Cleaner Environmental Systems最新文献

Nowadays, coffee is a popular beverage globally and one of the largest traded commodities. Conventional instant coffee production requires energy and water, producing coffee bagasse (biomass) as an agro-industrial residue. This residue, spent coffee grounds (SCGs), in Ecuador is currently disposed of in the municipal landfills, losing the opportunity to recover energy and minerals. This paper studies the life cycle environmental impacts of instant coffee production using data from a coffee plant in Guayaquil, Ecuador. The study analyzes the impact of generating the required electricity by an internal combustion engine powered by fossil fuel, using the Ecuadorian power grid, or using a combined cooling, heat, and power (CCHP) trigeneration system powered by dried SCGs and natural gas. The results indicate that when SCGs is used to power auxiliary processes, the CO₂ emissions greatly decrease, helping to reduce fossil fuel dependence. The study also reveals that scenarios using electricity from the Ecuadorian power grid exhibit lower environmental indicators than those using internal combustion engines. The scenario that includes the CCHP records the lowest indicator in each category, reducing the GWP by 45.2 % compared to the base scenario, pointing out that using energy-efficient technologies lowers the carbon footprint, contributing to decarbonisation simultaneously.

Integrating sustainability into Micro, Small, and Medium-sized Enterprises (MSMEs) poses challenges due to limited resources, low social awareness, and particular cultural factors. Despite this, MSMEs play a crucial role in countries' development since they constitute an essential actor in generating wealth and employment. Therefore, determining tools and methods to support sustainable decision-making and understanding the impacts in MSMEs is a significant challenge. This work describes the application of Social Organizational Life Cycle Assessment (SO-LCA) in three case studies of the Ecuadorian textile MSME sector to analyze their impacts regarding the social dimension. To this end, 121 inventory indicators linked to workers' and consumers' subcategories were applied. Utilizing sunburst charts, social performance is analyzed at subcategory and indicator levels. Company A showed intermediate worker performance with well-managed Occupational Safety and Health (OSH). Company B excelled, particularly in OSH, social benefits, and working hours. Despite its size, Company C had the lowest overall performance but exhibited superior Consumer category performance. This application of SO-LCA in the MSME sector offers insights for systematic evaluation, identifying areas for improvement and commendable practices. The study discusses implementing SO-LCA in small firms, highlighting the need for methodological adjustments to enhance applicability in this sector.

Charcoal plays a relevant role in developing countries, with potential to contribute to the energy needs as a cheaper and carbon-friendly alternative. In Brazil, eucalyptus-charcoal has gained attention as an input for metal-steel industries, mostly supplied by small and medium forest producers. Those commonly use rudimentary charcoal-kilns, characterized by higher greenhouse gas (GHG) emissions, reduced productivity and economically unsustainable impacted by their reduced financial management. In order to fulfill this gap, a simplified financial planning model and an economic analysis of a less polluting charcoal productive system, called kilns-furnace system, were performed, also comparing to traditional charcoal-kilns. A differentiated cost of capital pricing model was also proposed, adjusted to bioenergy projects in emerging markets. Results showed that kilns-furnace system presented the best financial indicators, with greater free cash flow capacity, shorter reimbursement period, reduced charcoal production cost, better return on invested capital and a financial resilience even under pessimistic conditions. With its risk-return ratio verified, kilns-furnace larger insertion may be an attraction for charcoal producers, with probable increased long-term economic sustainability when compared to traditional kilns. The proposed cost of capital pricing model opened a new perspective for its calculation in developing countries, and should be used by producers, companies, and government in investment decision and as a guidance for financing lines.

Wastewater reuse could provide a substantial relief from water scarcity, particularly for agricultural and industrial purposes. To meet future legislation and environmental standards in this regard, organic micropollutants must be efficiently eliminated in the treated effluent. Innovative water treatment technologies can contribute to achieve this goal, but their environmental consequences must be controlled. The objective of this study is to assess the environmental hotspots of an enzyme-based wastewater treatment system for the removal of sulfamethoxazole (SMX) as a model pollutant. For this purpose, the Life Cycle Assessment and Product Environmental Footprint methodologies have been applied to a conceptual process design based on laboratory-scale data. In addition, we addressed the relevant process parameters (i.e., the stability and reuse of the enzyme and the impacts associated with its immobilization), the comparison with consolidated technologies (membrane and ozonation systems) and the geographical situation (such as the electricity mix and the water stress level). The main hotspot of the analyzed treatment process is the production of the unspecific peroxygenase used within the magnetic biocatalyst, contributing more than 36 % to all impact categories considered. Focusing on the magnetic biocatalyst synthesis, the enzyme production phase and the functionalization of the immobilization support are the most problematic (with percentages of up to 75 % in stratospheric ozone depletion and 65 % in terrestrial ecotoxicity, respectively). In relation to resource consumption, water demand has been estimated at 0.02 m³ per cubic meter of treated water, but water deprivation can be much higher depending on the country (∼0.5 m³). Therefore, the use of reclaimed water can offset the indirect effects of its treatment. This study serves as a roadmap for future research to achieve reduced emissions by reduction of energy requirements, the use of renewable energy but also by increasing the enzyme stability. Furthermore, the background environmental impacts of the production of the biocatalyst must be reduced to improve the competitiveness against implemented alternatives based on physical (membranes) and chemical (ozonation) processes.

