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The increasing presence of e-books (electronic books) has become a major focus in countries around the world. In the United States, e-books represented 28% of the total book sales for 2012. In Japan, the conversion from paper books to e-books is expected to accelerate by the prevalent use of smartphones and tablet PCs. It is therefore important to quantitatively evaluate the environmental load of paper books and e-books for a sustainable society. In this study, paper books are compared to e-books read on different electronic devices (e-ink tablets, tablets, cell phones, smartphones, laptop computers, desktop computers and portable music players) through a case study on a 224-page book. The study is based on key primary data such as use time and reading speed for each device and aims to minimize assumptions made in other studies. GHG emissions for paper books are 1.24 kg-CO 2 e/book, and are reduced to 1.11 kg-CO 2 e/book when the effect of paper recycling is taken into consideration. The results for e-books under average use-time conditions range from 0.25 to 0.91 kg-CO 2 e/book with the e-ink tablet having the lowest emissions. When the average use time of each e-book device is applied, the paper book has a higher impact than all the e-books. However, sensitivity analysis shows that the impact of paper books can be lower than that of e-books for larger screen devices such as tablets, laptops and desktops when the reuse of books is considered or the e-book reading device is hardly used during its life cycle. [ABSTRACT FROM AUTHOR]

Compared to cast-in-situ construction, prefabricated construction reduces the generation of construction waste; however, construction waste cannot be entirely eliminated through prefabrication and can be generated at each stage of its life cycle. This paper generates a system dynamics model, comprising two causal-loop diagrams and one stock-flow diagram, to simulate the effectiveness of policies on decarbonizing prefabricated concrete building waste. The model can predict the annual and total construction waste, along with the associated carbon emissions, under different policy scenarios in China by 2030. This paper focuses on prefabricated concrete buildings in China, with specific attention to the wastage of concrete, bricks, mortar, and metal. In single-factor scenario simulations, increasing landfilling fee is the most effective policy for waste decarbonization, potentially reducing carbon emissions by 31%. Increasing prefabrication rate and enhancing regulation degree at the design phase of prefabrication can directly reduce prefabricated building waste generation, subsequently resulting in an 18% and 7% carbon emissions reduction. Multi-factor scenario simulations demonstrate that the simultaneous application of all four policies is most effective, achieving a 44% reduction in carbon emissions. This research establishes a theoretical framework for prefabricated concrete building waste management and provides the Chinese government with practical insights on optimizing policies for waste decarbonization in the dynamic landscape of prefabrication. • This paper develops the prefabricated building waste generation and disposal systems. • The model predicts the construction waste and associated carbon emissions by 2030. • Raising landfill fee is an effective policy for decarbonizing construction waste by 31.06%. • Prefabrication rate reaching 100% can reduce 18.04% of carbon emissions from waste. • Applying all policies is most effective, achieving a 44.34% carbon emissions reduction. [ABSTRACT FROM AUTHOR]

As a significant source of carbon emissions, road logistics operators are under increasing pressure from governments and customers to find ways to decarbonize as part of broader global efforts to reach net zero. Decarbonization of road logistics relies on the widespread diffusion of existing and emerging technological transport solutions. These include alternative fuel vehicles, battery technologies, renewable energy and charging solutions. All promise to reduce carbon emissions, but their implementation remains challenging, expensive, and risky. As early adopters of alternative fuel vehicles have reported, transitioning from fossil fuels poses challenges that must be prepared for and understood to minimize the obstacles to genuine emissions reductions in road logistics. A considerable volume of academic research has been published advocating emission reduction solutions and providing detailed analyses of their potential positive environmental impacts. However, to our knowledge, no frameworks integrate these analyses with practical insights into current and anticipated challenges for road logistics operators transitioning from fossil fuels to a decarbonized future. This paper analyses contemporary evidence and insights on current and future issues and presents an integrated framework for road freight logistics decarbonization challenges. The framework primarily focuses on decarbonization through alternative fuels and analyses three categories of challenges from socio-technical, economic, and environmental perspectives. The three categories of challenges relate to alternative fuel vehicles and fleets, alternative fuel distribution infrastructure and renewable energy generation. The underlying principle of the framework is to provide a practical tool that supports a more informed view of both the advantages and challenges of transitioning to alternative fuels. This research contributes to the body of knowledge by providing a framework to help direct future research into tackling these logistics decarbonization challenges. The insights presented in this paper may also inform practitioners by sensitizing them to potential roadblocks in the transition away from fossil fuels. • Framework integrating road freight logistics decarbonization challenges. • Analyse alternative fuels, alternative fuel distribution and renewable energy. • Three perspectives on decarbonization: socio-technical, economic, and environmental. • Highlight logistics services provider strategies to minimize risk and uncertainty. [ABSTRACT FROM AUTHOR]

As agriculture is an important contributor to greenhouse gas emissions, carbon labelling aiming at climate protection will play an increasing role in the future. An important example is the development of guidelines and standards for climate-neutral agricultural products and their respective certification. Carbon neutral certifications are, however, affected by criticism and mistrust as there were cases of doubtful claims to carbon neutrality in the past. Against this background, this paper analyses a rather promising case of certification for carbon neutrality: the pioneer case of the Costa Rican coffee cooperative Coopedota, which is the first organization worldwide that achieved certification for carbon neutrality in coffee using a renowned international standard. Coopedota's carbon neutral coffee is certified according to the Publicly Available Specification (PAS) 2060, which is based on a Life Cycle Assessment (LCA). The paper analyses how the cooperative came to apply this certification, which challenges it faced and how the cooperative solved them. Furthermore, the paper examines the social, political and institutional factors that fostered this innovation. To analyse the success factors that were relevant in this case, a Social Network Analysis approach was used. An innovative tool called ‘Process Net-Map’ was applied to visualize the social networks that enabled the actors to pursue the certification scheme. Process Net-Map also made it possible to identify the role and importance of different types of actors. The analysis shows that the certification created awareness on emission hot-spots along the coffee value chain. Reliable farm data from producers were identified as crucial because emissions at the farm level account for 60% of total emissions. It was also found that by avoiding pure offsetting, PAS 2060 supports emission reduction; however, PAS 2060 does not account for on-site carbon sequestration, for which coffee cultivation has high potential. Overall, the study found that the most important success factors include a combination of (i) past achievements in Coopedota's sustainability policy, which was incentivised by national and international trends and (ii) strong, visionary actors who performed the necessary network functions. The analysis also showed that the network of relevant actors is highly centralized, (indicated by a degree centrality of 86%), which may jeopardize the sustainability of the innovation project. Moreover, the network analysis revealed the importance of ‘double linkages’ between actors, which points to the role that combined services, such as funding and advice, played for the introduction of the certification scheme. General implications are derived from this case for future efforts to promote carbon neutral certification schemes for agri-food products. [ABSTRACT FROM AUTHOR]

