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Around 9% of global CO 2 emissions originate from land use changes. Often, these emissions are not appropriately addressed in Life Cycle Assessment. The link between demand for crops in one region and impacts in other regions is referred to here as indirect land use change (iLUC) and includes deforestation, intensification and reduced consumption. Existing models for iLUC tend to ignore intensification and reduced consumption, they most often operate with arbitrary amortisation periods to allocate deforestation emissions over time, and the causal link between land occupation and deforestation is generally weakly established. This paper presents the conceptual framework required for a consistent modelling of iLUC in Life Cycle Assessment. It reports on a novel and biophysical iLUC model, in which amortisation is avoided by using discounted Global Warming Potentials (GWPs). The causal link between demand for land and land use changes is established through markets for land's production capacity. The iLUC model presented is generally applicable to all land use types, crops and regions of the world in typical LCA decision-making contexts focusing on the long-term effects of small-scale changes. The model's strengths and weaknesses are discussed. [ABSTRACT FROM AUTHOR]

Low carbon manufacturing is of growing importance due to the severity of energy shortage and increasing energy costs, as well as a series of environmental problems, i.e., climate change and global warming. This paper investigates the potential of process parameter optimization to minimize carbon emissions during machine processing. A process model of CNC machining is first presented to scope the system boundaries for energy footprint and process efficiency. A multi-objective optimization model is then proposed to explore the impact of cutting speed and feed rate on carbon emissions and processing time. The benefit of the approach is illustrated through a case study of a CNC cylindrical turning process. [ABSTRACT FROM AUTHOR]

The paper analyzes biodiesel chains of rapeseed ( Brassica napus ) and carinata ( Brassica carinata ) cultivated in Central and Southern Italy, assessing the impact on Global Warming Potential by means of the Life Cycle Assessment methodology. The production chains differed in use of the oilcake, as animal feed for rapeseed and as biofumigant for B. carinata . The allocation of emissions across co-products was first calculated on the basis of their energy content according to the criterion proposed by European Commission for biofuel production. The resulting impacts were then compared to those obtained through the substitution approach (system expansion method), which considers emissions that are saved by replacing the equivalent conventional product with co-product bio-based materials i.e. soybean meals, nematicidal fumigants, fertilizers and glycerol. The results showed that this method is sensitive to pointing out the importance of the valorization of co-products to the sustainability of bioenergy supply chain. Among the different options taken into consideration, in the case of the B. carinata biodiesel chain, the substitution of conventional fumigants and fertilizers with biofumigants and amendments is able to determine a global net saving of 134 g CO 2 eq per MJ of biodiesel, reversing the sustainability assessment obtained through the energy allocation method. Overall, the results suggest that, when planning future biorefineries, environmental assessment should take the substitution approach into account in order for valorization of co-products and diversification of processes to be rewarded. [ABSTRACT FROM AUTHOR]

The aim of the paper was to evaluate the environmental burden of the organic waste management systems implemented in Umbria region in Italy, in order to provide useful information for taking strategic decisions aimed at the improvement and optimization. The two most widespread scenarios were analyzed: source-segregated collection followed by organic fertilizer production and not-differentiated collection followed by mechanical and biological treatment and disposal in landfill of the biostabilized material. The environmental performance was assessed through Life Cycle Assessment methodology, assuming one ton of organic waste as functional unit. Most of data for life cycle inventory were provided by actual facilities while background data were obtained from EcoInvent database. The alternative scenarios were compared through the IMPACT 2002+ method and the assessment was carried out on both midpoint and endpoint levels. Results showed that the landfilling of the undifferentiated organic waste has the least impact on the analyzed impact categories, except on the Global Warming, mostly due to the uncollected methane released by the landfill. As regards the aerobic composting of the source-segregated organic fraction, the efforts to reduce the impact should be mainly focused on the reduction of the air emissions (hydrogen sulfide, particulate, ammonia and NMVOC) from the biostabilization process. Furthermore the sensitivity analysis indicated that the increase of the biogas collection efficiency could significantly improve the performance of the not-differentiated collection scenario. [ABSTRACT FROM AUTHOR]

Water contamination by organic compounds is a ubiquitous problem, requiring their removal to meet stringent water quality standards. This paper presents for the first time the life cycle environmental impacts and economic costs of a new water treatment technology for removal of organic compounds known as the ‘Arvia’ process. The impacts and costs are compared with the widely-used granulated activated carbon (GAC) process. Life cycle assessment (LCA) has been used to estimate the environmental impacts and the economic analysis is based on the operating costs. For the GAC system, two scenarios are considered: no regeneration of the spent GAC which is landfilled (GAC-1) and 90% regeneration with 10% of fresh GAC added to replace losses (GAC-2). The LCA results suggest that the Arvia process has lower environmental impacts in comparison to both GAC scenarios for at least seven out of 11 impacts considered. Relative to the GAC-1 scenario, Arvia has 70% lower global warming, acidification, eutrophication, depletion of fossil resources, human, freshwater and marine toxicity. Compared to GAC-2, the reductions in these impacts range between 5% and 50%. However, GAC-2 has lower depletion of elements and ozone layer, photochemical smog and terrestrial toxicity than the Arvia process. The results also show that Arvia has slightly higher operational costs than GAC-2 but significantly lower than GAC-1. [ABSTRACT FROM AUTHOR]

The cement industry sector is one of the largest carbon emitting industrial sectors, and due to the effect of global warming sustainable cement production is increasingly gaining on importance. Controlling the combustion of coal and the thermal degradation of limestone, the two main thermo-chemical processes that occur inside a cement calciner, is of significant importance, since these processes have a direct influence on the cement quality, pollutant formation and overall energy efficiency of the cement manufacturing process. One of the possibilities for the improvement and control of these thermo-chemical processes are Computational Fluid Dynamics – CFD simulations. The results gained from these simulations are being increasingly used to enhance the efficiency of cement production, since they improve the understanding of the flow characteristics and transport phenomena taking place inside the cement calciner. The purpose of this paper is to present that a more energy efficient and sustainable cement production can be achieved by deploying CFD simulations in the process of cement production. The numerical models of limestone thermal degradation, also known as the calcination process, and pulverized coal combustion were developed and implemented within the commercial computational fluid dynamics code FIRE, which was then used for the analysis. The developed models are based on the solution of Navier–Stokes equations for the gas phase, and on the Lagrangian dynamics for the discrete particles. A three dimensional complex geometry of a real industrial cement calciner was used for the CFD simulation. The information obtained from this numerical simulation, such as the distribution of particles, distribution of temperatures and the concentrations can be used for better understanding of particle kinetics and pollutant emissions from the given cement calciner and also for its further investigation and optimization. [ABSTRACT FROM AUTHOR]

