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The power industry is the industry with the highest carbon emissions in China, and the rational allocation of carbon quotas for the power industry is the key to the rational allocation of carbon quotas in China, while the transfer of carbon emissions generated by inter-provincial power trading makes it difficult to calculate the carbon emission quotas for power. The article calculates the comprehensive power carbon quota for each province based on the principles of equity(PEQ) and the principles of efficiency(PEF). The results of the study prove the following points. (1) There are significant differences in the carbon emission factors calculated for electricity generation and consumption in each province. (2) The western provinces with abundant electricity resources deliver electricity to the eastern and southern provinces to ensure their economic development, so the western provinces with higher inflows of electricity carbon emissions bear the carbon emission pressure of the eastern and southern provinces. (3) The provincial electricity carbon quota calculated by the principle of comprehensiveness(PC) takes into account social equity and economic efficiency, and the calculation results are more reasonable. This study achieves balanced regional development by reasonably allocating provincial electricity carbon quotas. • There are significant differences between the calculated carbon emission factors for electricity generation and consumption in the provinces. • The western provinces with larger inflows of carbon emissions from electricity bear the pressure of carbon emissions from the eastern and southern provinces. • The provincial power carbon quota allocation scheme under the principle of comprehensive combines the advantages of the responsibility principle and the efficiency principle. [ABSTRACT FROM AUTHOR]

Coal power plants are crucial in both the power sector and central heating sector and also emit large amount of carbon dioxide. Existing research on coal power plants transformation mainly focused on their role in the power sector, with insufficient attention paid to their heat and power cogeneration capabilities. To address this gap, this paper proposes a long-term expansion joint optimization model for power sector and central heating sector incorporating the competitive technologies in both sectors, which is used to obtain the optimal low-carbon transition pathway of power sector and central heating sector, and analyse the pathway of coal power plants. China is selected for a case study for its largest scale of existing coal power plants in the world and urgent need of decarbonization. Compared to the scenario only considering electricity generation function from coal power plants to power sector, another scenario also considering the heating production to central heating sectors brings less than 5% increase in their remaining capacity, whilst results in significant changes in their regional distribution. Proportion of heat and power cogeneration of coal power plants in the heat generation structure is expected to increase first to 80% in 2030 and decrease to 58% in 2055. • A long-term optimization model for sectors of power and central heating is built. • Impacts of considering heating sector on coal power plants paths are quantified. • Proportion of coal power plants in total heat production increases to 80% in 2030. • Electric heat pumps are developed rapidly for negative carbon emission constraint. [ABSTRACT FROM AUTHOR]

In this study, an interval-credibility-chance constrained programming (ICCCP) method which is capable of handling uncertainties presented as interval and interval-fuzzy-random values existed in the energy-water nexus (EWN) system is developed. An ICCCP-EWN model is formulated for planning energy-water nexus system of Xiamen that is heavily relies on fossil fuels (e.g., coal is a main energy source). A set of probability and credibility levels related to energy-water availabilities, energy-water demands, and pollutant-emission mitigations are examined. Results discover that uncertainties have significant effects on the system planning strategies. System cost, heat generation, imported energy, and water supply would decrease with the raised probability level and increase with the raised credibility level. Coal-fired would be the main contributor to electricity generation; however, its proportion would reduce from [59.4, 59.9]% to [40.5, 41.8]%. Gas-fired would increase from [27.4, 27.6]% to [41.5, 43.9]% of the total electricity generation. Surface water would be the main water source, sharing more than 65% of the total amount. One of the major water users would be gas-fired electricity generation, increasing from [32.1, 32.6]% to [42.1, 44.6]% in future. These findings can provide useful information for the study city to adjust the existing energy and water planning strategies to achieve the goal of sustainable development. • An interval-credibility-chance constrained programming model is proposed. • Energy-water nexus system planning model is formulated for Xiamen, China. • Interval-fuzzy-random uncertainties can affect the planning policies. • The system transforms from coal-dominated to gas-dominated (over 40%). • Surface water would be main water source (over 65%) and gas would be main consumer. [ABSTRACT FROM AUTHOR]