Decarbonisation of stationary energy supply, particularly electricity grids, is the current focus of climate change mitigation policy. However, studies have suggested that this narrow policy focus is insufficient to achieve meaningful global emissions reductions. Using Iceland as a case study, this paper demonstrates that significant emissions arise from transport and imported products, which are often not fully captured in territorial GHG inventories. This results in high greenhouse gas emissions per capita regardless of the nation's domestic energy supply. The result is a low carbon illusion in which rich economies believe they are reducing their GHG responsibility whilst global emissions continue to grow. This paper presents the first consumption-based carbon footprint (CBCF) analysis for Iceland, a nation where the stationary energy supply is 99% renewable, and could be viewed as a decarbonisation ‘future case’ for rich nations globally. The study combines Icelandic household expenditure data with the Multi-Regional Input-Output database Eora to calculate the CBCF of Icelandic households. The average annual CBCF of Icelandic households was 10.4 tCO 2 eq/capita, similar in magnitude to other EU nations despite Iceland's unique energy supply. GHG emissions from transport, food and goods dominated the household CBCF. The national CBCF was higher than most European nations and 55% higher than the territorial emissions inventory. Approximately 71% of household emissions were attributed to imported goods, which were mapped globally revealing that the GHG emissions burden of Icelandic consumption falls primarily on developing nations. The findings suggest that a broader GHG accounting framework and resulting policy focus is required, both in Iceland and globally, that incorporates both supply and demand-based GHG reduction strategies. [ABSTRACT FROM AUTHOR]

Evaluating innovative process technologies has become highly important within the last decades. As standard tools different Life Cycle Assessment methods have been established, which are continuously improved. While those are designed for evaluating single processes they run into difficulties when it comes to assessing environmental impacts of process innovations at macroeconomic level. In this paper we develop a multi-step evaluation framework building on multi regional input–output data that allows estimating macroeconomic impacts of new process technologies, considering the network characteristics of the global economy. Our procedure is as follows: i) we measure differences in material usage of process alternatives, ii) we identify where the standard processes are located within economic networks and virtually replace those by innovative process technologies, iii) we account for changes within economic systems and evaluate impacts on emissions. Within this paper we exemplarily apply the methodology to two recently developed innovative technologies: longitudinal large diameter steel pipe welding and turning of high-temperature resistant materials. While we find the macroeconomic impacts of very specific process innovations to be small, its conclusions can significantly differ from traditional process based approaches. Furthermore, information gained from the methodology provides relevant additional insights for decision makers extending the picture gained from traditional process life cycle assessment. [ABSTRACT FROM AUTHOR]

The cement industry is generally considered responsible for upwards of 5% of anthropogenic greenhouse gas emissions. This is a result of the high energy intensity of the process, significant CO 2 release from the raw materials used, and large global consumption. It is also a high growth sector as emerging economies develop their infrastructure. This paper outlines an investigation into day-to-day performance variation that, if scaled to the global level, represents a potential for improvement of up to 100 Mt CO 2 equivalent per year. Optimising this operational variation is not included in current roadmaps for reduction of cement industry CO 2 emissions, and has the potential to be cost neutral, or even save money for cement producing companies. The paper analyses a case study of a plant in the UK, operating a pre-calciner type kiln commissioned in 1986. Production data was analysed to examine the day-to-day variation in the fuel-derived CO 2 emissions, in order to estimate the potential for operational improvement. Various factors were then analysed to determine what drives this potential improvement, including fuel mix, rate of production, and process airflow. The day-to-day performance of the plant, as measured by the fuel-derived CO 2 emissions per tonne of clinker produced, varied significantly. (Clinker is the material ground and mixed with ∼3% gypsum to produce cement). Improvement of the plant to 10th percentile best observed performance levels would represent a 10% drop in CO 2 emissions and a 7% drop in energy consumption, with associated cost savings. Two mathematical models were used, first to examine the energy balance of the plant and then to predict CO 2 emissions from given input conditions. The largest source of energy consumption was the dissociation energy required to form clinker, however, the variation in this was small. Airflow and fuel type were found to dominate the variation of performance. Optimising the factors affecting performance was predicted to reduce energy consumption by 8.5% and CO 2 emissions by 19.5%. The paper concludes that there exists significant opportunity to reduce the emissions from cement plants by operational means, and that fuel mix and excess air ratio should be the focus of future research. [ABSTRACT FROM AUTHOR]