Various environmental regulations put ever stringent requirements on the automotive industry as a part of solution to the problem of global warming and climate change. In Europe, the upcoming Euro 6 standard that will come into force on September 1, 2014 demands reduction in NO x emissions from cars and vehicles intended for transport by more than 50% compared to the current standard. The urea-water-solution (UWS) based selective catalytic reduction (SCR) is currently the most promising method for fulfilling these requirements. In principle, the UWS spray is injected into a hot exhaust gas stream preceding the SCR catalyst and ammonia is generated through series of chemical reactions. Then, the generated ammonia acts in various deNO x reactions as a reductant. This paper investigates application of numerical modeling in the area of environmentally friendly technology of mobile SCR as a green engineering measure to reduce pollution in the road transport sector. Within this work the mathematical model of surface tension has been developed and compared to analytical expression for isothermal droplet spreading. Furthermore, this model was incorporated into the wall film module of the commercial computational fluid dynamics code FIRE for description of urea-water-solution injection into hot exhaust gases of diesel engine and compared to experimental data. Results of the conducted numerical study support the feasibility of commercial application of the presented model. [ABSTRACT FROM AUTHOR]

The purpose of this study is to assess whether for dry biodegradable packaging without food contamination, a detailed life cycle assessment supports the priorities suggested by the five-level hierarchy, as described by the European Waste Directive 2006/12/EC. Environmental impacts and water withdrawal were assessed using an extended version of IMPACT 2002+, accounting for the dynamic pattern of greenhouse gas releases for each scenario when determining Global Warming Potentials for a time horizon of 100 years (in this paper defined as dynamic assessment). The present assessment shows that, for most impact categories, mechanical recycling is the most interesting option, followed by direct fuel substitution. Intermediate performances are obtained by anaerobic digestion and municipal incineration. Landfill and industrial composting of dry packaging generate the highest environmental impacts of the studied end-of-life options. Indeed, the composting of the studied materials does not substantially improve compost quality and does not enable energy recovery. The hypothesis that composting is by default environmentally preferable over energy recovery because it is a form of recycling is not confirmed by the present study, thus underlining the importance of a sound and case-specific application of the EU waste hierarchy and the need to complete the hierarchy by product specific studies. Though of limited effect on the present study, the dynamic assessment of greenhouse gas may moderately decrease the impacts effectively taking place over the 100-year horizon. More important is to consider the degradation patterns of biodegradable materials and present to the decision makers both the 100-year and the long term impacts of the end-of-life options. [ABSTRACT FROM AUTHOR]

The simplification of life cycle inventories (LCIs) by reducing the number of elementary flows is a major issue regarding their use in sector-specific applications. It can ease the understanding of complete LCIs and focus on the most relevant elementary flows. Current LCIs that have been created for Environmental Product Declarations (EPDs) differ from databases provided by academics, in which more than a thousand flows are considered, as they contain a reduced list of substances. In this paper, we examine the consequences of these simplified LCIs on the accuracy of the life cycle impact assessment (LCIA) step. We consider the specific case of an LCI database for building products that was developed in France. Three environmental midpoint and endpoint indicators are analysed: the global warming potential (GWP), the photochemical ozone formation potential (POCP), and the disability-adjusted life years (DALY). The results for 110 building materials indicate that a simplification is not always relevant, as large uncertainties were detected in the final results, especially for the environmental indicators describing the photochemical ozone creation and the damage to human health that require a larger number of LCI flows. In the case of the GWP indicator, the simplification is relevant for approximately 95% of the building materials. The analysis of the key elementary flows for each indicator enables the identification of missing elementary flows in the simplified LCI. Perspectives and recommendations are provided to improve the level of details of simplified LCIs according to the impact assessment methods. [ABSTRACT FROM AUTHOR]

Global-level warming largely influences drought dynamics. Therefore, a robust drought projection is critical to support sustainable development under a future warming climate, especially at the regional level (i.e., South Asia). Encouraged by the Paris Agreement, this study investigates the changes in the intensity, area, and duration of future droughts under 1.5 °C, 2.0 °C, 3.0 °C, and 4.0 °C global warming levels over South Asia. In this regard, seven global climate model outputs under seven newly designed climate change scenarios (SSP1-1.9, SSP1-2.6, SSP2-4.5, SSP3-7.0, SSP4-3.4, SSP4-6.0, and SSP5-8.5) from the sixth phase of the Coupled Model Intercomparison Project (CMIP6) are used. The standardized precipitation evapotranspiration index (SPEI), self-calibrating Palmer drought severity index (scPDSI), and intensity-area-duration (IAD) method are adopted to characterize drought. Drought events are identified considering an area coverage greater than 50,000 km2 for predefined drought durations of 3- (short-term), 6- (medium-term), and 12-month (long-term). A significant drying trend is seen and tested against the two-sample t -test. Notably, to represent the more concrete picture of changes in drought characteristics, the results based on two indices (SPEI and scPDSI) are combined (average) in this paper. The results reveal that droughts with higher-intensity, and long-term duration will increase with continued warming. As drought features, the number of long-term droughts will increase by 21.5% (highest), and the leading area coverage is also estimated (>7%) for long-term drought at higher warming (i.e.4.0 °C) than the reference period (1995–2014). Furthermore, drought events with large-area (>3 × 105 km2) coverage are projected to become more frequent. For drought severity, extreme drought events and associated area coverage are more likely to unfold over the region. However, overall drought conditions are inclined to worsen under higher warming, especially 4.0 °C warming. Importantly, for global warming targets set by the Paris Agreement (1.5 °C and 2.0 °C), drought conditions will be more acute at 2.0 °C than at 1.5 °C. Spatially, a significant drying trend is mainly observed in the western part of South Asia (Southwest-Northwest) according to both drought metrics (SPEI and scPDSI). Notably, NW will experience acute droughts under all warming levels. Droughts in this region will be mainly influenced by the combined effect of decreasing precipitation and escalated evapotranspiration. As global warming increases, a significant increase in PET and temperature is found over South Asia. In addition, the model evaluation shows that the CMIP6-Global climate models (GCMs) are capable of satisfactorily reproducing climate variables and drought events in South Asia. However, our study's findings strongly support the execution of the Paris Agreement target and provide a scientific basis for articulating drought adaptation measures at the regional scale, especially in South Asia. • Intensity-Area-Duration approach is used to analyze future drought over South Asia for 1.5oC - 4.0oC warming. • The modified Penman-Monteith method (considering CO 2) are adopted to estimate PET. • Overall drought conditions will worsen under 4.0oC warming. • The Northwest of South Asia is inclined to be affected by intense drought in the future. [ABSTRACT FROM AUTHOR]

