The heterogeneity in energy consumption between households has long been neglected, leading to the low effectiveness of one-size-fits-all demand-side policies. Here, we investigate energy consumption ...patterns and home appliance purchasing preferences of different urban households. In this study, 1921 urban households in China were empirically classified into four groups based on their socio-demographic characteristics. It is found that low- and middle-income small-size households have a latecomer energy consumption pattern and a rational home appliance purchasing preference, low-income large-size households correspond to an old-fashion pattern and an economic preference, middle- and high-income large-size households show a moderate pattern and a neutral preference, and high-income small-size households perform a modern pattern and a pro-environmental preference. The inter-group comparison indicates that income increase will promote energy consumption patterns to be more low-carbon and modern. Meanwhile, the demographic transition to small-size family may lead to a carbon-intensive energy lifestyle for middle-income households, while high-income households can have a more saving and green energy consumption pattern. In addition, the scenario analysis indicates that one-size-fits-all policies failed to account for everyone. The findings presented here can inform authorities of the necessity and directions of designing common but differentiated household energy-saving policies.
•1921 urban households are empirically classified into four household groups.•Four energy consumption patterns are identified corresponding to groups 1–4.•There are differences in home appliance purchasing preferences among groups 1–4.•Different households show different levels of response to the same policies.•Common but differentiated household mitigation policies should be designed.
Per capita energy consumption is related to the equity of energy resource allocation, and its wide regional variations probably aggravate the unbalanced regional development. However, whether the ...gaps in China's provincial per capita energy consumption are reduced over the past decades has not yet been thoroughly investigated, and the convergence of provincial per capita energy consumption is crucial for relevant energy policy making. This study serves to investigate the convergence pattern of per capita aggregate energy consumption across 30 Chinese provinces throughout 1990–2017, with the application of a club convergence approach. Then several energy conservation scenarios, as well as their convergence are discussed. The results indicate that the full sample of 30 provinces cannot converge to a common level in per capita energy consumption, and 7 provinces of which converge to a level, while the rest converge to another level. However, the convergence of full sample in per capita energy could be achieved over 1990–2017 in a scenario of energy consumption reduction for some specific provinces with higher energy consumption per capita. We suggest that Xinjiang, Inner Mongolia, Qinghai and Shanxi should take more efforts to reduce energy consumption in process of achieving convergence of the full sample.
•Convergence of provincial energy consumption per capita in China is investigated.•The null hypothesis of convergence of full sample is rejected by the logt test.•Two convergence clubs with different convergence levels are identified.•Energy conservation scenarios are discussed to achieve convergence of full sample.
•End-use of electricity consumption in residential buildings in Gulf Cooperation Council countries was presented.•Discrepancies in certain indicators have been observed by the end-use of electricity ...consumption.•Improving the efficiency of air conditioners and thermal insulation of the walls are the best measures to conserve electricity in residential buildings.•The results can be used in areas with a similar climate, living standard, buildings types, and the inhabitants' behavior.
Energy conservation and improvement in energy efficiency yield multiple technical, economic, environmental, and social benefits and realize comfort and sustainability of residential buildings (RBs). This review paper presents the end-use of electricity consumption in RBs and the results of economic analysis. In addition, a description and discussion of studies on energy conservation measures, Net Zero Energy Building, and renewable energy in RBs are discussed. The percentage of end-used energy consumption for different purposes obtained in many studies are often not consistent. Moreover, discrepancies in certain indicators have been observed, necessitating the need to clarify the factors in the consumption of electricity in RBs. Further, a few studies used the term energy consumption in buildings (total or electrical); however, specifying the type of buildings to identify and use the necessary indicators of energy consumption in each type of building are desirable. Furthermore, most studies emphasized improving the efficiency of air conditioners and thermal insulation of the walls as these are the best measures to conserve electricity.
