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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]

Appliance labels are a widely used policy instrument to increase the adoption of energy-efficient technologies. Most countries use categorical labels to facilitate comparison of appliances based on energy consumption. Studies have found that consumers respond positively to the labels, but the differentiated response to the categories on labels is not well understood in the literature. This study presents the results of a discrete choice experiment corroborated by an analysis of secondary market data to demonstrate that consumers differentiate between label categories; with a greater value being placed on appliances with higher levels of energy efficiency performance. We examine two appliances - air conditioners and refrigerators and observe that there are some differences in consumer response - likely due to the different usage patterns of the two appliances. Consumer responses were observed in hypothetical choice situations constructed ensuring statistical and design efficiency. In a mixed logit model specification with correlated random parameters, the magnitude and the distribution of consumer preference for the highest category of energy efficiency are estimated. The results are validated by estimating the incremental price of higher category of energy efficiency using market data for comparison. The sources of consumer heterogeneity for the highest category of energy efficiency are identified after controlling for other consumer variables. The findings presented in this paper are useful for improving the effectiveness of existing energy efficiency programs and designing new programs to accelerate adoption of energy efficient technologies. [ABSTRACT FROM AUTHOR]

This paper presents a quantitative assessment of Sustainable Energy Security (SES) of the energy demand sub-system for India by calculating a multidimensional SES index. The demand sub-system has been evaluated for four dimensions of SES, viz., Availability, Affordability, Efficiency and (Environmental) Acceptability using 23 selected metrics. A hierarchical structure has been used to construct indices using ‘scores’ (objective values of selected metrics), and ‘weights’ (subjective values, representing importance of each metric) which are then aggregated, to obtain a SES index. Various sectors of the energy demand sub-system are evaluated and dimensional and sectoral indices are calculated for the years 2002, 2007 and 2012. Assessment of the obtained energy indices is undertaken (separately for rural and urban residential sector) and results reveal that all (except one) sectoral indices have shown an increase during the period of assessment. The results show that from 2002 to 2012, the aggregate SES index has increased by approximately 10% which indicates a gradual improvement in the sustainability and security of the energy demand sub-system. However, the SES index is approximately 0.7 (against a desired target of 1.0), which implies that there is still a large scope for improvement in the performance of the India’s energy demand sub-system. A sensitivity analysis of various indices reveals that the SES index is relatively robust to variation in weights allotted to different dimensions and hence provides a reliable assessment of the energy demand sub-system. [ABSTRACT FROM AUTHOR]

Abstract: Since 2003 India has been actively promoting the cultivation of Jatropha on unproductive and degraded lands (wastelands) for the production of biodiesel suitable as transportation fuel. In this paper the life cycle energy balance, global warming potential, acidification potential, eutrophication potential and land use impact on ecosystem quality is evaluated for a small scale, low-input Jatropha biodiesel system established on wasteland in rural India. In addition to the life cycle assessment of the case at hand, the environmental performance of the same system expanded with a biogas installation digesting seed cake was quantified. The environmental impacts were compared to the life cycle impacts of a fossil fuel reference system delivering the same amount of products and functions as the Jatropha biodiesel system under research. The results show that the production and use of Jatropha biodiesel triggers an 82% decrease in non-renewable energy requirement (Net Energy Ratio, NER=1.85) and a 55% reduction in global warming potential (GWP) compared to the reference fossil-fuel based system. However, there is an increase in acidification (49%) and eutrophication (430%) from the Jatropha system relative to the reference case. Although adding biogas production to the system boosts the energy efficiency of the system (NER=3.40), the GWP reduction would not increase (51%) due to additional CH4 emissions. For the land use impact, Jatropha improved the structural ecosystem quality when planted on wasteland, but reduced the functional ecosystem quality. Fertilizer application (mainly N) is an important contributor to most negative impact categories. Optimizing fertilization, agronomic practices and genetics are the major system improvement options. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, energy metrics (energy pay back time, electricity production factor and life cycle conversion efficiency) of hybrid photovoltaic (PV) modules have been analyzed and presented for the composite climate of New Delhi, India. For this purpose, it is necessary to calculate (1) the energy consumption in making different components of the PV modules and (2) the annual energy (electrical and thermal) available from the hybrid-PV modules. A set of mathematical relations have been reformulated for computation of the energy metrics. The manufacturing energy, material production energy, energy use and distribution energy of the system have been taken into account, to determine the embodied energy for the hybrid-PV modules. The embodied energy and annual energy outputs have been used for evaluation of the energy metrics. For hybrid PV module, it has been observed that the EPBT gets significantly reduced by taking into account the increase in annual energy availability of the thermal energy in addition to the electrical energy. The values of EPF and LCCE of hybrid PV module become higher as expected. [Copyright &y& Elsevier]

Abstract: This paper presents the suitability of artificial neural network (ANN) to predict the performance of a direct expansion solar assisted heat pump (DXSAHP). The experiments were performed under the meteorological conditions of Calicut city (latitude of 11.15°N, longitude of 75.49°E) in India. The performance parameters such as power consumption, heating capacity, energy performance ratio and compressor discharge temperature of a DXSAHP obtained from the experimentation at different solar intensities and ambient temperatures are used as training data for the network. The back propagation learning algorithm with three different variants (such as, Lavenberg–Marguardt (LM), scaled conjugate gradient (SCG) and Pola-Ribiere conjugate gradient (CGP)) and logistic sigmoid transfer function were used in the network. The results showed that LM with 10 neurons in the hidden layer is the most suitable algorithm with maximum correlation coefficients (R2 ) of 0.999, minimum root mean square (RMS) value and low coefficient of variance (COV). The reported results conformed that the use of ANN for performance prediction of DXSAHP is acceptable. [Copyright &y& Elsevier]

Abstract: This paper uses Granger causality tests to examine the differences of causal relationships between coal consumption and GDP in major OECD and non-OECD countries, using data for the period of 1980–2005. What we discovered is that unidirectional causality running from GDP to coal consumption exists in Japan and China, and no causality relationship between coal consumption and GDP in India, South Korea and South Africa while the series are not cointegrated in USA. The major OECD or non-OECD countries especially China, India and South Africa should reduce their CO2 emissions in coal consumption to reach sustainable development. [Copyright &y& Elsevier]