Given the severe global warming situation, it is very important to explore the factors influencing carbon emission intensity and accurately analyze the trends in the development of carbon emission intensity to achieve the goal of reducing carbon emissions. In contrast with the existing research, this paper starts from the perspective of carbon emission efficiency, applies stochastic frontier analysis to screen the factors influencing carbon intensity, and constructs a model for predicting carbon emission intensity based on factor analysis and an extreme learning machine. The results suggest that, first, there is a high correlation between carbon emission efficiency and carbon emission intensity. Second, the level of economic development, industrial structure, urbanization level, and government intervention all promote a reduction in carbon emission intensity. The structure of energy consumption and dependence on foreign trade restrain reductions in carbon emission intensity. Finally, the proposed model accurately predicts carbon emission intensity. The research results provide theoretical support for the development of technologies to reduce carbon emissions. This idea can be applied to predict carbon emission intensity in different regions and has practical significance. [Display omitted] • Carbon efficiency is related to carbon intensity. • Indicators of carbon efficiency work in reverse on carbon intensity. • Energy consumption and foreign trade restrain the reduction of carbon intensity. • Economic, industrial, urbanization and government promote the reduction. [ABSTRACT FROM AUTHOR]

This paper estimated the environmental performance and primary energy consumption of a newly installed large-scale solar photovoltaic system of 37.57 MW dc in Bidor, Malaysia using the process-based life-cycle assessment approach. The mid-point and end-point impact categories were evaluated, and seven relevant indicators related to energy and global warming were determined. The global warming impact and energy payback time obtained were 30.95 g CO 2 -eq/kWh and 3.43 years, respectively. Furthermore, the global warming impact mitigation potential attained was 811 kilo metric tonne (ktonne) CO 2 -eq throughout the system lifetime. Analyses of contribution, sensitivity and uncertainty were performed to i) identify photovoltaic system components that substantially consumed primary energy and impacted the environment, ii) evaluate the effect of four key parameters, namely irradiation, performance ratio, system lifetime and electricity mix on the energy and global warming-related indicators, and iii) estimate the uncertainty range of the evaluated indicators. The results highlighted that the main contributor to the indicators is the photovoltaic module. Other significant contributors are the civil work and operational and maintenance but the contribution from these components is much lower than the photovoltaic module. Besides that, the cumulative energy demand, energy return on investment, global warming impact and global warming impact mitigation potential showed an improvement when extending system lifetime from 15 to 40 years, i.e. from 0.8136 to 0.3677 MJ, 4.61 to 11.25, 55.37 to 24.99 g CO 2 -eq/kWh and 407.36 to 1055.78 g CO 2 -eq respectively, except for energy payback time and global warming payback time, i.e. from 3.26 to 3.55 years and 1.42 to 1.71 years respectively. • A life-cycle assessment of a real large-scale solar photovoltaic system is performed. • Extending lifetime of the system marginally increases the energy payback time. • The GW impact is about 19 times smaller than the Malaysian grid emission factor. • PV module is the major contributor to total primary energy consumption and GW impact. • BOS and O&M have a moderate share for primary energy consumption and GW impact. [ABSTRACT FROM AUTHOR]

Wood pallets play a critical role in the movement and storage of goods worldwide. They are an important component in the complex global supply chain and used by almost every industry. It is therefore important to assess the environmental implications of the wood pallet supply chain and identify optimization strategies that can be implemented. In this paper, primary 2018 annual production data collected from U.S. pallet manufacturers were used to develop the first industry-average life-cycle inventory (LCI). A new functional unit was proposed to perform a more refined and accurate environmental life-cycle assessment of the wood pallet supply chain. Using the LCI data developed, a cradle-to-grave industry-average life-cycle impact assessment was performed. This novel approach quantifies environmental impacts of a generic multi-use pallet, including repair and remanufacturing. The total global warming impact was 10.4 kg CO 2 e per 45.4 t of pallet loads of product delivered using wood pallets. The manufacturing stage contributed the most, about 35%, followed by the raw material supply stage. About 41% of total primary energy consumption was from renewable sources, with most sourced from biomass. Fossil fuels comprised about 52% of the total (225 MJ per functional unit) primary energy consumption. Total environmental impact was significantly affected by two main parameters: reference service life and load-bearing capacity. Pallet repair was also found to be an important component of the wood pallet supply chain, which has a low environmental footprint compared with the overall impact of a pallet and enables mitigation of overall impact by extending the reference service life. At end-of-life, common industry practices demonstrated substantial potential environmental benefits that can minimize overall environmental impact. The first industry-average wooden pallet life-cycle assessment based on a novel primary dataset. A unique functional unit developed based on pallet characteristics and load-carrying capacity. Global warming impact was 10.4 kg CO 2 e per functional unit. Raw material supply and manufacturing stages dominated the environmental impacts. Scenarios analyses showed the importance of repair and end-of-life pathways. [ABSTRACT FROM AUTHOR]

Concrete is responsible for a significant share of global GHG emissions, which can be mainly ascribed to the production of clinker. Alkali-activated concretes have been investigated in literature as a possible alternative, but the sustainability still appears reduced by the high embodied energy of chemicals typically used for the activation step. This paper investigates concrete belonging to strength classes 35, 50 and 70 MPa and produced with a silicate activator derived from waste glass (AABR). Through a Life Cycle Assessment (LCA), the investigation aims to compare the AABR to Ordinary Portland Cement (OPC) concrete and alkali-activated concrete produced with commercially available chemicals (AABC). The effects produced by the variations of some key parameters (impact allocation of precursors, energy mix, amount of activator in the concrete, distance of procurement of raw materials) over the total impact of the AABR are also investigated. Results show that the adoption of alkali-activated concretes instead of OPC concrete allows a significant reduction in environmental categories of global warming (averagely 64% reduction for AABC and 70% for AABR), acidification potential (averagely 23% for AABC and 35% for AABR), and terrestrial eutrophication (averagely 53% for AABC and 60% for AABR). In addition, the study evidenced that the use of waste glass-based activator allows a significant reduction in every environmental category when compared to the use of commercially available chemicals. • LCA was carried out on alkali activated concrete with waste-derived activator. • Comparisons to OPC and AAC with commercial activators were performed. • AAC with waste activator allows 70% reduction of global warming. • Waste derived activator has lower impacts than commercially available chemicals. • Impacts of key parameters from the use of waste-derived activator were assessed. [ABSTRACT FROM AUTHOR]