The quest for sustainability and reduction of human impact on the planet has led to discussions about environmental efficiency in the manufacture and use of automotive vehicles. The advancement of environmental and government laws has encouraged the automotive industry to seek constant improvements in safety, fuel economy and reduction of greenhouse gas emissions. To achieve these goals, reducing the weight of vehicles has been considered a relevant strategy, with several research and development efforts in search of high-tech materials and innovative design. The assessment of the life cycle of vehicles, from the extraction of raw materials to the end of their useful life, is essential for estimating environmental impacts. In this context, this paper focuses on the life cycle analysis of vehicles with new generation steel structures (Body in White Solution) compared to current steels (Body in White Baseline), aiming at reducing greenhouse gas emissions by reducing of the thickness of the steel plates, maintaining the mechanical properties necessary to guarantee the safety of the vehicle. The methodology of this study was divided into the evaluation of Body in White (BIW) mass in current steels (Baseline) and in advanced high resistance steels (Solution); detailing the vehicular life cycle from the extraction of materials to its end of life; in the estimation of greenhouse gas emissions through simulation and in the comparison of vehicle emissions with BIW in current steels and in advanced high resistance steels. As a result, it was possible to observe that, in the comparison of the CO 2 footprint, modeled in the Eco Audit, there is a 15% reduction in emissions in the CO 2 footprint for the BIW solution, as well as a 7% reduction in the C eq total , in the on-site test and a saving of 260.40 L in fuel consumption, that is, the reduction in vehicle weight plays a significant role in reducing CO 2 emissions, providing a mitigation factor for global warming. [Display omitted] • There is a 15% reduction in emissions in the CO2 footprint for the BIW solution. • There is a 7% reduction in the Ceq total, in the on-site test. • Reduction in vehicle weight plays a significant role in reducing CO2 emissions. • Providing a mitigation factor for global warming. • There is a fuel economy of 260.4 L over the vehicle's life cycle. [ABSTRACT FROM AUTHOR]

The construction sector is one of the main contributors to carbon dioxide (CO 2) emission and causes of global warming. CO 2 mitigation solutions are vital. New technologies can facilitate and improve these efforts. Thus, the paper reviews how new technologies of artificial intelligence and machine learning have contributed to CO 2 emissions reduction in construction and what techniques have been applied in the literature to provide significant information that will be beneficial for the construction sector design and management. The paper provides the results of a content review, including their contributions and gaps. A total of 78 papers were identified to develop the dataset. The method was a combination of systematic reviews, including co-occurrence analytical map development of the main keywords, co-authorship network analyses, publication source analyses, and content analysis, including theme identification and review of the selected papers, which were divided into five conceptual clusters based on their scopes: (1) sustainable materials and components design/production, (2) on-site vehicles and equipment, (3) energy and life cycle assessment, (4) optimization, decision-making and solution-based platforms, and (5) real-world monitoring. The content of each cluster of papers was also reviewed, and the potential gaps were identified and discussed. A set of directions for future research investigations were presented that can be a valuable source for researchers in their future research. This paper contributes to the current knowledge base by presenting insights into intelligent techniques in the construction industry to mitigate CO 2 emissions. [ABSTRACT FROM AUTHOR]

Buildings are responsible for more than 40% of global energy usage and as much as 33% of global greenhouse gas emissions in both developed and developing countries. However, the study of carbon emissions over a building's life cycle based on Ecotect and building information modeling in developing areas of Nanjing has yet to be conducted. Therefore, the results and recommendations of this paper represent a contribution to the literature on this topic. The scientific value of this paper is that Ecotect and building information modeling can be helpful in simplifying the estimation of carbon emissions over a building's life cycle because they can provide a majority of the information and calculation tools necessary for performing an life cycle assessment (LCA), which may alleviate the problem of insufficient information when executing an LCA of a building. A sensitivity analysis was performed by changing several parameters to identify the parameters that have the largest impacts on the performance a building. A comparison of the life cycle carbon emissions for each stage showed that the operational stage is the largest contributor to carbon emissions. Approximately 85.4% of the total carbon emissions were generated during operation. The construction stage accounted for 12.6% of the total carbon emissions. Approximately 2% of the total carbon emissions occurred during the demolition stage. Compared to the total carbon emissions over the entire life cycle of the building, carbon sequestration by vegetation was minimal. Thus, these findings indicate that governments can achieve the greatest reductions in carbon emissions by targeting the operational phase of buildings. However, the opportunity for addressing non-operational phases should not be ignored because the average carbon emissions per working area per year of non-operational stages are far greater than those of the use phase. [ABSTRACT FROM AUTHOR]

The significant carbon emissions generated by China's sludge treatment industry cannot be ignored. However, with only a few recent well-executed studies on carbon emission reduction in the sludge treatment field, the literature awaits a more comprehensive assessment and prediction whether the sludge treatment industry can achieve the dual-carbon target. This article aims to fill this gap, holistically examining the carbon emission reduction potential in the industry. Using the moving average method and IPCC method, the projected carbon emission value of sludge treatment in China from 2021 to 2030 indicates a total net carbon emission of 0.3 million tons by 2030. This suggests that the sludge treatment industry is on track to meet the carbon peak target, leaving surplus carbon quotas or credits available to assist other industries for carbon emissions reductions. The study also finds that only incineration and composting demonstrate the potential to be able to partially offset carbon emissions through resource utilization in certain stages or processes. Therefore, the current sludge treatment methods do not yield comprehensive emission reduction effects and cannot provide sufficient contribution to China's dual carbon goals. To address this issue, the paper explores a new scheme that focuses on improving the sludge treatment process. The scheme comparative analysis reveals that, even with all sludge treatment methods optimized, the total net carbon emissions of the industry could only be reduced to 0.058 million tons. This reduction falls short of significantly mitigating carbon emissions to achieve the carbon neutrality goal. Therefore, industries unable to achieve substantial net carbon reduction may need to explore alternative measures, such as carbon sinks, to ultimately attain carbon neutrality. [ABSTRACT FROM AUTHOR]

Towards the target of carbon neutrality, the need for deep decarbonization in iron and steel industry is increasingly recognized. Existing studies rarely mention the effects of collaboration with its source industries for carbon emission reduction in ISI. Furthermore, the fundamental laws of CO 2 emission reduction capacity with cost change of source substitutions for various steel production routes under market economics are unclear. To avoid the blind substitution of clean sources for meeting the urgent requirements for decarbonization in China's steel industry, which may result in increased carbon emissions and uneconomical carbon reduction from a lifecycle perspective. This paper integrates the production and utilization processes of source resources into the steel production process, establishes coupling models of carbon and value flows for four main types of steel production routes, and aims to quantitatively analyze the specific CO 2 emission reduction potential and costs. Three economic market development scenarios from 2021 to 2060 are set, and the marginal carbon prices of various source substitutions are determined. Subsequently, decarbonization pathways with the goal of minimizing production costs are developed. Finally. The future resource demand and the carbon emission reduction contributions of source industries collaborated are predicted. The results show that (1) about 81.7–89.9 % of CO 2 emissions could be reduced in the scenarios; (2) the demands of electric power and hydrogen energy will reach 54.48–511.90 BkWh and 7.47–10.31 Gt in 2060, respectively; and (3) collaboration with source industries could make 18.3–18.3% of CO 2 emission reduction contributions. All in all, this study could provide scientific support for the low-carbon transformation of China's steel industry. • Carbon and value flows of BF-BOF, Scrap-EAF, DRI-EAF, MOE-EAF routes are analyzed. • CO 2 emission reduction potential with marginal carbon price is determined. • Decarbonization paths during 2021–2060 for China's steel industry are developed. • Quantify the contribution of collaborative carbon reduction with source industries. [ABSTRACT FROM AUTHOR]