Transition to low carbon energy system requires number of metals that are required in other sectors, have limited availability, produced mainly as byproducts in limited countries, and classified critical, which may shift energy system traditional geopolitics. China is main producer of several metals and one of their main consumers, which may have implications on their use in other sectors and in low carbon technologies in other countries. We aim at analyzing electricity generation technologies (EGT) in China, their metals requirements, and their global implications. Metals included are Ag, Te, In, Ge, Se, Ga, Cd, Nd, Dy, Pr, Tb, Pb, Cu, Ni, Al, Fe, Cr, and Zn. Dynamic material flow-stock model and seven energy scenarios are used, combined with material scenarios. Results indicates that most critical metals for energy system are Te, Cr, Ag, Ni, In, Ge, Tb, and Dy, however, technology advancements are expected to reduce risks associated with Ag, In, Dy, and Tb. Energy scenarios are difficult to realize without adequate supply of metals from primary sources, combined with increasing resources efficiency, recycling, and careful selection of technologies. Energy models used to produce these scenarios should include energy-material nexus. Biggest global implications expected for Ge, Te, Tb, and Dy. • Electricity technologies and their metals requirements in China are analyzed. • A dynamic material flow-stock model and seven energy scenarios are used in the analysis. • Te, Cr, Ag, Ni, In, Ge, Tb, and Dy are the most critical metals for Chinese energy system. • China high metals demands in energy sector may constrain their use in other countries and sectors. • Metals availability should be included in energy models due to their impacts on scenarios realization. [ABSTRACT FROM AUTHOR]

In today's China, the reverse distribution of electricity resources and electricity demand makes large-scale and long-distance transmission of electricity inevitable, resulting in the problem of electricity allocation optimization. To address this problem in the region covered by the China Southern Grid (CSG), the paper establishes an optimized model for electricity generation and interprovincial trading strategies in southern China. Based on data from 2015, this paper simultaneously optimizes electricity generation and interprovincial trading strategies in each of the five provinces. The result shows that interprovincial trading in the CSG-served area can yield significant energy, economic, environmental and interconnection benefits. It can reduce the power supply cost and environmental pressure in Guangdong province, help make Yunnan province a hydropower base in China and a thermal power base in southern China, facilitate the completion of the "West-to-East Power Transmission" project, and partly resolve the issues raised in each province's 13th Five-Year Plan as well as the problem of optimizing electricity allocation in the region covered by the CSG. • We propose an annual total optimized model for electricity generation and interprovincial trading in Southern China. • The model optimizes the electricity trading and transmission routes across regions. • The model considers the generation cost and penalty cost of emitting CO 2 , SO 2 and NO x. • Corresponding policies and proposals are put forward for power grid and five regions in South China. [ABSTRACT FROM AUTHOR]

Abstract Compared with wind and solar power, biomass power has grown relatively slowly in China. With abundant biomass resources, the development of biomass electric power in China has potential advantages. This paper analyzed the environmental impact of biomass power in the construction and operation stages in comparison with wind and solar power. The results showed that biomass power produced relatively less emissions in the system construction stage at around 1700 ton CO 2 -e/MW. In the operation stage, biomass power projects achieved an average of 131462 ton CO 2 -e per year, which is greater than wind and solar power of equal installed capacity. Biomass power plants could achieve net emission reductions in a shorter time (0.39 year) after operation. The life cycle GHG emissions of biomass power projects are between 42 and 85 g CO 2 -e/kWh. The evidence pointed out that biomass power is worth supporting in China, from the perspective of environmental performance. Local governments should promote the sustainable supply of biomass materials and the development of renewable energy industry should depend on local conditions. Highlights • The unit emissions of biomass power from construction is around 1700 ton CO2-e/MW. • Biomass power projects achieved net emission reductions less than half year. • The life cycle GHG emission of biomass power projects are between 42 and 85 g CO2-e/kWh. [ABSTRACT FROM AUTHOR]