Cyanobacterial blooms under global warming are increasing worldwide, producing emerging contaminants, which threaten the health of human beings and aquatic ecosystems. The health burdens warrant the development of a useful risk-assessment tool and a holistic preventive-control scheme to prevent cyanobacterial blooms. This paper aims to integrate cyanobacterial risk assessment and risk preventive control by investigating the relationships amongst cyanobacterial blooms and multi-dimensional influencing variables. Two challenges hinder such a task. First, the time-series variations in cyanobacteria and influencing variables are uncertain and nonlinear. Second, there rarely exists an explicit modelling framework for integrating cyanobacterial risk assessment and risk preventive control. This study builds an extended Bayesian network model and proposes an integrated framework with functions of assessment, inference, preventive control, and visualisation of the risk of cyanobacterial blooms. Field data from a tropical lake are used to evaluate the model and framework. The proposed model achieves better performance than the seven models in comparison. The cyanobacterial risk is anticipated to increase by 38.5% under global warming. On the contrary, guided by the model and framework, the risk could be reduced by about 60% by taking the identified risk preventive control scheme. The cyanobacterial risk prevention would reduce aquatic emerging contaminants in drinking and recreational water sources. [Display omitted] • The cyanobacterial multivariate system was modelled by an extended Bayesian network. • The risk assessment and preventive control of cyanobacterial blooms were integrated. • The proposed model achieved better performance than the seven models in comparison. • The cyanobacterial risk was anticipated to increase by 38.5% under global warming. • The risk was reduced by about 60% if taking the proposed preventive-control scheme. [ABSTRACT FROM AUTHOR]

Tourism, and thereby hotels, play a crucial role in the European economy. The hotel sector features high energy consumption, which greatly contributes to the global warming effect. Thus, there is a need to investigate environmentally friendly technologies that have the potential to reduce energy usage within this sector. Information regarding the current status of the energy consumption in hotels is essential. Therefore, a study of 140 hotels in Norway and Sweden is presented in this paper to identify successful and sustainable measures to reduce energy consumption and related emissions. The energy use, available energy sources and thermal systems in the hotels are studied over a five-year period to identify consumption trends. The results reveal that 70% of the hotels have a mean annual energy consumption between 150 and 250 kWh/m2. A shift towards sustainable energy sources is observed in the hotels from 2015 to 2019, where application and overall consumption of district heating and cooling have increased, while electrical energy consumption has been reduced. District heating is the most prominent source of heating and is applied as the primary heat source in 70% of the hotels. The specific energy consumption for the group hotels that apply district heating is 218.9 kWh/m2/year, which is nearly 25% higher than the specific energy consumption of the 9% of hotels that apply heat pump solutions as a primary heat source. Thus, there is a potential to reduce the specific energy consumption in hotels. Two integrated transcritical carbon dioxide (CO 2) heat pumps were investigated as a sustainable measure to reduce energy consumption. The results reveal that a reduction of thermal energy consumption of approximately 60% can be achieved. • Energy analysis of 140 hotels in Norway and Sweden. • District heating and cooling in hotels increased by 18.0 and 10.9% from 2015 to 2019. • Hotels with heat pumps use 19.9% less kWh/m2 than hotels with district heating. • CO 2 heat pumps in hotels can reduce thermal energy consumption by about 60%. [ABSTRACT FROM AUTHOR]

Recent reports by the Intergovernmental Panel on Climate Change (2018 and 2019) have revealed that world's human activities have contributed to around 1 °C of global warming above the pre-industrial levels (expected to reach 1.5 °C between 2030 and 2052) with the burning of fossil fuel contributing to over three-quarters of world's emissions. Rising demand for energy is expected to add another 39 billion tonnes of carbon-dioxide, threatening the climate action plan of achieving net-zero by 2050. Given the expected worsening of emissions from fossil fuels' burning, this paper's main objective is to empirically examine the supply-side effect of energy generation from fossil fuels (coal, natural gas and oil) on environmental quality. In doing so, an extended Stochastic Impacts by Regression on Population Affluence and Technology (STIRPAT) model is adopted that controls for a range of economic, social and institutional factors. The panel data estimation technique is applied to the model that includes a balanced panel of 59 countries using coal, 77 countries using gas and 96 countries using oil for 2002 to 2016. The results revealed coefficient coal is negative and statistically significant at the 1 per cent level (α = −0.052 with ρ = 0.01) and oil is negative and statistically significant at 5 per cent level (α = −0.020 with ρ = 0.05). These results support supply-side energy generation through the burning of coal and oil as vital contributors to environmental quality degradation. Other than confirming the Environmental Kuznets Curve (EKC) effect, forest cover, schooling, the rule of law and nations commitments to international environmental treaties are other strong correlates of environmental performance. The findings also revealed strong adverse effects of agriculture and industrial intensification on environmental quality. The main conclusion is the urgency for the worlds fossil fuel energy-dependent countries to transit from fossil fuel energy to the production of frontier renewable (cleaner forms) sources of energy to minimise degradation of the environment. Other than exploring supply-side carbon mitigation policies, there is a need for active co-operation of all countries of the world in the enforcement of international treaties to minimise further environmental damage. • The effect of fossil fuel energy production on environmental quality is studied. • The sustainable energy and environmental outcomes framework is adopted. • The analysis uses the STIRPAT model for the period 2002 to 2010. • Coal and oil led energy production are associated with environmental degradation. • The adoption of sustainable energy production policies is essential. [ABSTRACT FROM AUTHOR]