Forecasting the future emission trajectories and the relating sensitive driving factors of emissions for cities is of great significance to formulate realizable CO 2 mitigation policies. To proceed the forecasting, studies on peak prediction and quantification of reduction potential at the city level are essential. However, the studies in the area are very limited. Selecting the Beijing-Tianjin-Hebei urban agglomeration (BTH) as the study region, this paper aims to contribute to the research area and provides implications for other cities or urban agglomerations. The Kaya identity and multi-scenario simulation were employed to predict the dynamic evolution pathways of CO 2 emissions from 2021 to 2035 and explore the differential CO 2 peak time, peak value, and reduction potential for 13 cities in BTH. Monte Carlo simulation, Mann-Kendall trend test and Sen's slope estimation method are jointly used to reduce uncertainties in estimation. The Monte Carlo simulation results show that most cities in BTH have already reached their CO 2 emissions peak, while Tianjin, Langfang, Cangzhou and Tangshan are expected to reach their peaks between 2025 and 2030. Among them, 5 and 8 cities have the risk of not reaching their peak before 2035 in the high consumption scenario (HCS) and extensive development scenario (EDS) respectively. Comparative analysis reveals that low-carbon scenario (LCS) and sustainable development scenario (SDS) have significant effects on emissions reductions. The top three cities in terms of accumulative emission reduction in 2021–2035 are Tianjin, Tangshan and Cangzhou, estimated as 117.82–250.75 Mt CO 2 in LCS and 217.77–454.10 Mt CO 2 in SDS, respectively. The results of sensitivity analysis reveal that the most critical driver of CO 2 emissions in Beijing is population, while that is GDP per capita for Tianjin. Langfang and Hengshui showed the highest sensitivity to energy intensity. Accordingly, these cities have differentiated concerns and priorities to achieve their carbon peak goal as scheduled. • Kaya identity and scenario simulation are combined to predict future CO 2 emissions. • The BTH would reach CO 2 emission peak by 2025, but the time varies on city-level. • Tangshan, Langfang, and Cangzhou are at greater risk of not reaching the peak by 2030. • Tianjin, Tangshan and Cangzhou have the greatest potential to reduce emissions. • Differentiated priorities are suggested for specific city's CO 2 mitigation targets. [ABSTRACT FROM AUTHOR]

In this letter, we respond to the articles “Decoupling global environmental pressure and economic growth: scenarios for energy use, materials use and carbon emissions” by Heinz Schandl et al. (Journal of Cleaner Production, 132, 45–56) and “Australia is ‘free to choose’ economic growth and falling environmental pressures” by Hatfield-Dodds et al. (Nature, 527, 49–53). The authors of these papers suggest that policy settings are crucial for Australia to allow growing standard of living to coincide with lower environmental pressure and impact. Both papers make it clear that decoupling has not occurred in past, but stress that this does not mean it cannot occur in the future. Here, we undertake a comprehensive trend analysis by putting their decoupling scenarios into a historical context to assess the feasibility of decoupling economic growth from environmental impacts. To this end, we undertake a structural decomposition analysis to examine the drivers of a change in Australia's greenhouse gas emissions from 1976 to 2050. Using the well-known I = PAT equation, we appraise the contribution of population growth, affluence and technology in accelerating or decelerating the growth of emissions over the 75 year period. Our results suggest that population growth and affluence are key accelerators of greenhouse gas emissions. We argue that in order to decrease emissions from fuel consumption, unprecedented improvements in emissions intensity will be required both in Australia and globally. [ABSTRACT FROM AUTHOR]

Abstract Whilst higher education institutions are often being referred as sustainability change agents, employees of such organizations have an essential role towards promoting low-carbon practices amongst students, who are also influenced by the attitudes and behaviours of teachers. For this, employees of higher education institutions need to properly understand their personal carbon emissions along with reduction mechanisms, in order to instil such knowledge and skills to students. However, previous studies focused principally on estimating carbon emissions of higher education institutions to set reduction targets, rather than emphasizing on the human factor related to reduction of greenhouse gases. Furthermore, limited studies have been undertaken to estimate the carbon footprint of employees of higher education institutions. Taking cognizance of these gaps, this paper investigates the perceptions and behaviour pertaining to personal carbon emissions of employees of higher education institutions through answering different research questions, in order to conceptualize a carbon management framework. To achieve this purpose, a survey was conducted in different higher education institutions in Mauritius and involved 440 employees. Results revealed that carbon emissions of this target group are influenced by demographic factors and nature of activities. In addition, the average carbon footprint of participating employees was found to be approximately two times higher than the per-capita carbon footprint of the inhabitants of the island. These findings also mean that more efforts are needed at different levels in order to better engage employees of higher education institutions to reduce their personal carbon footprints. For this, a carbon management framework has been proposed in this study. Highlights • Studies perceptions and behaviour of employees of HEIs on personal carbon emissions. • Analyses motivations and barriers for employees of HEIs to reduce carbon emissions. • Provides quantitative results on personal carbon emissions of employees of HEIs. • Proposes a carbon management framework to help employees reduce personal emissions. [ABSTRACT FROM AUTHOR]