Abstract The imbalance between the distribution of coal resources and electricity demand makes the transport of energy a significant challenge for China’s electricity system. Moreover, with China’s air pollution control policies, more clean energy resources will be used to generate electricity, which will change regional power generation structures and influence the energy transport among regions. In this paper, a multi-regional model is developed to optimize the long-term generation and transmission structure of China’s electricity system by minimizing the accumulative system cost and considering regional resource endowments and air pollution control polices in four key areas. Results indicate that 1) the share of power generation from clean energy will increase from 24% in 2015 to 62% in 2050, 2) the structure of power generation in each region will be influenced by local water resource availability, and the total CO 2 emission will be reduced by around 16% in 2030 owing to the air pollution control policies, and 3) by 2050, coal will be mainly transported from the North to the Central, the South, the East and the Northeast, while the electricity will be transmitted to the Central, the South and the East from the Northwest, the North, the Southwest and the Central. Highlights • A multi-regional optimization model of China’s electricity system is developed. • The share of clean energy generation will increase from 24% in 2015 to 62% in 2050. • Resource endowment and environmental policy will affect regional energy structure. • The energy transport between regions are mapped from 2020 to 2050. [ABSTRACT FROM AUTHOR]

Many wind farms in northern China have faced a worrying phenomenon “wind curtailment” during the heating seasons. The limited operating flexibility of combined heat and power (CHP) units is one of the major barriers to integrating wind energy. In this study, wind power integration is enhanced by using the free heat storage of the primary district heating network (DHN) and introducing extra heat pumps (HPs). A novel short-term dispatch model is proposed to minimize the total primary energy consumption (TPEC) of the district energy system (DES). After necessary linearization processes, the unit commitment problem can be solved efficiently and analytically by the interior point method. A test DES that contains a real large-scale DHN is utilized to verify the feasibility of the proposed dispatch model. In case studies, comparisons are made to evaluate the improvement of wind power integration and TPEC reduction under different operating scenarios. The results show that both heat storage utilization and electric HP introduction can reduce wind curtailment considerably, however, exhaust heat recycling has a better performance. In addition, using the existing heat storage of the primary DHN could reduce the TPEC of DES further even if electric HPs have already been used. [ABSTRACT FROM AUTHOR]

The generation forecast helps to develop the scheduling plan of power sources, build a power balance system and ensure the adequacy of power supply to the power system at the macro level. Therefore, a novel structurally adaptive discrete grey Bernoulli model, called DHGBM(1,1), is proposed in this paper for the prediction of power generation. Firstly, the Hausdorff fractional order cumulative generation operation makes it possible to achieve new information prioritisation. As for the structure of the model, we have extended the nonlinear grey Bernoulli model with the introduction of a nonlinear dynamic structure term, which allows the model to simulate variable generation data and improves the adaptability of the model. In a comparative test of the algorithms, the well-performing differential evolution algorithm was used for hyperparameter optimisation of the model to obtain better predictive performance. Monte Carlo simulations and probability density analysis verified the excellent robustness of the model. In addition, through the simulation tests, we obtained a reasonable range of parameters for the structural terms, thus limiting the complexity of the model, and the phenomenon of model overfitting was effectively prevented. Finally, five actual cases of China's hydro, China's thermal, China's nuclear, China's wind power generation and China's electricity exports are predicted. • A novel nonlinear dynamic structural term is proposed. • A novel structural adaptive discrete grey Bernoulli model is developed. • The robustness analysis of the novel model is established. • Comparative study shows that the novel model is superior to other six models. [ABSTRACT FROM AUTHOR]