As an emerging carbon offset mechanism, the Chinese Certified Emission Reduction (CCER) scheme can theoretically supplement the emissions trading scheme (ETS) to alleviate global warming. However, due to poor data availability and short implementation time, little effort has been made to understand the mechanism and driving factors of the CCER scheme. To fill these gaps, this paper establishes a system dynamics model with feedbacks to analyze the coupling effects of the ETS and the CCER scheme. Three scenarios, including a baseline scenario (BAU scenario), a single trading market scenario (i.e., ETS market only), and a double trading market scenario (i.e., both the ETS market and the CCER market), are considered. The simulation results reveal that compared with the BAU scenario, both the single trading market scenario and the double trading market scenario can accelerate the mitigation of CO 2 emissions, reduce abatement costs, and transform the energy structure. Interestingly, in the double trading market scenario, although CO 2 emissions are slightly higher and the renewable energy proportion is slightly lower than that in the single trading market scenario, the additional cost-saving effect of the double trading market scenario over time increases significantly. Besides, to fulfill the Intended National Determined Contributions (INDCs) as closely as possible, governments need to set a rational offset rate of CCER quotas and to stabilize the carbon quota trading price. These findings enrich the relevant knowledge in the field of climate change by providing implications for the design of novel carbon offset instruments. [ABSTRACT FROM AUTHOR]

The abatement of carbon emissions is an important way to alleviate global warming. It is therefore crucial to explore the factors behind the corporate proactivity of carbon emissions abatement (CPCEA). However, existing research mainly focused on the factors that promote national, provincial, city-level, and industrial carbon emissions reduction, without looking at the micro-company level. In response to the research gap, this study therefore explored the drivers of CPCEA using panel data from 736 listed companies in China. This study used the logit regression to examine the effects of pre-identified factors on the CPCEA. The results indicated that political ties, corporate scale, industry category, and regional disparity have significant impacts on the CPCEA. Contrary to expectations, environmental regulation was not found to affect CPCEA. Based on the findings of this study, five policy implications to improve CPCEA in China were proposed. This paper presented empirical evidence to promote CPCEA. Additionally, the results have important practical implications and priority guide for carbon emissions reduction in China and around the world. Image 1 F09F • Political ties are negatively related to the corporate proactivity of carbon emissions abatement (CPCEA). F09F • Corporate scale is positively related to the CPCEA. F09F • Companies in the higher carbon industries and companies in the more developed region have stronger CPCEA. F09F • Environmental regulation has no significant impact on promoting CPCEA. [ABSTRACT FROM AUTHOR]

The implementation of renewable energy brings numerous advantages including reduction of power transmission cost and minimization of the global warming problems. The investigation of the influencing operational parameters as well as optimization of the solar energy system is the key factors to enhance the power conversion efficiency. The different optimization methods in solar energy applications have been utilized to improve performance efficiency. However, the development of optimal methods under the intermittent nature of solar energy resources remains key issues to be explored. Therefore, this paper presents a comprehensive review of the main generic objectives of optimization in renewable energy systems, such as solar energy systems. Moreover, this study introduces the most recent intelligent optimization methods used in solar energy systems with regard to its functions, constraints, research gaps and contributions. From this review, it can be concluded that the main objectives of optimizations methods are to reduce minimize investment, operation and maintenance costs and emissions to enhance the system reliability. This review also outlines a brief discussion of various challenges and issues of solar energy optimization. Finally, the review delivers some effective future directions toward the development of an efficient and stable solar PV system. • A comprehensive review on the optimization objectives in solar energy systems are explained. • Intelligent control strategies and optimization methods are utilized in solar energy systems. • Optimizations strategies reduce emissions and costs of system into maximizing reliability. • Solar energy systems enhance the output power and minimize the interruptions in the connected load. • This review highlights the challenges on optimization to increase efficient and stable PV system. [ABSTRACT FROM AUTHOR]

Global warming is one of the biggest challenges that we are facing today. Construction industry is also contributing to the problem by emitting greenhouse gases. In order to deal with this issue sustainable products are being adopted by all the industries. Similarly, highway industry is also adopting several measures to reduce its carbon footprint. One of such measures is cold mix asphalt technology (CMA). CMA does not require any heating of material. This is achieved by using asphalt emulsion and cutback as binding material. Since these materials are liquid at room temperature, they do not require any heating for mixing and compaction. This gives many environmental and economic benefits to CMA over hot mix asphalt (HMA). Despite having these advantages, inferior performance makes CMA undesirable to be used in the construction of roads having high density traffic. Although some studies have been taken to improve the performance of CMA but those are limited in their scope. Present paper gives an overview of the different aspects of CMA technology. It discusses materials, design procedure, field utilisation, performance, effect of different performance enhancing measures of CMA. In the end benefits, drawbacks and future scope of CMA are also presented. [ABSTRACT FROM AUTHOR]

Due to the significant effects of CO 2 emissions on climate change and global warming, as well as its serious hazards to human health, the prediction of CO 2 emission is a vital issue. The main aim of this paper is to evaluate the power of the Inclusive Multiple Model (IMM) as a novel approach to predict CO 2 emission in the agriculture sector of Iran. For the same, we implemented the environmental Kuznets curve (EKC) specification and data from 2003 to 2017 for 28 provinces of Iran. In the first level, various specifications were implemented for each of the Multiple Regression (MLR), Gaussian Process Regression (GPR), and Artificial Neural Network (ANN) models. In the second level, an IMM model was implemented for treating the outputs of the best specification out of the MLR, GPR, and ANN models as inputs to an ANN model. The performance of the models was compared with the Taylor diagram and innovation and unique graphs. Findings indicated that the IMM model with C C = 0.81 , RMSE = 0.69, the highest residuals between −5 and 5 (37.84%), and the lowest distance from observation points (1.857) estimated CO 2 emission values more precisely. These improvements indicate that there are possible directions for future research activities. Due to the most accuracy of the IMM, it is recommended to use this method to predict CO 2 emission to adopt appropriate policies for reducing air pollution. Image 1 • We developed Inclusive Multiple Model (IMM) as a novel approach to predict CO 2 emission in the agriculture sector of Iran. • We utilized Environmental Kuznets Curve (EKC) hypothesis literature to predict CO 2 emission. • We used the Taylor diagram with distance and new graphs to determine the most accurate model. • A measure of income inequality could improve results in investigating EKC. • The IMM was the most accurate model according to all of performance metrics and diagnostic graphs. [ABSTRACT FROM AUTHOR]