Greenhouse gas (GHG) emissions from electricity generation are generally assessed using a yearly average carbon intensity (in carbon dioxide equivalent emissions per unit of energy). This masks the variability of emissions associated with different forms of generation over different timescales. Variability is a characteristic of electricity systems with high levels of renewable generation, where fossil fuels are typically used to meet any shortfall in supply. In this paper we argue that quantification of the time variability of carbon intensity is necessary to understand the detailed patterns of carbon emissions in electricity systems, particularly as future systems are likely to increasingly rely on a mix of time-variable generation types such as wind, hydro and solar. We analysed the time-varying carbon intensity of New Zealand's electricity sector, which has approximately 80% renewable generation. In contrast to many other nations, we found that carbon intensity did not consistently follow daily peak demand, and was only weakly correlated with demand. This result, and the finding that carbon intensity has significant seasonal variation, stems from the dominance of hydro (albeit with limited storage capacity) in New Zealand's generation mix. Further investigation of the operating regimes of the fossil fuel generators, using time-varying analysis, indicates that New Zealand's electricity system is sub-optimal from a GHG emission perspective, with more coal generation than would seem to be required. Two policy measures, which also generalize to other countries, are proposed to address this issue: (i) the creation of an electricity capacity market – providing revenue for standby fossil fuel generation capacity without the need for continual generation; (ii) use of time-varying carbon intensity to inform demand-side measures and decisions about new renewable generation. [ABSTRACT FROM AUTHOR]

Carbon dioxide (CO 2 ) emissions have become a rising concern in China. Few studies have considered spatial correlation and agglomeration effect of CO 2 emissions for adjacent regions and provinces. This paper employs Geographical Weighted Regression (GWR) model to examine the impact of urbanization, industrial structure and energy intensity on CO 2 emissions and reveals the spatial correlation in different provinces in 2005, 2008, 2011 and 2015. The results indicate that there is an obvious spatial effect on CO 2 emissions of each province based on the GWR results. Urbanization is the most significant factor in the increase of CO 2 emissions for all provinces in each year. For the neighboring provinces, a coordinated low-carbon urban construction plan should be carried out based on the urbanization development level. Energy intensity has a positive effect on CO 2 emissions, but the effect on the emission reduction is relatively weak and unstable. It should strengthen exchanges and cooperation between provinces and regions by jointly exploring and promoting technologies to improve the efficiency of resource use and reduce CO 2 emissions. The influence of industrial structure on CO 2 emissions is positive, indicating that the industrial structure adjustment plays an important role in carbon emission reduction. [ABSTRACT FROM AUTHOR]

As greenhouse gas emissions are a key driver of climate change, sources of CO 2 must be mitigated, particularly from carbon-intensive sectors, like power production. Natural gas provides an increasingly large percentage of electricity; however its lower carbon intensity is insufficient to make proportional reduction contributions to circumvent 2 °C global warming. The low partial pressure of CO 2 in its flue gas makes post-combustion capture more challenging – increasing the CO 2 in the exhaust assists in enhancing capture efficiency. This paper experimentally investigates the impact of the combination of humidified air turbines and exhaust gas recirculation to increase CO 2 partial pressures, with the aim of evaluating their effects on emissions and turbine parameters at various turndown ratios. It was found that CO 2 levels could be increased from 1.5 to 5.3 vol%, meaning more efficient post-combustion capture would be possible. CO 2 and steam additions increased incomplete combustion when used together at high levels for low turndown ratios (below 60%), with CO increasing from 49 to 211 ppm and CH 4 from 2.5 to 52 ppm; this effect was negated at higher power outputs. Turbine cycle humidification resulted in net improvements to the turbine efficiency, by up to 5.5% on a specific fuel consumption basis. [ABSTRACT FROM AUTHOR]

Cities can play a key role in the low-carbon transition, with an increasing number of cities engaging in carbon mitigation actions. The literature on urban low-carbon transition shows that low-carbon urban development is an inevitable trend of urban sustainable future; there is a great potential albeit with some limitations for cities to reduce its carbon footprints, and there are diverse pathways for cities to achieve low-carbon development. There is, however, a limited understanding in terms of the internal mechanism of urban low-carbon transition, especially in rapidly developing economies. This paper attempts to address this gap. We examine how low-carbon policies emerge and evolve, and what are the enabling mechanisms, taking Shanghai as a case study. We developed an analytical framework drawing on system innovation theory and sustainability experiments for this purpose. A total of 186 relevant policies were selected and analyzed, which is supplemented by the interviews with stakeholders in the government to gain a deeper insight into the policy contexts in Shanghai. We found that the city's low-carbon initiatives are embedded and integrated into its existing policy frameworks. A strong vertical linkage between the central and the local governments, and more importantly, a nested structure for innovative policy practices were identified, where a top-down design is met with bottom-up innovation and proactive adoption of enabling mechanism. The structure includes two layers of experiments that facilitate learning through policy experiments across scales. The uniqueness, effectiveness, applicability and limitations of these efforts are discussed. The findings provide new theoretical and empirical insights into the multilevel governance of low-carbon transition in cities. [ABSTRACT FROM AUTHOR]

Reducing CO 2 emissions has become a major and urgent environmental goal worldwide. In this paper, we sample the data of 41 regions (including 165 countries) from 2000 to 2014 and adopt a gravity model to obtain an overview of the global flows of CO 2 emissions, energy consumption, the global economy and capital stock since the beginning of the 21st century. We then investigate global technical efficiency, reduction potential, shadow prices and factors influencing the marginal abatement costs of CO 2 emissions based on a quadratic directional output distance function. The empirical results show the following: (1) the global centres of gravity for CO 2 emissions, energy consumption and capital stock have accelerated their shift to the Asian inland in the 21st century, but the global centre of gravity for the economy did not show the same trend. (2) Global technical inefficiency demonstrates a U-shape, with a turning point in 2007. Average annual total global CO 2 emissions could be reduced by 4482.28 Mt, and the global marginal abatement costs of CO 2 emissions are approximately 673.74–697.73 USD/t. (3) The relationship between economic development and marginal abatement costs is represented by a U-shaped curve. The world is currently in the climbing phase of this curve, implying that controlling CO 2 emissions is becoming more costly. Moreover, energy structure, industrial structure, and CO 2 emissions are negatively correlated with marginal abatement costs. Finally, the financial crisis has had a significant effect on marginal abatement costs. [ABSTRACT FROM AUTHOR]