Solar-aided coal-fired power generation system (SCPGS) is a promising medium-term solution to reduce CO 2 and PM2.5 emissions from numerous coal-fired power plants in China, yet lacking of unified theoretical guidance. In the present work, firstly, various specific integration schemes are reasonably generalized and unified by theoretical modelling. Secondly, the “superposition effect” has been revealed that the overall coal-savability of SCPGS is determined by not only the direct benefit due to local integration of solar energy but also the global effect of the integration on the system components in a superposition way. Meanwhile, the “promotion effect” has been revealed that the promotability of SCPGS on solar thermal exergy is primarily dependent on the higher-temperature Rankine cycle but sensitive to the energy level coupling between the solar thermal energy and the working fluid. Thirdly, the comprehensive evaluation factor ( f ), which serves as the common evaluation index between different SCPGSs considering both the coal-savability and efficiency-promotability, is proposed. Finally, with the help of the comprehensive evaluation factor, examples of application are given as demonstration for the comprehensive evaluations between 12 individual cases of SCPGS within a common framework. The present work is expected to fundamentally guide the future research and application of SCPGS. [ABSTRACT FROM AUTHOR]

Despite growing concerns over China's Belt & Road Initiative (BRI)'s electricity generation projects, studies analyzing the suitability of such projects to importing countries are rare. Filling this gap, this article assesses the opportunities and challenges of the BRI coal, hydro, wind, and solar power projects. To exploit the full benefits of both qualitative and quantitative approaches, this study uses Analytic Hierarchy Process (AHP), which enables quantitative analysis of the qualitative methods of the interviews and of the Strengths, Weaknesses, Opportunities, and Threats (SWOT) analysis elaborated via consultation of experts. While the BRI power cooperation is a real chance to offer cleaner and more efficient electricity generation especially in developing countries, more emphasis on sustainable development can better guide the BRI power projects. • Despite growing needs, researches concerning the BRI energy cooperation remain rare. • China is leading the global export market of coal, hydro, wind, and solar power. • This article assesses the BRI power projects and offers experts insights. • Large coal and hydro power plants are hampered by socio-environmental concerns. • Challenges can be attenuated via sustainable and competitive wind and solar energies. [ABSTRACT FROM AUTHOR]

Compressed air energy storage (CAES) is a method of energy storage which can convert the surplus power to the internal energy of compressed air, and regenerates electricity whenever power is needed. A clean CAES system coupled with wind and solar energy was developed to solve the dependence of traditional CAES system on fossil fuels in China. The operating variables of the hybrid system include heat exchanger effectiveness, ambient temperature, mass flow rate, total pressure ratio and compressor/turbine stages. The effect of these variables on the system performance was evaluated, including output power, overall efficiency, energy ratio ( ER ) and heat ratio ( HR ). The parameters, delineating criteria of the potential development localities for the hybrid CAES system sites, such as solar and wind energy resources, abandoned cavities of mines resources used as compressed air containers and the distribution of cross-transmission lines in China were investigated. By this research, it was found that more than 13 major zones were of the capability to support the hybrid system in China. Finally, the environmental and economic benefits of this CAES system were calculated, comparing to the conventional thermal power plants; restrictions and policy supports of the CAES systems in China were discussed as well. [ABSTRACT FROM AUTHOR]

As a major contributor to carbon dioxide emissions, the electric power sector has instigated significant changes in environmental issues. To show the effectiveness of the program, research on whether the changes of electricity production and CO 2 emissions are out of sync are conducted by applying a decoupling elasticity analysis method. Then the decoupling index from the electricity analysis on the basis of the extended multilevel LMDI method are applied to study Shandong Province, covering the period from 1995 to 2012. Finally, a comparative decoupling stability analysis is applied. Our results indicate electricity output and coal consumption play significant roles in determining levels of CO2 emissions. Also, “relative decoupling” and “no decoupling” were the main states during the study period. We also found that the decoupling index performed better (in terms of stability) than did the electricity output elasticity of CO 2 emission. [ABSTRACT FROM AUTHOR]

