• Energy Research

Papermaking is a capital-intensive industry that requires a high consumption of plant fibers, energy, and water. Previous sustainability assessments of papermaking industry primarily focused on separate evaluations for multiple criteria without the integration for criteria and could not compare the overall priority of the production alternatives. The life cycle sustainability for the most representative boxboard production is analyzed as a case study in this work. Life cycle water consumption, energy consumption, greenhouse gas emissions, and internal costs are selected as the assessment criteria. The two multi-criteria decision-making methods are applied to integrate the above criteria to obtain the sustainability sequence under different production pathways. When the papermaking enterprises are regarded as decision-makers, the alternative using waste paper as raw material to manufacture boxboard is the most sustainable, following by mixed fiber. The sustainability sequence of the alternatives using wood and straw as raw materials is controversial due to the different calculation models. Changing the proportion of raw materials and the criteria weights might adjust sustainability sequence of the alternatives.

Abstract As an important energy-efficient production technology, polygeneration has attracted more and more attentions for its advantages of high energy efficiency, low production cost, and fewer emissions compared with the traditional industrial systems. The objective of this study is to develop a multi-attribute comprehensive assessment method for sustainability assessment of polygenerations under uncertainty conditions. Fuzzy best-worst network method which can incorporate the interdependences and interactions among the evaluation criteria has been developed for determining the weights of the criteria. Interval TOPSIS which can rank the alternative under uncertainties has been employed to rank the alternative polygeneration systems according to their sustainability performance. In order to illustrate the proposed method, an illustrative case including four industrial systems has been studied, and the results were also validated by interval grey relational analysis (GRA) method. Sensitivity analysis was also carried out to investigate the effects of the weights of the criteria on the sustainability ranking of the four polygeneration systems.

Climate change determines the retreat of ice. This has created a huge access to petroleum, attracting strong interest by some states, especially energy hungry-countries and increasing competition between states, resulting in tension and threats, even military ones. Climate change has, therefore, to be perceived as a threat to international peace and security. However, recognition of the nexus between climate change, human security and conflicts in the prism of international law and politics is weak, leading to a difficulty institutions have for regulating and governing this nexus. Climate change can thus be considered as threat-multiplier, something that can exacerbate existing tensions, and the resolution of this threat will be the most difficult task to achieve where adaptation takes place in fragile and vulnerable areas, such as the Arctic, an area which is highly exposed to environmental risks and uncertainty. The region is populated by one of the most vulnerable groups, the indigenous people, such as the Inuit of the Arctic with low adaptive capacity compared to the pace of change. In the Arctic Environmental Ocean governance, access to natural resources, the potential of navigability, extension of maritime borders, and the desire of some states to extend their jurisdiction, all depict a situation of criss-crossing potential conflicts that could escalate and should, therefore, be perceived as “tinderboxes”. This article relatedly explores the existing legal framework in the case of the Arctic environmental ocean to provide effective and legitimate governance for a peaceful and “stable space” to prevent threats from both Arctic and non-Arctic states. It will be shown that Arctic Environmental Ocean activities need multi-level governance (global, regional, national and local) and that Arctic environmental security challenges cannot be addressed without a broader holistic vision. The article treat the United Nations regulatory level and how it could support many issues which have an impact on Arctic Environmental Ocean governance, and the Law on the Sea. Methodologically, the way to increase effectiveness to maintain and stabilize the Arctic environmental ocean governance entails that “stability” is achieved by integrating elements of climatology, international law, political science and agent based modelling to act in a preventative way to protect the Arctic environmental ocean and its societies and formulate effective policies. The conclusion led on how the current Arctic environmental ocean framework could be changed in order to increase effectiveness by incorporating risk analysis into a universal equation based model to redesign a new regulatory package at United Nations level and recommend changes at institutional level.

Abstract The use of alternative energy sources instead of HFO has been recognized as a promising way for reducing emissions from shipping and promoting the development of green shipping. However, it is usually difficult for the decision-making to select the best choice among multiple alternative marine fuels. In order to address this, a complete criteria system for sustainability assessment of alternative marine fuels was firstly established, and a fuzzy group multi-criteria decision making method has been developed to rank the alternative marine fuels by combining fuzzy logarithmic least squares and fuzzy TOPSIS (Technique for Order Performance by Similarity to Ideal Solution). Fuzzy logarithmic least squares method has been employed to determine the weights of the criteria for sustainability assessment, and fuzzy TOPSIS was employed to determine the sustainability order of the alternatives. An illustrative case with three alternative marine fuels including methanol, LNG and hydrogen has been studied by the proposed method, and hydrogen has been recognized as the most sustainable scenario, follows by LNG, and methanol in the descending order. The results show that the proposed method is feasible for prioritizing the alternative marine fuels; it also has the ability to help the decision-makers to select the most sustainable option among multiple marine fuels.