With the accelerating pace of urbanisation around the world, the planning, development and operation of buildings and precincts have become increasingly important with respect to energy use and the associated carbon footprint of the modern built environment. Over recent decades, much effort, both in research and in practice, has been devoted to building construction and urban planning for the improvement of energy efficiency and greenhouse gas emissions. However, the accuracy of modelling and evaluation of energy and carbon performance for buildings and urban precincts remains limited, affected by inadequate energy intensity data and highly integrated building systems, as well as the complex interactions between buildings and the urban eco-system. This paper presents a critical review of current measures and models for representing and assessing life cycle energy as well as associated emissions profiles at both the building and the precinct levels. It also identifies influential factors and explores interactions among buildings, surrounding environment and user behaviours at the urban precinct level by taking a systems perspective. Based on such a review, this study maps out some key challenges for integrating energy and carbon metrics, and finally proposes a precinct-level system boundary definition and an integrated model following systems thinking. The proposed model can facilitate a critical thinking approach about the evaluations of global energy and emissions, and support the quantification of energy consumption and associated emissions for building precinct systems. [ABSTRACT FROM AUTHOR]

Forecasting CO 2 emissions in China always has been of great significance as it could help the government to improve energy policies and plans. To this end, a novel grey multivariable model is designed in this paper. Compared with the conventional grey multivariable model, which has certain drawbacks of inaccurate prediction and poor adaptability that restrict their applications in practical cases, the proposed model can make three improvements: first, an optimized grey model having a modified background value is proposed to predict the trends of the driving variables. Second, the novel grey multivariable model is established, combined with the changing trends of driving variables. Third, the adjustment coefficient in the new model is optimized to obtain optimal values for the time response function. To demonstrate its efficacy, the proposed model is employed to reproduce and predict the CO 2 emissions from fuel combustion compared with four benchmark models—the results show that the new model yields more accurate forecasting results than the competing models. Eventually, the new model will be used to quantify future Chinese CO 2 emissions from fuel combustion from 2014 to 2020, and the forecasted results can provide a solid basis for formulating environmental policies and energy consumption plans. [ABSTRACT FROM AUTHOR]

Greenhouse gases remain as threat to the environment. Various models employed in greenhouse gases are either to determine the causative factors responsible for emission, forecast emission or to optimize. Integrating these models would reduce the limitations of individual models to better assess possible greenhouse mitigation. This paper addresses the management technique for analyzing, assessing and mitigating industry's carbon dioxide (CO 2 ) emission. The current work offers a different technique based on an integrated model utilizing the functions of Index Decomposition Analysis (IDA), Artificial Neural Network (ANN) and Data Envelopment Analysis (DEA) composed of activity, structure, intensity and energy-mix as inputs responsible for CO 2 emission. By considering how the three different models are integrated into one system, it will be demonstrated how much percentage of an industry's CO 2 can be reduced. The Canadian industrial sector was analyzed using the integrated model and it was discovered that 3.13% of emitted CO 2 from year 1991 to year 2035 could be mitigated. [ABSTRACT FROM AUTHOR]

Construction management in China has embraced a new practice encompassing the evaluation criteria of green construction. Thus, greenhouse gas emissions produced during the construction period should not be overlooked anymore. The greenhouse gas emissions from construction projects are evaluated based on life cycle assessment theory, and on green construction evaluation and management techniques. A procedure for assessing the greenhouse gas emissions from construction projects is developed using the unit construction process, and by classifying and integrating the different components of construction projects. A segregation-integration method was established for calculating the greenhouse gas emissions of construction project. A mathematical model and framework to calculate the greenhouse gas emissions from construction projects have been established. The energy consumption and carbon dioxide emissions for earthwork, foundation work, masonry, and reinforced concrete during construction are calculated based on the example of a commercial building in a large-scale residential complex in the Pingshan New District of Shenzhen City. The greenhouse gas emissions were calculated as equivalent carbon dioxide emissions. High-rise buildings and villas have the highest unit carbon emissions of 54.51 kg/m 2 , and account for 84% of the carbon dioxide emissions produced during the construction of the residential community. The unit carbon emissions for construction of the entire residential community are approximately 54.18 kg/m 2 . The scientific value of this paper is that the carbon emissions during the construction stage of a residential community were quantitatively assessed. The unit carbon emissions of the buildings during construction can be used to calculate unit energy consumption of buildings during construction, which should be useful in realising energy savings, and can therefore provide management guidance for reducing energy consumption during the life cycle of building, especially consumption during construction. [ABSTRACT FROM AUTHOR]

To achieve the goal of carbon emission reduction, a number of countries have implemented carbon tax policies, and carbon pricing has become an important tool. This paper discusses the interactions between a government and an enterprise for implementing carbon taxes over time or by level of tax, considering greenhouse gas emission. We examine the impacts of various carbon tax policies on enterprises' investments in new technology, their reductions in production quantity, and governments' tax remittances. A case study of the strategic responses of three firms in Taiwan's electronics, cement, and steel industries to two carbon emission policies promulgated by government shows that appropriate levels of tax can induce an enterprise to alter its production processes to achieve emission reduction as part of a long-term business strategy. [ABSTRACT FROM AUTHOR]

Despite considerable mitigation efforts, global emissions from the electricity sector continued to grow in recent years. In Australia, the electricity sector is the largest CO 2 -emitting industry, contributing 35% of the country's total greenhouse gas emissions. The Australian government targets an 80% reduction of greenhouse gas emissions by 2050 relative to 2010. With a large variety and quantity of renewable energy resources, it is technically feasible and seems indispensable that Australia's electricity sector be largely decarbonised by 2050 in order to achieve this target. In this paper, scenario-based hybrid Life-Cycle Assessment is applied to calculate the economy-wide carbon footprints of seven electricity generation technologies in scenarios with differing renewable electricity penetration. This work is the first to apply a full life-cycle approach to scenario analysis of electricity generation in Australia. The findings are at the higher end of previously reported carbon footprint intensity ranges and above median values. However, even when taking into account indirect emissions along the technologies' life-cycles, the results indicate that the employment of different renewable energy technologies can potentially save a considerable fraction of Australia's greenhouse gas emissions. This makes renewables an essential option for climate change mitigation. [ABSTRACT FROM AUTHOR]

