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Abstract Circular Economy has emerged as a popular research topic that is shaping public policy in Europe, China, America and elsewhere. It complements the conceptual basis of the Industrial Ecology framework, but places more emphasis on business models to create closed-loop material systems. However, the Circular Economy concept currently lacks robust engineering design methods, leading to many researchers question its effectiveness. In contrast, Process Integration is lesser known publicly, despite being widely applied in industry to achieve substantial reductions in industrial energy, water, and utility use. These three areas have developed in parallel with minimal cross-pollination, but are in fact potentially complementary. This contribution proposes the new unified concept of Circular Integration for greater transdisciplinary research cohesiveness in the sustainable development of processes, industries, and economies. Circular Integration combines elements from Process Integration, Industrial Ecology, and Circular Economy into a multi-dimensional, multi-scale approach to the minimisation of resource and energy consumption. Circular Integration thus provides an engineering toolbox for planning a Sustainable and Circular Economy. To demonstrate its potential, the paper presents a case study on sustainable biofuel production. The possible solution leverages existing industrial resources to potentially produce enough fuel to fulfil 37% of current demand for global air and marine transport. The Circular Integration framework can also be generalised to systems other than transport and energy, aiming to catalyse greater transdisciplinary research for the analysis, design, and implementation of sustainable and circular systems. Highlights • A new Circular Integration framework is developed to support a Circular Economy. • The framework uses insights from Industrial Ecology and Process Integration. • Its implementation creates new prospects for transdisciplinary research. • Global air and marine transport is analysed to demonstrate the new framework. [ABSTRACT FROM AUTHOR]

Passive design strategies are important for achieving building sustainability given their proved influences over the building performance in both energy and indoor environmental aspects. The building layout, envelope thermophysics, building geometry and infiltration & air-tightness are major passive architectural parameters to improve the building energy efficiency. In this paper, a comprehensive literature review on simulation-based approaches to optimize passively designed buildings is conducted and corresponding research gaps are identified. Based on existing research methods, modelling experiments on a generic building are conducted to integrate robust variance-based sensitivity analyses with an early-stage design optimization process. Proposed mixed-mode ventilation and lighting dimming control algorithms are applied to the EnergyPlus model to simulate the total lighting and cooling energy demands by incorporating the related design criteria in a local green building assessment scheme. The non-dominated sorting genetic algorithm (NSGA-II) is then coupled with the modelling experiment to obtain the Pareto frontier as well as the final optimum solution. Different settings of NSGA-II are also investigated to improve the computational efficiency without jeopardizing the optimization productivity. Furthermore, the sensitivity of optimum design solutions to external environmental parameters in hot and humid areas are explored. Findings from this study will guide decision-makers through a holistic optimization process to fulfill energy-saving targets in a passively designed green building. [ABSTRACT FROM AUTHOR]

This paper is to explore the differences of the integrated value of shale gas development between the US and China. On the basis of an extensive literature survey and 17 in-depth personal interviewswith domestic experts, a fuzzy-AHP model is exploited herein to evaluate the development of shale gas in the US and China. The fuzzy-AHP model encompasses 21 indicators, which can be further categorized into 4 critical factors: (1) market prospects, (2) environmental impacts, (3) conditions of resource & occurrence, and (4) general conditions of extraction & utilization. Among the 21 indicators, market demand, cost and price, technologies, gas content, water contamination/supply, and policy contribute significantly to the integrated value of the model. According to the integrated value of the shale gas development in the US and China, the comparative analysis suggests that there is a large gap between these two countries. Furthermore, differences in shale gas development between the US and China are identified and reasons for these differences are analyzed. The US-China comparative analysis and the experience from US suggest that government policies will be crucial to determine the future development of shale gas in China and other countries. [ABSTRACT FROM AUTHOR]

Buildings consume large amounts of energy and resources and have a significant impact on environment. In 2010 buildings accounted for 32% of total global final energy use and 19% of energy-related GHG emissions. This energy use and related emissions may double or potentially even triple by mid-century. China is the world's largest energy consumer and CO 2 emitter. With the process of urbanization, China has been entering into a period of great prosperity for construction, about 1.6–2.0 billion m 2 buildings are constructed each year, which accounts for about 40% of the world's total new buildings. It is predicted that China’s building energy use and related emissions will continue to increase over the next 15 years. Therefore, promoting green building development has become an urgent issue in China. However, green building is a highly complicated system engineering, its promotion needs evaluation standards as technical support. Many countries had issued a series of green building evaluation standards since 1990. Currently, there are some representative green building assessment schemes. Code for Sustainable Homes (CSH) has been fully implemented as the national authoritative standard of the UK since 2010. Leadership in Energy and Environmental Design (LEED) developed by the USA, was revised and updated regularly with the latest version issued in 2013. China enacted its national evaluation standard for green building in 2006, and revised the standard in 2014. Based on introducing the latest evaluation standards for green buildings in China, Britain and United States, the paper compared these standards from 5 aspects including energy-saving, water-saving, material-saving, site selection and the outdoor and indoor environmental quality. The comparison mainly focuses on evaluation methods and evaluation indicators in the three standard systems. Besides, the characteristics of each standard system were summarized and some suggestions for improving China’s evaluation standard for green building were proposed. [ABSTRACT FROM AUTHOR]

To date, China has the world's largest wind power generation capacity, followed by the United States. Yet, China's utilization of this installed capacity trails that of the United States by a huge gap. This paper seeks to explain this gap by focusing on the role of institutions. First, it analyzes the institutions that either facilitate or impede wind integration in the two countries. Next, it synthesizes these institutions into coherent institutional logics for China and the United States. Then, it corroborates the institutional analysis with empirical evidence from China and the United States. Finally, it compares the two countries and summarizes what China can learn from the United States to reduce wind curtailment. Overall, this paper finds that China's dominant institutional logic of wind integration is state centrism and it is complemented by partial decentralization and liberalization – a system that is more conducive to capacity addition than capacity utilization. By contrast, the United States' dominant institutional logic of wind integration is market competition but a competing logic also exists which is regulatory interventionism – a system that aligns capacity addition and utilization better but engenders greater policy uncertainty. Because the two countries have distinct institutional logics that generate different root causes for wind curtailment, this paper argues that simply transplanting solutions from the United States to China will not work. What China can learn from the United States is to make incremental improvements to address the frictions between its dominant and complementary institutional logics. • China's dominant institutional logic of wind integration is state centrism. • The U.S.'s dominant institutional logic of wind integration is market competition. • Different institutional logics underpin different solutions to wind curtailment. • China shall make incremental improvements along its dominant institutional logic. [ABSTRACT FROM AUTHOR]