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• Decoupling of GDP from all energy sources under multiple principles are examined. • World economy achieved weak energy decoupling in most years during 2000–2011. • World economy coupled with coal use and tended to couple with cleaner energy use. • None of studied economies achieved long-term GDP-embodied energy decoupling. • Decoupling delusions occurred when only considering direct and total energy use. Decoupling indicators are widely used to understand links between economic growth and energy use. However, traditional decoupling analyses mostly focus on domestic energy consumption (i.e., the production-based principle) and neglect off-site energy use across global supply chains to satisfy an economy's final consumption (i.e., the consumption-based principle). Moreover, analyses for total primary energy conceal an economy's preference for different energy sources. Therefore, this paper evaluates decoupling states of GDP from all types of primary energy use under consumption-based principle, for world economy and eight typical economies during 2000–2011. Regarding total primary energy, world economy witnessed weak decoupling in most years, and most economies studied (e.g., USA, Japan and China) achieved decoupling initially but performed negative decoupling finally. For EU, USA, Japan, Russia and India, production-based decoupling performances were generally better than consumption-based ones. Decoupling phenomena detected under production-based principle even became coupling or negative decoupling under consumption-based principle in some cases. As for each energy source, world economy decoupled from oil use, but still coupled with coal use, and gradually showed a trend to couple with natural gas and renewables use. Different energy sources showed distinct decoupling degrees from GDP, affected by individual embodied energy requirement structure. This paper uncovers potential energy decoupling delusions to deepen the understanding of relationships between energy use and economic growth. [ABSTRACT FROM AUTHOR]

• Use of GFRG building technology promotes the concept of industrial symbiosis. • Reduction in initial embodied energy due to GFRG building technology is determined. • Benefits of GFRG technology include savings on materials, time and manpower needs. • Significant reduction in self-weight of GFRG buildings and its related advantages. The present situation vis-á-vis increased energy use and environmental emissions has urged the building sector to contribute more towards sustainable construction. This is possible only through appropriate choice of building materials and technologies that minimize the environmental impacts. Nevertheless, the adoption of the same need to necessarily satisfy the user in terms of aesthetics, utility and cost. This paper presents the comparison of embodied energy of a two-storey residential building, made using, i) GFRG (glass fibre reinforced gypsum), and, ii) load-bearing brick masonry, building technologies. GFRG technology uses load-bearing walls and slabs that are manufactured using gypsum waste, and consumes reduced quantity of reinforced concrete in comparison with conventional construction. It has been found in this study that the embodied energy related to building materials of the GFRG building is 16% less, and that associated with transport of resources is twice, compared to the conventional brick masonry building. The major advantages of the GFRG building construction are found to be about – reduction in structural weight and construction cost, – savings in construction time and – savings in total man power requirement for construction. Further, the use of cement, steel rebar and sand is reduced by 25%, 36% and 44% respectively. [ABSTRACT FROM AUTHOR]