Renewable energy plays significant role in achieving energy savings and emissions reduction. As a sustainable and environmental friendly renewable energy source, concentrated solar power (CSP) is of interest for research and development. This is because CSP plants can be equipped with thermal storage systems, thereby producing electricity when sunlight is not available. The installation of CSP plants also leads to substantial ‘peak shaving effects’. However, the cost of CSP generation is an obstacle hampering the commercialization of this emerging industry. This paper constructs a mathematical model of the levelized cost of energy (LCOE) to calculate the power generation cost of CSP projects on the basis of lifetime cost structure analysis. A sensitivity analysis is conducted to examine the impact of different variables on the LCOE of CSP projects. The variables considered in this study are investment cost over the construction period, annual operation and maintenance cost, annual electricity production and the discount rate. Finally, the influence of incentive policies such as preferential loans, tax support and zero land cost for power stations is analyzed. This research offers a new method for power generation cost calculation of CSP projects and provides support for governments to formulate incentive policies for the industry. [ABSTRACT FROM AUTHOR]

The rapid increase in world's installed wind energy capacity may have masked the power loss caused by declining global surface wind speed (termed 'global stilling'), particularly for China with huge wind energy investments. Here, we estimated the potential impact of global stilling on wind energy production in China, using data from 1226 meteorological stations between 1971 and 2015. We show that surface wind speeds have on average declined at a rate of 5.5% decade−1, while the corresponding wind power density dropped by 24.5% decade−1. Although the decline in wind speeds has slowed after 1991, the decline in wind power density did not show this slowdown. This was attributed to the absence of slowdown in the declining trend of strong winds. Compared with the wind speed levels in the 2000s, the mean capacity factor would have dropped from 20.7% in 2001 to 14.9% in 2015, with the largest absolute change in the "Three North" regions. Furthermore, wind electricity generation would have declined by 40 TWh/a using the installed capacity of 2015, representing a decrease of 16%. The correlation analysis indicates that the decreased wind speed is most likely caused by changes in the large-scale atmospheric circulation rather than increased surface roughness. • We quantified the influence of global stilling on wind energy in China. • The large-scale circulation variability is probably the main cause of wind stilling over China. • We proposed some strategies for wind energy to cope with climate system change. [ABSTRACT FROM AUTHOR]

China has played an active and constructive role in the global combat against climate change. Municipalities play a leading role in tackling global climate change. However, despite the global efforts to push for carbon neutrality, the pathway is not yet clear. Using the municipality of Bengbu as a case, this paper explores pathways for achieving carbon emission peak and carbon neutrality in order to reach a CO 2 emission peak before 2030 in four Scenarios and develops a low emission framework taking into consideration the local economy, population, renewable resources, as well as the transport and energy sectors based on the Low Emissions Analysis Platform (LEAP) model. Meanwhile, the energy demand, the structure of the electric power generation, the CO 2 emission, and the total cost in different Scenarios are simulated respectively. The result of this study provides insight on options for energy transformation for the period of 2020–2060. The results show that the industrial sector is the largest energy consumer. The growth rate of energy demand in the primary industry and industrial sector shows downward trends. The increasement of industrial electrification rate and coal generation phasing out are crucial to CO 2 emission reduction. The large-scale deployment of renewable energy and the deployment of thermal power generation with CCUS are important for the electric power industry to achieve carbon reduction goals. Last but not the least, recommendations on energy planning for municipals to realize carbon emission peak and achieve carbon neutrality are provided. • Pathways for achieving carbon reduction targets of the municipality based on the LEAP model are explored. • The coal generation phasing out is prerequisite to CO 2 emission reduction. • The large-scale deployment of renewable energy is crucial for the electric power industry to achieve carbon reduction goals. • The deployment of thermal power with CCUS is necessary for the electric power industry to achieve carbon reduction goals. • Restructuring of industrial energy consumption and increasing the electrification rate are significant. [ABSTRACT FROM AUTHOR]