The environmental sustainability of business activities and operations is an increasingly relevant issue. The Board of Directors, by the means of its monitoring role, affects a firm’s achievement of both economic and non-financial objectives. The nomination committee defines the criteria for the selection of Board members and determines the most suitable profiles of the candidates. This paper studies the effect of the level of independence of the nomination committee on a company’s environmental performance. The study analyzes a sample of European non-financial listed firms for the period 2014–2022. Findings indicate that the level of independence of the nomination committee positively and significantly affects corporate environmental performance and the effect is mediated by the level of independence of the Board of Directors.

Corporate social responsibility (CSR) and its impact on corporate value has been widely debated. Two opposing views have emerged: stakeholder value maximization and shareholder expense. In this study, we explore these perspectives within the realm of mergers and acquisitions (M&A), one of the most important and far-reaching corporate decisions. Specifically, we examine whether the CSR of the acquiring company impacts M&A performance by analyzing a European sample of 1549 M&A deals announced between 2005 and 2019. Our findings indicate that CSR has a negative effect on stock performance around the M&A announcement, which aligns with the shareholder expense view. We argue that in Europe, where corporate social responsibility (CSR) is already elevated as a result of EU policies and regulations, additional CSR investments may not align with the best interests of shareholders. This serves as an illustration of a Too-Much-Of-A-Good-Thing Effect. However, we also see that CSR has no significant effect on operating performance, which may indicate a financial bias of capital market participants or suggests that investors weigh their own cost-benefit considerations when assessing acquirers' CSR performance.

Modern agriculture is linked to desertification, massive biodiversity loss and environmental degradation of the ecosystems. In contrast, crop rotation represents an agronomic approach included in conservation agriculture with important environmental and agronomic benefits, such as N fixation, pest and weed control, improvement of soil characteristics and reduction of crop fertilizer demand. Wheat is a staple food in Morocco, as are legumes, which are present in a wide variety of Moroccan recipes and represent an important source of energy and nutrients. The present study evaluates the environmental performance of incorporating chickpea and lentils in a crop rotation system in Morocco that aims to decrease the environmental footprint of the traditional wheat-based crop. An attributional Life Cycle Assessment was conducted in three cropping systems that are grown in two-year cycles: R1 (chickpea:wheat), R2 (lentil:wheat) and M (wheat:wheat). Emissions were quantified in terms of life-cycle related environmental impacts and compared between cropping systems based on two functional unit (kg of wheat harvested). Rotation systems stand out as the most environmentally friendly, with the most notable reductions in the categories of stratospheric ozone depletion and water scarcity (34 % and 50 %, respectively). The environmental improvement from crop rotations was most significant when considering the calculation basis of hectare cultivated versus kg of wheat, which is due to the estimated yield trade-offs in both approaches. In terms of biodiversity loss, no significant differences were observed between crop rotations and monoculture, as the impact on this indicator is mainly attributed to land conversion pressures. This study provides guidance for better formulating crop rotation strategies in the Mediterranean and similar arid regions. Future research should also assess the effects of agriculture on ecosystem services to provide a more comprehensive analysis to support decision making.

Global agricultural systems are increasingly moving towards organic farming to satisfy consumers’ increased environmental awareness. Yet, shortage of fertilizers and more frequent water stresses are challenging agricultural systems to minimize their environmental impact without compromising productivity and economic sustainability. This study discusses how greenhouse organic tomato production behaves when multiple eco-sustainable solutions are applied. In particular, organic tomato cultivation was supported by a specific biostimulant treatment that included a microbial solution, based on Rhizobium, which was distributed onto faba bean seeds; once a suitable fava bean biomass had been obtained, the plants were chopped and incorporated into the soil in order to release nitrogen. In the trials considered, microbial solutions reduced organic tomato production costs by 5 %. Considering that fertilization accounted for up to 7 % of total production costs, a large-scale preparation of the microbial solution could trigger significant economic savings. The Life-Cycle Assessment shows that organic tomatoes, with a lower yield, have a lower environmental impact than conventional production only for 7 of the 15 evaluated impact categories. Combined agro-technical growing solutions are economically viable in the presence of yields in organic compared to conventional, and their environmental impact is attractive in both scenarios.

Seasonality and within day variation are important characteristics of electricity supply/demand and for emissions from electricity generation. This paper investigates the social costs of using electricity at different times of the day, allowing for seasonal patterns and differences between weekdays and weekends in Sacramento, California in 2013 and 2019. The social costs of electricity use refer to a combination of the emission costs and the electricity price. Using simulations for the social costs of CO₂, results show that the highest costs of using electricity occur at different hours across seasons on weekdays and weekends. As CO₂ price increases, the social costs of electricity use become more volatile, but it becomes more pronounced that the low costs hours shift to daytime hours for most seasons in both years, except summer and spring 2019. This pattern helps evaluate the social impacts of using electricity and providing policy implications for electricity demand changes.

Voluntary carbon offset markets play an important role in climate change mitigation by deploying technologies in order of lowest abatement cost. The objective of this study is to identify the key drivers of changes in the volume of carbon credits issued in voluntary registry offset markets from 2006 to 2020 using a decomposition analysis framework. The results show that the volume of issued carbon credits related to forestry and land use increased from 2006 to 2015 due to priority increases and scale expansions in REDD+ projects. In addition, the reasons for the priority changes in carbon credits issued varied according to the scale of carbon offset programs in each region. The comparison of scale effect and carbon offset program priority is a useful tool for understanding changes in carbon credits issued according to project technology and region. The very rapid increase in forestry carbon credits issued does however pose important policy implications given it has been accompanied by widespread indications of poor governance and questionable outcomes in terms of CO₂ reduction. In light of the IPCC's reliance on carbon credits the need for thoroughgoing policy reform is underlined.