Zero liquid discharge (ZLD)a wastewater management strategy that eliminates liquid waste and maximizes water usage efficiency has attracted renewed interest worldwide in recent years. Although ...implementation of ZLD reduces water pollution and augments water supply, the technology is constrained by high cost and intensive energy consumption. In this critical review, we discuss the drivers, incentives, technologies, and environmental impacts of ZLD. Within this framework, the global applications of ZLD in the United States and emerging economies such as China and India are examined. We highlight the evolution of ZLD from thermal- to membrane-based processes, and analyze the advantages and limitations of existing and emerging ZLD technologies. The potential environmental impacts of ZLD, notably greenhouse gas emission and generation of solid waste, are discussed and the prospects of ZLD technologies and research needs are highlighted.
Blending two or more amines has recently been recognized as an efficient strategy to formulate competitive sorbents for post-combustion CO2 capture, as it allows to benefit from the advantages of ...each individual amine. In the present work, we devised four new dual-amine aqueous blends, based on the tertiary amine 2-dimethylamino-2-methyl-1-propanol (2DMA2M1P) mixed with different primary and secondary amines, namely ethanolamine (MEA), benzylamine (BZA), 2-amino-2-methyl-1-propanol (AMP) and diethanolamine (DEA). The CO2 capture and release performance of the formulated blends were experimentally evaluated by measuring CO2 equilibrium solubility, CO2 absorption and desorption rates, and energy consumption during the regeneration process, and results were compared with those obtained under the same operating conditions with 5 M aqueous MEA, the reference sorbent for CO2 capture processes. Moreover, 13C NMR spectroscopy was used to identify and quantify the species formed during the CO2 absorption process to better understand the reaction mechanism in each blend. We found that all formulated blends showed appreciable CO2 capture performance and, most importantly, significantly better desorption performance than conventional MEA. In particular, BZA+2DMA2M1P provided the best capture performance, while AMP+2DMA2M1P showed a faster CO2 desorption rate and lower energy consumption than the other tested blends.
•The CO2 capture performance of four proposed new dual-amine blends were investigated in detail.•The CO2 capture mechanism has been thoroughly investigated and explained through a13C NMR speciation study.•The heat consumption of the proposed dual-amine blends is less than that of MEA.
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•Critical review of energy consumption of seawater reverse osmosis plants.•Collection of more than 70 datasets for large-size seawater reverse osmosis plants.•Investigation of trends ...in the application of seawater reverse osmosis plants.•Analysis of factors associated with energy consumption of seawater reverse osmosis.•Future directions to reduce energy consumption of seawater reverse osmosis plants.
High specific energy consumption (SEC) is the main barrier for the expansion of seawater reverse osmosis (SWRO). Therefore, the main objective of current SWRO research is to lower the SEC of SWRO plants. However, SEC of SWRO plants has not been systemically explored or analyzed, despite the need for information to develop appropriate strategies to reduce SEC. Therefore, this study aims to review and analyze SWRO plants for a comprehensive understanding of their SEC. First, trends in SWRO application are investigated using more than 70 datasets on large-scale SWRO. The analysis explains the increasing number of large-size SWRO plants, the SEC reduction by isobaric energy recovery devices (ERDs), and the use of different SWRO configurations to meet the energy and quality requirements. Factors associated with SEC (i.e., feed conditions, target conditions, and equipment efficiency) are also analyzed. High salinity increases energy demand, whereas the temperature effect on energy consumption is not entirely clear. High-efficiency ERDs and pumps can reduce SEC, but overall SEC cannot be explained by these factors alone. SEC is also affected by target water quality and quantity. Moreover, specific SWRO designs can improve the system to efficiently achieve the established goals. Furthermore, future directions to develop low-energy SWRO plants are discussed.