In 2003, China implemented market-oriented reforms to its electric power industry, aimed at improving the generation efficiency of its thermal power plants. In this paper, we use the polynomial functions, PLS (partial least squares) algorithm, and generation efficiency data from 1993 to 2012 to evaluate the effect of these reforms. Empirical analysis shows that the reforms caused a sudden down shift of 0.142 kW h per kg SCE (standard coal equivalent) to the “natural” generation efficiency curve of the thermal power industry, resulting in 555.8 million tons of SCE of wasted fossil energy during 2003–2012. This was mainly due to the non-implementation of electricity price bidding. To improve the generation efficiency of the thermal power plants, market competition should be further introduced into China's electric power industry as a matter of urgency. The major policy adjustment directions include: a) Electricity price bidding should be promoted by sub-region according to the unified trading rules designed by the central government; b) Over-the-counter transaction should be permitted; as well as c) Dynamic incentive mechanisms for renewable energy development should be established. [ABSTRACT FROM AUTHOR]

A major share of China's total carbon dioxide (CO 2 ) emissions is from the electric power sector. In 2010, almost 40% of all CO 2 emissions in China were from this sector. This is because the country predominantly depends on thermal electricity generation to meet its power requirement. This study analyses the CO 2 emissions from thermal electricity generation in China between 2000 and 2012 at the regional grid level. Logarithmic Mean Divisia Index methodology is employed to identify the factors that influence changes in CO 2 emissions over time. This study also predicts China's energy consumption and CO 2 emissions patterns between 2013 and 2020, forecasting rates of increase in energy consumption across six regional grids from 0.9% to 9.7%. CO 2 emissions related to thermal electricity generation increased from 981.33 million tons (Mt) in 2000 to 3342.79 Mt in 2012, which is an annual growth rate of 10.75%. These increases are not aligned with China's commitments on reducing emissions to the Asia-Pacific Economic Cooperation forum. China's CO 2 emissions are forecasted to increase to 5596 Mt by 2020 if the current increasing trends is not effectively curbed after 2012. [ABSTRACT FROM AUTHOR]

Most of the existing biomass power plant location models and supply chain designs are developed only for the minimization of logistics cost, having neglected the pollutant emissions during biomass feedstock transportation. How to achieve a win-win situation between the two for optimal power plant locations has become a main research direction. This paper, integrating the economic and environmental dimensions of sustainable development, develops a bi-objective 0–1 integer programming model for optimal locations and corresponding feedstock supply chain designs of biomass power plants. Having made improvements to the existing location models, this model is developed basing on the relevant research data of Chinese biomass power generation. A numerical example analysis is done in order to validate the model and to highlight the practicality and effectiveness. It is expected that this model may provide scientific guidance for biomass power plant siting and improve their environmental performance while still remaining economically competitive. [ABSTRACT FROM AUTHOR]

The recovery of waste heat is important for energy saving and carbon reduction in China. Although numerous technologies for waste heat recovery in China have been analyzed, research is still insufficient to provide an overview of the waste heat potential within the entire energy system. To fill this gap, this paper applies a top-down energy efficiency analysis to develop a Societal Waste Heat Accounting Model to quantify the waste heat potential in China. By indicating the total amount, sector and temperature distribution, and the ability to perform work of waste heat for China in 2018, the results revealed that: a) waste heat occupies 42% of total primary energy inputs, and 26% of primary energy and carbon emissions can be theoretically saved by utilizing waste heat. b) the electricity generation sector is the main source of waste heat, accounting for 45% of the total, of which 88% is below 100 °C. c) the industry sector has a wide range of temperatures, mostly above 300 °C, highlighting the highest ability to perform work. Future studies can focus on the utilization of low-temperature waste heat, which is 66% of the total, for example, the Organic Ranking Cycle technology and the heat pump technology. • A Societal Waste Heat Accounting model quantified waste heat potential in China. • Waste heat potential occupies 42% of total primary energy input in 2018. • Most potential exists in the electricity generation and industry sectors. • Theoretically 26% of energy savings and carbon reductions by waste heat utilization. • The policy priority for the future is the utilization of waste heat below 100 °C. [ABSTRACT FROM AUTHOR]