Litter decomposition is a vital component of carbon and nutrients cycling and energy flow within terrestrial ecosystems. Understanding the litter decomposition rate with a temperature change of 1 °C (k DD , degree days−1) is critical for quantifying the climate-carbon, nutrients, and energy cycle feedback and predicting the response of ecosystems to climate change. However, the spatial pattern of k DD is uncertain, given differences in litter quality and soil property responses to temperature. Therefore, our goal was to explore the spatial patterns and driving factors of the k DD with a synthesized dataset, which included 1370 individual studies from 253 publications and accumulated daily temperature of each site from 389 meteorological stations. The dataset covered forest, grassland, and cropland ecosystems. The k DD significantly decreased with increasing latitude and varied with climate variables, litter quality, soil properties, and experimental duration under different ecosystems. The averaged k DD in the forest, grassland, and cropland ecosystems were 1.30, 2.23, and 3.35 × 10−4 degree days−1, respectively. The k DD markedly decreased with the increase of experimental years. Climate variables [mean annual temperature (MAT) and precipitation (MAP)] accounted for 36.8% of the total variance in the k DD , followed by soil properties (e.g., soil sand content and pH; 28.1%); experimental duration (23.0%); and litter properties (e.g., nitrogen and lignin; 12.1%). MAT and MAP had substantially indirect effects on k DD via regulating soil and litter properties. Lignin directly and negatively affected k DD. Higher correlations between k DD and litter properties were maintained if the effects of climate, soil properties, and experimental duration were removed. Overall, our findings highlight that intrinsic (litter properties) and extrinsic (climatic and soil properties) variables directly and indirectly regulated the k DD at a regional scale, respectively, providing a framework for optimizing the ecosystem process model to global warming scenarios. Meantime, these results clarify the crucial role of environmental variables in regulating the k DD , potentially affecting the terrestrial carbon, nutrients, and energy-climate feedback. Image 1 • The highlights of the paper are as follows: • Litter decomposition rate significantly decreased with increasing latitude and experimental time. • A network of climate, soil properties, and litter properties determined litter decomposition rate. • Intrinsic and extrinsic variables directly and indirectly regulated litter decomposition rate. [ABSTRACT FROM AUTHOR]

To mitigate global warming, CO 2 emission reduction has become an urgent issue in the energy sector. In China, coal-to-gas, carbon capture and renewable energy utilization are important measures available among various low-carbon plans. However, inadequate gas supply, unclear utilization methods of captured CO 2 , and curtailment of excessive wind and solar power have hampered the effective implementation of the above measures. To solve this issue, this paper presents a coupling model considering power to gas (P2G) technology and carbon capture power plants (CCPP), and extends it into an integrated energy system (IES) including electricity, thermal and gas, then proposes an economic and environment-friendly scheduling model at a high wind power penetration level. Through the coupling of CCPP and P2G in IES, most of CO 2 emitted by the system can be captured and sent to the P2G facility to produce synthesized gas, which provides a new idea of utilizing CO 2 rather than storage. The synthetic gas can be provided to the system to reduce the external gas dependency. In addition, the simulation results also show that the ability of the system to absorb renewable energy is significantly enhanced with the presence of CCPP and P2G. [ABSTRACT FROM AUTHOR]

Global warming caused by greenhouse gases (GHG) emissions has become a paramount problem for all countries to solve. The construction industry emits 36 percent of the GHG in all sectors globally. China is the largest carbon emitter in the world, and Jiangsu province has been used as a test bed for reforming and developing modern construction industry in China. The aim of the study is to explore the driving factors of the total carbon emissions from the construction industry (CECI) in the provincial region using a hybrid Logarithmic Mean Divisia Index (LMDI) model. The findings of the study indicate that: 1) Indirect and operational CECI account for the largest proportion (52.22% and 46.02% in 2016 respectively); 2) The driving factors of CECI in Jiangsu province are the area factor (contribution from 2005 to 2016 is 100.22%) and the output value intensity factor (86.56%) while the restraining factor is the carbon emission intensity (−80.35%). Discussion and implicated policies, such as improving the energy efficiency of related industries and using green building materials have been elaborated at the end of the study. The decomposition and calculation method presented in this paper provides a useful tool for policymakers to evaluate CECI of a province or state and formulate appropriate carbon policies to reduce emissions and promote low-carbon development in a region. [ABSTRACT FROM AUTHOR]

One important opportunity to reduce energy waste and global warming is renovation, retrofit, and refurbishment of existing buildings. Adding a multi-layer internal insulation is an efficient way to upgrade an existing housing into a nearly zero-energy buildings, NZEB. There is a vast variety of products and solutions for the building envelope with different environmental impacts. In this paper a methodology is presented to establish a two-criteria framework to rank thermal insulation materials to be used in the envelope. The objective was to design an optimal insulation system based on a multi-objective approach to maximize the energy saving and minimize the environmental impact. Using twelve typical insulation materials with different thicknesses, a four-layer insulation system was developed and applied to a Case study, a typical multi-story apartment building located in a hot summer and cold winter zone. Results revealed there are several optimum solutions to significantly reduce the building energy consumption, with important differences in their environmental impacts. For the case study, eight Pareto-optimal solutions were derived using the two-objective optimization offering more than 70% reduction in the energy demand, and a global warming potential range of 192–1500 kgCo2 eq. [ABSTRACT FROM AUTHOR]

Fly ash is increasingly used for producing sustainable concrete. This paper outlines a procedure for the optimal mixture design of air-entrained fly ash-blended concrete considering carbonation and frost durability. First, the aim function of the optimization is set as the total cost, which equals the material cost plus the CO 2 emission cost. Constraints such as mechanical, workability, carbonation, and frost durability properties are considered during the optimization design procedure. The carbonation model considers the effect of global warming, including increasing CO 2 concentration and environmental temperature. Second, a genetic algorithm is used for determining the optimal concrete mixtures. A total of 12 design examples are prepared for various frost exposure conditions (including mild, moderate, and severe exposure), and the effects of the carbonation durability and climate change on the mixture design are highlighted. According to the results, 1) for ordinary-strength concrete (design strength of 30 MPa), the carbonation durability is the decisive factor in the mixture design, and the actual strength should be greater than the design strength; 2) for high-strength concrete (design strength of 45 MPa), strength is the decisive factor in the mixture design, and the actual strength can equal the design strength; 3) for a particular entrained air content, the total cost of concrete increases with increasing concrete strength. In summary, the proposed method is a general and useful approach for designing air-entrained fly ash-blended concrete considering sustainability and durability. Image 1 • Propose optimal mixture design method of low cost and low CO 2 blended concrete. • Clarify the effects of carbonation durability and climate change on the optimal mix. • Sustainability, durability, and profit are considered in an integrated manner. • Clarify the control factor for the mixture design of various strengths concrete. • The proposed design method is flexible to fit various design codes. [ABSTRACT FROM AUTHOR]

