivity and highlighting their proactive engagement. Economic incentives significantly influence sustainability actions, with top priorities being energy efficiency and renewable energy due to their positive business impact. Other sustainability actions are also important but not prioritized to the same extent, revealing specific priorities within real estate owner organizations, an area less explored in prior research.

Conclusion

The article proposes a theoretical framework to guide future research on how institutional and organizational mechanisms shape decision-makers' sustainability perceptions, guiding sustainability action. Understanding these mechanisms is essential for implementing Sustainable Development Goals in practice across industries.

The disruption associated with heat decarbonisation has been identified as a key opportunity for hydrogen technologies in temperate countries and regions where established distribution infrastructure and familiarity with natural gas boilers predominate. A key element of such claims is the empirically untested belief that citizens will prefer to minimise disruption and perceive hydrogen to be less disruptive than the network upgrades and retrofit measures needed to support electric and other low carbon heating technologies. This article reports on exploratory deliberative research with residents of Cardiff, Wales which examined public perceptions of heating disruptions. Our findings suggest that concerns over public responses to disruption may be overstated, particularly as they relate to construction and road excavation for network upgrade. Disruptions arising from permanent changes to building fabric may be more problematic for heat pump retrofit, however these may be greatly overshadowed by anxieties over the cost implications of moving to hydrogen fuel. Furthermore, the biographical patterning of citizen preferences raises significant questions for hydrogen roll-out strategies relying on regionalised network conversion. We conclude by arguing that far from a non-disruptive alternative to electrification, hydrogen risks being seen as posing substantial disruptions to precarious household finances and lifestyles.

In the second half of the 20th century, the behaviour of the world's population has undergone drastic changes: it has grown very rapidly, become longer-lived and moved preferably to urban areas. Migration of populations to cities has a special focus because it not only generates socio-economic development, but also causes different economic, social, and environmental issues. How to assess the sustainable development of cities and identify the most representative aspects of sustainability dimensions has become an essential challenge for effective planning and government policies. However, the selection of indicators has scarcely been addressed when Data Envelopment Analysis (DEA) has been used for sustainability assessment. This paper aims to identify the key indicators to determine the eco-efficient performance towards a sustainable development of a set of cities. For this purpose, the joint use of a variable selection method and a DEA model is proposed and applied to a set of 31 Spanish cities. The results obtained identified five social (population percentage at risk of poverty, number of registered gender violence cases, population density), five economic (average household income, average rental price per m², gross domestic product per capita, public/private vehicle ratio, indebtedness), and three environmental (ozone, NO₂, PM₁₀) indicators for the assessment. Moreover, 14 Spanish cities were considered non-eco-efficient, and targets to achieve eco-efficient levels were proposed. Policy makers could focus primarily on the social and economic aspects of non-eco-efficient cities, paying attention, for example, to the risk of poverty of the population, indebtedness of local governments, average rental price and NO₂ emissions.

Cities concentrate a large amount of people and activities thus being responsible for large amounts of resources being consumed which generate significant impact footprints contributing to climate change both directly and indirectly. In the meantime, circular economy is seen a promising concept to improve resource efficiency. Circular economy strategies are an emerging and important paradigm that can have an important effect in reducing CO₂ emissions.

This study aims at evaluating how circular economy strategies can reduce CO₂ emissions in cities with different contexts to find similarities and differences between them. The studied cities are Beijing, Shanghai, Vienna, and Malmö.

A scenario analysis study is done for two scenarios: 1) Business-As-Usual scenario (BAU) and 2) Circular Economy scenario (CE) from year 2017–2050, using multi-regional input-output (MRIO) analysis. The most CO₂-intensive Exiobase sectors associated with downstream consumption in households and government were identified as CO₂ emission hotspots, and emission reduction targets were identified and applied to these sectors.