Abstract The purpose of this study is to understand the effects of the influential factors that affect the sustainable development of new energy vehicle in China, investigate the cause-effect relationships among them, and propose some appropriate policies and efficacious measures for the policy-makers to promote its sustainable development. Interpretative Structuring Modeling was used to identify the critical factors affecting the sustainability of China’s new energy vehicle industry and to find the potential relationships among the factors; subsequently, fuzzy Decision Making Trial and Evaluation Laboratory was employed to investigate the cause-effect relationships among the influential factors and to prioritize these factors. The results reveal that technological maturity, technological standards for new energy vehicles, and funds on R&D of new energy vehicles are the three most important driving factors for promoting the sustainable development of new energy vehicle industry of China. Some implications were also proposed for China’s authority. The success factors and strategic implications of new energy vehicles in China were investigated in a multi-criteria analysis approach.

Abstract The selection of alternative energy sources for shipping can effectively mitigate the problems of high energy consumption and severe environmental problems caused by shipping. However, it is usually difficult for decision makers to select the most sustainable alternative energy source for shipping among multiple alternatives due to the complexity of considering different aspects of performances and the lack of information. This study developed a novel multi-criteria decision-making method that combines Dempster-Shafer theory and a trapezoidal fuzzy analytic hierarchy process for alternative energy source selection under incomplete information conditions. According to the developed method, nuclear power has been recognized as the most sustainable alternative energy source for shipping, followed by liquefied natural gas (LNG) and wind power, and sensitivity analysis reveals that the weights of the criteria have significant on the sustainability sequence of the three alternative energy sources for shipping. The developed method can be popularized for selecting the most sustainable alternative energy source despite incomplete information.

Abstract Desalination technology has been recognized as a promising solution for mitigating the pressure caused by water shortage. In order to help the decision-makers to select the most sustainable desalination process/technology, a multi-criteria decision analysis method under hybrid information was proposed for sustainability ranking of alternative desalination processes. The interval AHP (Analytic Hierarchy Process) method was employed to determine the weights of the evaluation, and the TOPSIS (Technique for Order Preference by Similarity to an Ideal Solution) under hybrid information was employed to determine the sustainability ranking of the alternative desalination processes. Comparing with the previous studies about desalination process selection, the proposed method can achieve desalination selection based on the decision-making matrix composed by multiple types of data (i.e. crisp numbers, interval numbers and fuzzy numbers). Accordingly, the challenges of uncertainties and the quantification on the soft criteria can be successfully solved. The results based on the developed model can facilitate the decision-makers to select the most sustainability desalination technology with the considerations of economic, environmental. Technological and social pillars simultaneously. Four alternative desalination processes including multi-stage flash system (MSF), low temperature multi-effect distillation (LT-MED), reverse osmosis (RO), and vapor compression distillation (VCD) were studied by the proposed method in this study, and the closeness degree (CD) of LT-MED which represents its integrated sustainability performance is 0.6984, followed by the CDs of MSF (0.5602), VCD (0.5381) and RO (0.4116), respectively. Thus, the sustainability ranking from the best to the worst is LT-MED, MSF, VCD and RO. The results were validated by the sum weighted method, and sensitivity analysis was also carried out. The results reveal that the selection of LT-MED as the most sustainable is robust.

Abstract In this work, a systematic method for conceptual design and multi-objective optimization of an energy-efficient and sustainable reactive/extractive distillation (RED) process is proposed to separate a ternary wastewater mixture with multi-azeotrope tetrahydrofuran/ethanol/water. Conceptual design of the proposed scheme is carried out by the analysis of thermodynamic feasibility (e.g., residue curve maps and iso-volatility line). In the proposed process, the component of water in the ternary system is firstly removed by adding the reactant in a reactive distillation column and the remaining binary azeotropic mixture is then separated via ED. During the ED process, the best entrainer dimethyl sulfoxide could be determined via the comparison of iso- and uni-volatility. An improved multi-objective genetic algorithm is employed for optimizing the established process with some key decision variables (e.g., feed locations and distillate rate). The results illustrated that the economic and environmental benefits of the proposed RED process will be greatly improved.