Blending of produced hydrogen from renewable energy resources into the natural gas (NG) grid has been promoted as a viable means of energy transportation and long-time storage in large-scales. ...However, variation of thermo-physical properties of hydrogen-NG admixture can impact the performance of the measuring devices, accessories, and end-use appliances. Therefore, present work investigates the effect of the hydrogen addition on the thermo-physical properties of NG from gas fields with different compositions. The permissible hydrogen concentration, which obviates the need for alteration or modification of the equipment, is considered to be between 1 and 10 vol%. The investigations are conducted on the most important characteristics of the mixture, and it is observed that hydrogen injection into NG increases the upper and lower flammability limits and compressibility factor, while both lower and higher heating values, lower and higher Wobbe indices, along with the relative density decrease with hydrogen concentration increase. Results show that although injecting up to 10 vol% hydrogen into NG causes a reduction of about 7% in lower heating value for investigated compositions, the NG consumption with the NG + H2 admixture is reduced about 3.5%. Energy consumption of the compressors increases by around 9–14%, depending on the composition of the NG.
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•The investigations are done to calculate thermophysical properties of H2+NG mixture.•The hydrogen admixing to the natural gas is investigated in the range of 1–10 vol%.•Compressibility factor of the H2+NG mixture is calculated by using AGA8 EOS.•The investigations are also done for energy consumption of turbo-compressors.
The application of statistical and artificial intelligence (AI) tools in building energy prediction (BEP) is considered one of the most effective advances towards improving energy efficiency. Thus, ...researchers are constantly propagating the energy prediction field with many prediction models using diverse statistical and AI tools. However, many of these tools are employed in unsuitable data conditions or for wrong situations. Using the Institute of Electrical and Electronics Engineers (IEEE) and Scopus databases, 92 journal articles on statistical and AI tools in BEP were systematically analysed. Furthermore, a quantitative bibliometric analysis was conducted to pinpoint the trends and examine knowledge gaps. This research reviews the performance of nine popular and promising statistical and AI tools with a primary focus on 7 pertinent criteria within the building energy research domain. Although it was concluded that no one tool is best in all criteria, a diagrammatic framework is provided to serve as a guide for appropriate tool selection in various situations. This study contributes to appropriate tool selection in the development of BEP models and their related drawbacks. Additionally, this study also evaluated the performance of the high-performing tools on a standard dataset.
There has been concern that economic globalization will increase energy consumption and reduce energy efficiency. A slew of studies investigating this assertion have used trade, foreign investment, ...or both as indicators of economic globalization, with mixed findings. A number of concerns challenge the empirical literature including measurement issues, infrequent temporal variations in the data, business cycle effects and heterogeneity bias, which affect the causal ability of economic globalization. This study used global data of 141 countries to assess the effects of economic globalization on energy efficiency. Our identification strategies involved using more refined measures of economic globalization and energy efficiency, addressing infrequent temporal variations as well as business cycle effects and concerns of heterogeneity bias. Largely, economic globalization positively drives energy efficiency, but this effect suffers from upward bias without controls. We note that infrequent temporal variations in the data and business cycle effects and heterogeneity bias drive the result. Concerning the latter, the result has shown that economic globalization improves energy efficiency only in upper-middle and lower-middle income countries and not in high and lower-income countries. Our results raise serious caution about the causal abilities of existing studies. And we discuss the policy implications.
•We examine the role of economic globalization in energy efficiency for 141 countries.•Identification strategies involve using refined measures of globalization and efficiency and•Addressing infrequent temporal variations in data and heterogeneity bias.•Economic globalization enhances energy efficiency, but there is upward bias with controls.•Temporal variation in data and heterogeneity bias drive the result.
Improving access to affordable modern energy is critical to improving living standards in the developing world. Rural households in India, in particular, are almost entirely reliant on traditional ...biomass for their basic cooking energy needs. This has adverse effects on their health and productivity, and also causes environmental degradation. This study presents a new generic modelling approach, with a focus on cooking fuel choices, and explores response strategies for energy poverty eradication in India. The modelling approach analyzes the determinants of fuel consumption choices for heterogeneous household groups, incorporating the effect of income distributions and traditionally more intangible factors such as preferences and private discount rates. The methodology is used to develop alternate future scenarios that explore how different policy mechanisms such as fuel subsidies and micro-financing can enhance the diffusion of modern, more efficient, energy sources in India.