The main results from the study show that although Vienna and Malmö have applied sustainability strategies for quite some time, the results do not show that CE strategies work better in the European cities compared with Chinese cities. The results also suggest that the greatest potential and effectiveness in reducing consumption lies in the sectors of energy use and materials consumption for all cities. It can also be seen that CE scenarios have higher potential for CO₂ emissions reduction when compared to the BAU scenarios but the reduction level in Shanghai and Malmö is weaker compared to Vienna and Beijing, which indicates the effectiveness of current CE strategies in reducing Beijing and Vienna's emissions. It also suggests that for Shanghai and Malmö, more ambitious CE strategies should be considered. Finally, comparing the distribution of emissions among the four cities it can be seen that consumption of Beijing, Shanghai and Vienna relies highly on domestic production whilst Malmö is more dependent on international production.

Several countries have revised their targets in recent years to reach net-zero CO₂ emissions across all sectors by 2050, and the transport sector is responsible for a significant share of these emissions. This study compares possible pathways to decarbonise the transport sector including passenger cars, light commercial vehicles and heavy commercial vehicles. To do so, we explore 125 scenarios by varying the share of battery and hydrogen-based fuel cell electric vehicles in each of the three categories above independently. We further model the decarbonisation of the industrial hydrogen demand using electrolysers with hydrogen storage. To explore the potential role of electric and hydrogen transport, as well as their trade-offs, we use GRIMSEL, an open-source sector coupling energy system model of Switzerland which includes the residential, commercial, industrial and transport sectors with four energy carriers, namely electricity, heat, hot water and hydrogen. The total costs are minimised from a social planner perspective. We find that the decarbonisation of the transport sector could lead, on average, to a 12% increase in costs by 2050 and 1.3 MtCO₂/year which represents a 90% CO₂ emissions reduction for the whole sector, compared to fossil-based transport. Second, the transport energy self-sufficiency (i.e. the share of domestic electricity generation in final transport demand) may reach up to 50% for the scenarios with the largest share of battery electric vehicles, mainly due to a smaller energy demand than with hydrogen vehicles. Third, more than three quarters of the industrial hydrogen production is met by local photovoltaic electricity coupled with battery at minimum costs, i.e. green hydrogen. Finally, the use of hydrogen as an energy carrier to store electricity over a long period is not cost-optimal.

Protecting natural forests such as those identified as high conservation value (HCV) areas may facilitate crop production due to the benefit from ecosystem services provided by biodiversity spill-over from adjacent forests. To investigate the effect of protecting contiguous and isolated forests adjacent to oil palm plantations on crop health, we measured the distance between oil palm plots and the continuous forest and forest patch boundaries. We surveyed 715 oil palm sample plots comprising 613 plots in large-scale oil palm plantation and 102 plots in smallholdings that were at least 300 m apart and had a radius of 100 m. Satellite imagery and ancillary spatial data from 2016, 2018, 2019 and 2020 of Negeri Sembilan, Malaysia were used to determine elevation and vegetation indices (VIs). The VIs derived were the Normalized Difference Vegetation Index (NDVI), Enhanced Vegetation Index (EVI), and Normalized Difference Moisture Index (NDMI). Both NDVI and EVI are used to measure the vegetation greenness. The NDMI is used to determine the water content of plants. The VIs are crucial for a variety of applications, including vegetation monitoring, drought research, and agricultural operations. We then used generalized linear models (GLMs) to examine the relationship between VIs and stand-and landscape-level variables. Each VI was used as a response variable, with elevation, distance from continuous forest or forest patches, and oil palm management system (i.e., smallholding and industrial plantation) as explanatory variables. Our results revealed that the chlorophyll sensitive NDVI decreased with increasing distance from continuous forest, but increased away from the forest patches. In contrast, the dense vegetation sensitive EVI increased away from continuous forest, but decreased when distance from forest patches increased. Proximity to continuous forests or forest patches had no effect on the NDMI. All the vegetation indices were lower in smallholdings than industrial plantations. None of the vegetation indices were significantly influenced by elevation. Given that these indices predict palm health and yield, this pattern could result in greater ecosystem services that benefit oil palm growers in oil palm closer to some forest types through the spillover effects of forest biodiversity from continuous forests and forest patches. This study suggests that conservation and industry stakeholders should work together to strengthen the conservation of biodiverse continuous forests and forest patches in HCV standard to develop more-sustainable oil palm agriculture, because of their potential role in supporting ecosystem services.