While strong focus has been recently given to the environmental burdens of diets, more research is needed at the daily eating patterns, specifically, at the meal level. In this regard, this study attempts to enlarge this knowledge by evaluating the environmental performance of meals eaten away from home. In particular, this paper focuses on the case of shared dishes, known as tapas, eaten in a Spanish restaurant. To do so, the life cycle assessments (LCA) of 15 tapas meals are performed, and a functional unit based on the caloric energy intake and the nutritional quality of the meals is applied. This novelty, at the meal level, allows the integration of both environmental and the nutritional aspects, and, therefore, the comparison between meals differing in energy and nutrient content. Additionally, to better assess and compare the performance of the meals, this study estimates the benchmarks for the three evaluated environmental impacts - Global Warming Potential (GWP), Blue Water Footprint (BWF) and Land Use (LU) – based on the Planetary Health Diet. The results suggest that shifting towards a planetary health tapas meal, a more plant-based one, can significantly reduce GWP, BWF and LU. The restaurant stage, followed by the primary production, largely contributes to GWP, and food losses and waste (FLW) plays an important role, contributing significantly to all three impacts. Strategies towards energy efficiency at the restaurant, innovation in the menus, and reducing FLW are required, as well as further engagement between the HORECA sector and the academia to work in line towards sustainable eating patterns. Image 1 • An energy- and nutrient-based FU is used to assess the LCA of tapas meals. • Meals can only be environmentally compared if they have the same nutritional function. • Primary production and the restaurant stages contribute the most to GWP. • Large environmental benefits when shifting to a more plant-based tapas meal. • Reducing food losses and waste can bring large environmental benefits. [ABSTRACT FROM AUTHOR]

A large and increasing number of countries use geothermal energy as power source for domestic and industrial applications. Geothermal power plants produce energy out of this natural and renewable source in a sustainable way and contribute to reduce global warming. However, power plants effectiveness depends on the suitability of an area to geothermal energy production, which is a complex and unknown combination of many environmental factors. Nowadays, geothermal suitability assessments require invasive inspections, high costs, and legal permissions. Thus, having a global suitability map of geothermal sites as reference would be useful prior knowledge during assessments, and would help saving time and money. In this paper, the first suitability map of potential geothermal sites at global scale is presented. The map is the result of the application of data collection and preparation processes, and a Maximum Entropy model, to geospatial data potentially correlated with geothermal site suitability and geothermal plants operation. The reliability of our map is assessed against currently active and planned geothermal power plants. Our approach follows the Open Science paradigm that guarantees results reproduction and transparency, and allows stakeholders to reuse the produced standardised data, services, and Web interfaces in other experiments or to generate new maps at regional scale. Overall, our results can help scientists, industry operators, and policy makers in geothermal sites assessments. Also, our approach supports communication with citizens whose territories are involved in probing and assessments, in order to transparently inform them about the reasons driving the selection of their territory and the potential future benefits. • The first global-scale map of the suitability of an area to geothermal energy production and plant installation is presented. • Geospatial data correlated with geothermal site suitability are processed through DIVA and MaxEnt. • The reliability of the map is tested against currently active and planned geothermal power plants. • An Open Science-compliant tool is proposed to allow stakeholders to increase the map resolution and revise parameters. • This research aims at increasing the transparency of the assessment of geothermal sites. [ABSTRACT FROM AUTHOR]

It is vital for human's sustainable development to control global warming well below 2 °C compared to pre-industrial levels. In this paper, four scenarios, namely baseline (BAS) scenario, carbon capture and storage (CCS) scenario, high electricity consumption (HEC) scenario and renewable energy (REN) scenario, are developed to estimate the energy demand and carbon emission during 2020–2050 in transitional China. Furthermore, the health co-benefits of different pollutants reduction are further estimated. Our results show that the final energy demand of China will increase steadily in the BAS scenario, reaching approximately 5200 million tons of coal equivalents (tce) in 2050. While it is likely to peak around 3500 million tce in 2035 if industry and energy structure reform is actively implemented. The CO 2 emissions will stabilize at 10 billion tons in the BAS scenario. The CCS, HIG and REN scenarios can all achieve the CO 2 emission target in China with the constraints of temperature rising no more than 2 °C in 2030. Only the REN scenario, however, can achieve the 2 °C target in the medium term. Regarding health co-benefits, in 2050,102.67, 187.11 and 222.84 billion USD are gained in China under the CCS, HIG and REN scenarios, respectively, compared to the BAS scenario. Another important finding is that industry, electricity conversion and transportation sectors have the greatest health co-benefits in China, and NO x reduction plays a dominant role, which will reduce 291,000 mortality cases in the REN scenario in 2050. [ABSTRACT FROM AUTHOR]

Since 2010, as a result of the increased attention to quinoa as a highly nutritious crop and increased international demand, the acreage and production of quinoa expanded rapidly in the Andes region. Global demand and price increases create opportunities for smallholder Andean farmers but also concerns on the environmental impacts of quinoa acreage expansion and the changing quinoa production practices of smallholder farmers. In this paper, we assess the sustainability performance of smallholder quinoa production in the Junín region in the central highlands of Peru. We use primary data from a two-round survey among 367 smallholder farmers in the Junín region and secondary data from Ecoinvent and LCFoods databases. We use a combination of a life cycle assessment to assess the various environmental impacts of quinoa production; a data envelopment analysis to link the environmental performance of quinoa production with the economic performance, and quantify the eco-efficiency of individual farms; and a fractional regression model to examine the heterogeneity in eco-efficiency across farms. We find that conventional quinoa production creates a global warming potential of 7.82 kg CO 2 -equivalent per kg of protein, which is comparable to the environmental impact of organic quinoa production and production of other grain crops but much below the impact of production of rice and food from animal origin. Also, the eco-efficiency among smallholder quinoa producers is low, on average 18.2%, and that excessive use of mineral fertilizers and a switch to mechanical threshing explains this low eco-efficiency. We conclude that quinoa, with its specific nutritional characteristics, can make a contribution to a more sustainable global food production but that attention is needed to the soil fertility management practices of smallholder Andean farmers in order to reduce the environmental impact and increase the efficiency of smallholder quinoa production. [ABSTRACT FROM AUTHOR]