To reduce GreenHouse Gas (GHG) emissions, the Kyoto Protocol identifies a number of activities that are closely related to land use, included in the category called Agriculture, Forestry and Land Uses (AFOLU). While forests and agricultural systems result in CO 2 absorptions (live biomass, dead biomass and soil), every process undertaken for their management requires energy and resources, which can lead to a significant reduction of the environmental benefits. The study analyzes three tree plantations managed at different cultivation intensities in Italy, from an extensively managed plantation (a pure oak plantation) and a semi-intensively managed plantation (walnut and poplar plantation with nurse plants), to an intensively managed olive grove. Permanent and non-permanent biomass were accounted for in order to get the carbon stock of every plantation, estimated at the same age of 14 years old. The numerous processes operated for management of different cultivated species, e.g. planting, soil management, fertilization, phytosanitary treatments, pruning, harvesting, etc. were monitored and their impacts were quantified by applying the methodology known as Life Cycle Assessment (LCA). Removals (carbon sequestrations) were compared to emissions on a time scale, in order to assess the net CO 2-eq balance. Impacting treatments and processes were identified and further analysis on the individual phases and materials were conducted. Olive trees showed an unexpected capacity to store CO 2-eq , but this ability was evident only if annually harvested fruits and prunings were considered in the calculation. The plantation that demonstrated its ability to store most CO 2-eq at the age of 14 was the semi-intensively managed plantation, showing a higher efficiency in the energy spent by man. The paper offers a contribution for an innovative environmental performance evaluation of different tree cultivation management systems, including the assessment of potential benefits in terms of sequestered CO 2-eq for the studied tree plantations and possible avoided emissions thanks to sustainable agricultural practices. [ABSTRACT FROM AUTHOR]

Energy system modeling is highly relevant to support policymakers in defining strategies to achieve the European Green Deal targets towards carbon neutrality in 2050. Therefore, marginal CO 2 abatement cost curves are widely used in climate policy to assess the relationship between total cost changes and CO 2 emission reductions. Various methods exist for deriving abatement cost curves, leading to different results and policy implications. Most model-based methods derive smooth curves that can be transformed into step-wise curves through decomposition analysis, lacking system interactions at high temporal, sectoral, and techno-economic resolution. This paper overcomes these limitations by presenting a linear optimization approach with an hourly resolution to derive step-wise marginal CO 2 abatement cost curves for the German sector-coupled power system in 2030. Next to methodological insights, results indicate that early adoption of vehicle-to-grid ensures faster photovoltaic rooftop integration by reducing CO 2 abatement costs. Further, vehicle-to-grid replaces storage systems and decreases electricity generation costs while having no impact on CO 2 abatement costs of ground-mounted photovoltaic and onshore wind. Additionally, results show a high level of techno-economical detail and the least-cost sequential order of an optimal technology portfolio, allowing policymakers to formulate appropriate measures to achieve decarbonization targets. • A linear optimization model derives step-wise marginal CO 2 abatement cost curves. • Results show interdependencies and substitution effects of decarbonization measures. • Hourly sector-coupling analysis is performed for the German energy system in 2030. • Early VtG adoption ensures PV rooftop integration by reducing CO 2 abatement costs. • VtG replaces storage and decreases short-term electricity generation costs. [ABSTRACT FROM AUTHOR]

Greenhouse gas (GHG) emissions are simultaneously exhausting the world's supply of fossil fuels and threatening the global climate. In many developing countries, significant improvement in living standards in recent years due to the accelerating development of their economies has resulted in a disproportionate increase in household energy consumption. Therefore, a major reduction in household carbon emissions (HCEs) is essential if global carbon reduction targets are to be met. To do this, major Organisation for Economic Co-operation and Development (OECD) states have already implemented policies to alleviate the negative environmental effects of household behaviors and less carbon-intensive technologies are also proposed to promote energy efficiency and reduce carbon emissions. However, before any further remedial actions can be contemplated, though, it is important to fully understand the actual causes of such large HCEs and help researchers both gain deep insights into the development of the research domain and identify valuable research topics for future study. This paper reviews existing literature focusing on the domain of HCEs. This critical review provides a systematic understanding of current work in the field, describing the factors influencing HCEs under the themes of household income, household size, age, education level, location, gender and rebound effects. The main quantification methodologies of input–output models, life cycle assessment and emission coefficient methods are also presented, and the proposed measures to mitigate HCEs at the policy, technology and consumer levels. Finally, the limitations of work done to date and further research directions are identified for the benefit of future studies. [ABSTRACT FROM AUTHOR]

Despite strong correlation between Lean and Green, companies have found it challenging to integrate and implement Lean and Green practices simultaneously especially when resources are limited. Although there are existing model, framework, and methodologies, some limitations and challenges still exist. This paper aims to overcome some of the limitations and challenges from the existing works. Specifically, one of the objectives is to propose a methodology that aims to integrate Lean and Green practices, and enables the implementation of the integrated Lean and Green practices in an easy and practical manner. To achieve this objective, the proposed methodology will adopt and streamline some of the approaches used in existing works. In this methodology, an easy-to-track metric called Carbon-Value Efficiency, which aims to integrate metrics derived from Lean and Green implementation, is introduced. The other key objective is to demonstrate the applicability of the proposed methodology using a case study of metal stamped parts production. The results show that Carbon-Value Efficiency can be improved by 36.3%, given an improvement in production lead time by 64.7% and a reduction in carbon footprint by 29.9%. This case study demonstrates that the proposed methodology helps to overcome the challenge in integrating and implementing Lean and Green practices, and achieve beneficial results. Future work could study other cases and explore other case specific supporting tools and techniques in order to enhance the proposed methodology. [ABSTRACT FROM AUTHOR]