Hydrogen is an energy carrier with potential applications in decarbonizing difficult-to-electrify energy and industrial systems. The environmental profile of hydrogen varies substantially with its inputs. Water consumption is a particular issue of interest as decisions are made about capital and other investments that will affect the scale and scope of hydrogen use. This study focuses on electrolytic hydrogen due to its path to greenhouse gas neutrality and irreducible water demand (though other pathways might be more water intensive). Specifically, it evaluates life cycle consumptive freshwater intensity of electrolytic hydrogen in the United States at volumes associated with 12 scenarios for a deeply decarbonized 2050 US energy system from two modeling efforts for which both electricity fuel mix and electrolytic hydrogen production were projected (America's Zero Carbon Action Plan and Net Zero America), in addition to volumes for a stylized energy storage project (500 MW hydrogen-fired turbine). Freshwater requirements for hydrogen could be large. Under a central estimate for 2050 US electrolytic hydrogen production, electrolytic freshwater demand for process and feedstock inputs alone (i.e., excluding water for electricity) would be about 7.5% of total 2014 US freshwater consumption for energy (1 billion cubic meters/year, 10⁹ m³/y; [0.2%, 15%] across scenarios, for 2050 electrolytic hydrogen production of [0.3, 18] exajoules, EJ). Including water associated with production of input electricity doubles this central estimate to 15% (2 × 10⁹ m³/y; [1%, 23%] across scenarios). Turbines using electrolytic hydrogen are estimated to be about as freshwater intensive as a coal or nuclear plant, assuming decarbonized, low-water electricity inputs. Although a decarbonized energy system is projected to require less water for resource capture and electricity conversion than the current, fossil-dominated energy system, additional conversion processes supporting decarbonization, like electrolysis, could offset water savings.

In the context of increasing pressure for sustainable production practices, this paper proposes a framework for how production companies could operationalise circular economy principles. The focus is on the production organisation, and how production operations could contribute to strategic circularity change. Prior research has used the Green kaizen methodology to identify environmental aspects and circularity related to the input-output flow of resources at the production shop floor. However, this paper finds that a more comprehensive approach is required, involving all levels of the production organisation. First, the paper defines circular production principles for production operations, showing that these principles vary across different company levels. Operations and shop floor level principles tend to be closer to the production input-output system, whereas factory management level principles are more focused on information sharing and internal and external relations. The circular production principles followed a hierarchical organisational structure with a bottom-up drive, where the allocation of organisational resources increased as the level of the hierarchy increased. The study reveals parallels with Likert's management system, where green kaizen activities are suitable for the shop floor level, but business development requires authority exploitation. Secondly, the paper identifies four circularity impact factors that apply to all company levels. These factors enhance the practical utility and implementation of circularity aspects, making them applicable to all levels of the company. The framework for bottom-up escalation of circular production principles can be used as a roadmap or support for managing a circularity bottom-up transition work. The findings presented in this paper fill a knowledge gap regarding the organisational and managerial work required for circular production. Specifically, this paper addresses challenges related to circular production management, including the gap between strategic targets and operational-driven work. By proposing a comprehensive framework for operationalising circular production principles, this paper offers practical guidance for production companies seeking to transition to circular economy practices.

At a time when the links that bind the oil industry – both corporate and state-owned - to finance and governments seemed inextricable and unquestionable, some major changes have occurred that have prompted major financial players and governments to seek a separation strategy. From the Paris Agreement to the change of administration in the United States, the wind suddenly seems to be blowing in the opposite direction, and many banks change course. The UN-convened Net-Zero Banking Alliance (NZBA) is one prominent example of this new trend. However, banks are only one part of this complex and varied landscape of global finance, which, among institutional investors, includes investment funds, hedge funds, mutual funds, insurance funds, pension plans and ETFs (exchange-traded funds). Despite the promise to divest or reduce investments, global finance still holds profound ties with the fossil fuel sector. The high energy prices due to the war in the Ukraine and concerns over energy security are seemingly strengthening these ties. We provide an insight of the complexity of these interlinkages and explain to what extent the domain of public governance is trying to exert (still insufficient) control over the financial sector under the scope of climate mitigation policies.