Community-scale composting, which can be conducted by the local council or a waste management company, is an effective starting point to divert food waste from landfill, especially for developing countries. This paper successfully demonstrates the feasibility of a community-scale food waste composting system, using the University of Nottingham Malaysia as the case study. The method selected is open-air static pile, using food waste as the substrate and leaf-litter as the bulking agent. The composting model presented in this study is also applicable to other organic wastes. The two feedstocks are mixed at a food waste-to-leaves weight ratio of 4: 1 to result in an initial moisture level of 63% and carbon-to-nitrogen ratio of 27. The composting process can be completed in 7 months, yielding about 30 wt % (on dry basis) of compost from the total organic feedstock. The finished compost is shown to meet Malaysia's organic fertiliser standard, thus demonstrating the feasibility of this low-cost technology. Economic analysis showed that substituting chemical fertilisers with the organic compost produced in-house is a viable option, and that for Malaysia, the composting system would be able to self-sustain financially only when the landfilling cost is increased 2.3 times. The life-cycle assessment showed that using composting to replace landfill for food waste, as well as substituting chemical fertilisers with the organic compost produced, can greatly reduce the environmental impacts, especially on global warming, ecotoxicity, eutrophication and fossil fuel depletion. In order to promote the widespread application of composting for organic wastes, multi-actor partnerships are essential to link governments, organisations and households in working toward a circular economy. Image 1 • A community-scale organic waste composting system is presented. • It takes 7 months to produce compost from food waste, with leaves as bulking agent. • The compost yield is 30% and its quality meets the organic fertiliser standards. • Socio-cultural, economic, environmental and technical barriers were evaluated. • This system could be replicated and scaled up easily for widespread applications. [ABSTRACT FROM AUTHOR]

This research analyzes the business feasibility of freeze-dried powdered drink mix from Thai-grown Nam Dok Mai (NDM) mango for exportation to the United States. Since food processing generates large quantities of greenhouse gas emissions which contribute to global warming, the cradle-to-grave environmental impact of the mango powdered mix, specifically global warming potential (GWP), was determined using life cycle assessment. Based on the feasibility analysis, the mango powdered mix is thus positioned as a novelty for health-conscious and environmentally-concerned consumers because the product uses NDM mango fruits of premium quality as the main ingredient and carries a carbon footprint label on the packaging. A 50 g sachet of freeze-dried NDM mango powdered drink mix is priced at USD 7.80. The financial analysis showed that the mango drink mix possesses great business potential with high profitability. The environmental impact assessment identified the freeze drying process as the dominant contributor of GWP (15.40 kgCO 2 eq) due to high electricity consumption. • This paper deals with feasibility analysis of Thai-grown mango powdered drink mix. • Cradle-to-grave global warming potential of the freeze-dried mango mix is assessed. • Freeze drying contributes the most to GWP due to high electricity consumption. [ABSTRACT FROM AUTHOR]

The wine industry is facing two major environmental challenges: consumers are increasingly aware of the impacts of wine making, and production is jeopardized by environmental changes such as global warming. Therefore, there is a growing need to measure and minimize the environmental footprint of the sector. Life cycle assessment has already proven its worth in evaluating the environmental impacts and hotspots of bottled wine production. However, the methodological discrepancies in the LCA conducted do not allow conclusions regarding the most sustainable production systems or the most significant impacts for the sector. Moreover, LCA application in the field remains scarce due to the complexity of the method and the lack of readability of its results. In this study, 10 LCA papers corresponding to 17 different products were reviewed. Methodological discrepancies have been reduced through harmonization of the functional unit, the life cycle inventory and the life cycle impact assessment method, enabling provision of a range of results for different impact categories, as well as comparisons between different wines. The LCI elements that drive the results have been identified. This can be useful to simplify the data collection and the comparability of the products in this sector. Impact clusters (indicators that follow the same behaviour and are driven by the same LCI elements) have been proposed. Three clusters of impacts ((i) climate change, fossil depletion and particulate matter formation; (ii) terrestrial ecotoxicity; (iii) agricultural land occupation) are responsible for more than 90% of the single score. Nonetheless, the proposed harmonization procedure has limitations, and no conclusion can be made on the most sustainable products due to the remaining discrepancies in the system boundaries. • A quantitative review of 10 LCA case studies of bottled wine has been conducted. • An original harmonization procedure has been proposed to compare the results of the studies. • The procedure harmonizes the goal and scope, life cycle inventories and impact assessment method. • The LCI elements and the impact driving the results have been identified. • Based on these findings, recommendations can be made to simplify the LCA of bottled wine. [ABSTRACT FROM AUTHOR]

With the frequent occurrence of global warming, acid rain, and photochemical smog, nitrogen oxide (NOx) pollution has become an increasingly serious global problem. It is essential to establish efficient approaches for seeking reasonable and practical mitigation pathways. In this paper, a NOx mitigation simulation (NMS) model is developed to facilitate the development of mitigation policies. Through constructing the NOx metabolic network, all sectors are classified according to their interactions. With production-side and consumption-side mitigation strategies adopted for different categories respectively, the changes of sectoral and system-wide indirect emissions are accounted for under the framework of urban metabolism. The results of the case study for Guangdong Province, China, illustrate that the mitigation strategies aimed at the specific sectors of the economy might not be as practical as expected. Both the type of mitigation strategies and the sector category it interferes with have a decisive influence on reduction performance. In Guangdong Province, regulating electricity, heat power generation and smelting, pressing of metals can achieve substantial reduction performance through production-based ways, and supervising the sectors with weak control and strong dependence (e.g., Construction and Other social services) is the most effective measure on the consumption side. The comprehensive mitigation strategies made from production and consumption perspectives are capable of acquiring the most efficient reduction performance. Considering cities as an ecosystem, the mitigation simulation framework established in this study has the potential to assess and formulate reduction policies of NOx emissions. • An urban NOx mitigation simulation model (NMS) is developed. • All sectors are classified according to their ecological interactions. • Different mitigation strategies are adopted for each sector category respectively. • The effectiveness of various strategies for emission reductions is evaluated. • The data analysis is conducted by MATLAB. [ABSTRACT FROM AUTHOR]