The non-metallic minerals industry is the third-largest industrial energy consumer, and it constitutes around 7% of global CO 2 emissions due to the high energy intensity of production processes. Although the substantial improvement of the energy efficiency of this industry in the EU observed since 1995, the energy intensity of this sector is still relatively high. To reach the goals of the Paris Agreement, it is necessary to implement further steps towards the decarbonization of this sector. Previous works do not provide information about research trends in this field or the current development of technologies. To fill this gap, the following research questions have been asked: (Q1) which decarbonization measures are already applied or under development in the non-metallic minerals sector?; (Q2) which of these measures might bring breakthrough to this sector?; (Q3) what is the impact of these measures on costs, energy consumption and GHG emissions? To this end, this paper performs a systematic literature review of GHG emission mitigation options of the non-metallic minerals industry by screening 2964 articles and performing an in-depth analysis of 48 full-text relevant articles following the PRISMA approach. The results show that the carbon capture, utilization and storage (CCUS) is the most popular research topic and has the highest decarbonization potential for the industry (up to 60%). However, more research is needed for the full-scale implementation. Further lowering the clinker to cement ratio to at least 75% is also of major importance, however, it is a mature technology, and not much research is required in this field. Despite the relatively low representation in scientific literature, heat electrification is an unavoidable direction for the industry in the long term, resulting from the global shift towards sustainable energy from renewables. The article also sets directions for future research, especially in terms of further development of the most promising technologies and on the industry transition pathways that would be legally adopted at the international level. • The non-metallic minerals industry constitutes around 7% of global CO 2 emissions. • A systematic literature review of GHG emission mitigation options of the industry. • 2964 articles screened and 48 full-text articles analyzed. • CCS is the most discussed mitigation option, yet not ready for commercialization. • Heat electrification is an unavoidable direction, resulting from the climate policy. [ABSTRACT FROM AUTHOR]

Abstract: Green public procurement is often promoted as a tool to reduce energy use and CO2 emissions in the supply chains of public entities. However, only a limited number of studies has quantitatively assessed the environmental impacts of green public procurement schemes. The aim of this paper was to assess the potential impact of the CO2 Performance Ladder on the reduction of carbon dioxide emissions in the Netherlands. The CO2 Performance Ladder is a new green procurement scheme that is currently used by several Dutch public authorities. It is a staged certification scheme for energy and CO2 management. Achieving certification gives companies a competitive advantage in the contract awarding process. Currently, more than 190 companies participate in the scheme. The scheme accounts for 1.7 Mt of aggregate CO2 emissions, corresponding to nearly 1% of national greenhouse gas emissions in the Netherlands. Since the introduction of the scheme, total CO2 emissions have decreased substantially. Nevertheless, these emission reductions should be interpreted with caution because the emission reductions are largely due to reductions by a few companies, and the level of emissions is affected to a large extent by economic activity. The companies participating in the scheme have set different types of CO2 reduction targets with varying levels of ambition. The projected impact of reaching these targets on CO2 emissions is a total CO2 emission reduction in the range of a 0.8–1.5%/yr, with a most likely value of 1.3%/yr. The CO2 Performance Ladder could therefore contribute significantly to achieve the annual reduction rate necessary to remain below the 2020 Dutch emission ceiling for sectors not included in the European Union Emission Trading Scheme. [Copyright &y& Elsevier]

Abstract: Geopolymer concrete is seen as a potential alternative to standard concrete, and an opportunity to convert a variety of waste streams into useful by-products. One key driver in geopolymer development is the desire to reduce greenhouse gas emissions from the production of concrete products. This paper presents an examination of the lifecycle cost and carbon impacts of Ordinary Portland Cement (OPC) and geopolymers in an Australian context, with an identification of some key challenges for geopolymer development. The results of the examination show that there is wide variation in the calculated financial and environmental “cost” of geopolymers, which can be beneficial or detrimental depending on the source location, the energy source and the mode of transport. Some case study geopolymer concrete mixes based on typical Australian feedstocks indicate potential for a 44–64% reduction in greenhouse gas emissions while the financial costs are 7% lower to 39% higher compared with OPC. [Copyright &y& Elsevier]

The International Maritime Organisation has set a goal to achieve a 50% reduction of the total annual greenhouse gas emissions related to the international shipping by 2050 compared to the 2008 baseline emissions. Thus, companies are looking for solutions and measures to align with the Organisation's goal. Marginal Abatement Cost Curves have been extensively used in the literature to rank several Greenhouse Gas mitigation measures based on their costs of reducing an additional unit of pollution. In this paper an expert-based, bottom-up approach was employed to construct Marginal Abatement Cost Curves for a globally operating ship-management company. Several mitigation measures were examined for the following vessel categories (a) Containerships 8000+ TEU, (b) Containerships 2000–2999 TEU, (c) Bulkers 35000–59999 DWT, and (d) Gas Tankers <49999 CBM. Furthermore, the fuel price fluctuation and carbon taxation were used to investigate the sensitivity of baseline Marginal Abatement Cost Curves. The measures, which remain cost-effective under all sensitivity analyses, undergo a Pareto Analysis and a Marginal Cost-Effectiveness Analysis. The results suggest that most of the recommended mitigation measures are of an operational and technical nature, with exception the burning of Liquified Natural Gas and the installation of Flettner Rotors for the Gas Tankers. The company could save up to 17% CO 2 emissions and approximately 2 million dollars per year compared to the 2019 baseline by employing all recommended mitigation measures to all vessel categories. In addition, Carbon Storage and Capture could become a cost-effective solution with appropriate carbon taxation, but it is not the ultimate solution since it does not lead to independence from fossil fuels. The study also reveals that depending on the operating condition, even within the same vessel category, different mitigation measures should be employed. • Expert-based, bottom-up and company-specific MACCs for the shipping sector. • GHG mitigation measures' cost-effectiveness for Containerships, Bulkers and Tankers. • Comprehensive way of ranking measures with negative marginal abatement costs. [ABSTRACT FROM AUTHOR]