For China to achieve carbon emissions peak and neutrality, the structural adjustment of both its economy and energy system is essential. In this study, a multi-objective optimization model based on the Input-Output approach is built to coordinate diverse policy targets vis-à-vis GDP growth, carbon emissions reduction, employment, and energy-saving of China from 2020 to 2030. The optimal structural adjustment pathways of China's economy, reflecting a high-resolution of available electricity generation technologies, under four policy preferences, are planned and the co-benefits and trade-offs among multiple policy targets are detected. Our results reveal that while the energy-saving preference is more likely to hinder GDP growth (by −190 trillion yuan) and employment levels (by −60 million jobs), however, this preference is conducive to carbon emissions reduction (by −2.6 billion tons). Furthermore, our findings reveal that although the low-carbon preference does not undermine employment levels, however, it will restrain GDP growth (by 109 trillion yuan). The integrated management of multiple policy targets would require the country's industrial structure to increase the proportion of low-carbon to total electricity generation to account for 71% by 2030 and the proportion of the services sector to the whole economy to account between 42% and 51% by 2030. • A multi-objective optimization model based on the Input-Output model is proposed. • The structural adjustment of economic sectors with fine-resolution power sectors is examined. • Coordinate contradictions caused by policy targets on economy-environment-employment. • Sectors that enable sustainability governance more balanced in reflecting three pillars are identified. [ABSTRACT FROM AUTHOR]

China relies heavily on coal for power generation, and the demand for coal in a country of this size makes China the world's largest carbon dioxide emitter; hence China is pursuing greener pathways for power generation. Importing shale gas in the form of LNG from Canada is one such pathway. It starts with the recovery of shale gas in Canada and its export to China. This paper quantifies well-to-wire (WTW) greenhouse gas (GHG) emissions per kilowatt hour (kWh) of Canadian shale gas-fuelled electricity in China through models. WTW emissions include emissions from recovery, processing, transmission, liquefaction, marine shipping, re-gasification, power plant operations, and electricity transmission and distribution. Four Canadian shale gas reserves – Montney, Horn River, Liard, and Cordova – are considered. The results show that the WTW GHG emissions of Canadian shale gas-fired combined cycle technology range from 567 to 610 gCO 2 /kWh (57–62% of the GHG emissions from China's present coal-fired electricity), and total well-to-port (WTP) GHG emissions (emissions from recovery, processing, and transmission to a liquefaction facility) range from 7.68 to 13.4 gCO 2e /MJ. Sensitivity analysis results show that venting emissions during raw gas processing, flaring rates during well completion, and lifetime productivity of the gas significantly influence WTP emissions. [ABSTRACT FROM AUTHOR]

The objective of this paper is to introduce geothermal energy resources, utilization, development roadmap, and government support in China. Over the last 20 years, China was the first place in the world in direct utilization of geothermal energy with total amount reaching 17,870 MWt in 2014, and with an increasing trend annually. Compared with the rapid increase of direct utilization, the development of geothermal power generation in China is not obvious in the past 40 years, with an installed capacity of 27.78 MWe, ranking 18th in the world at present. It is reported that geothermal heating area was up to 396 million square meters with an installed capacity of 1178 MWt in 2013. Research on HDR (hot dry rock) resources is in its infancy. Considering the recoverable coefficient of 2%, energy stored in HDR at a depth of 3.0–10.0 km is 4500 times the total energy consumption in China in 2013. In order to achieve sustainable development of geothermal energy in China, attention should be paid to the following aspects in the future: technology development of EGS (enhanced geothermal system), low cost and scale-up of geothermal power generation, cascade utilization in geothermal heating, and sustainable exploitation and utilization of geothermal reservoirs. [ABSTRACT FROM AUTHOR]

Operational efficiency analysis is the foundational work for the management policy adjustment of the electric power industry in China and many other countries, but it is difficult to conduct because of the system complexity. This research uses a network structure to simulate the operating process of this industry. Through introducing the dynamic slack-based measure algorithm into this structure, the operational efficiencies of the entire industry and each stage (power generation and transmission–distribution) in each period are evaluated. On this basis, extended methods are also designed to measure the factor efficiency and the technological gap of each group. The model is applied to China's electric power industry, and the following conclusions are drawn: (I) The operational efficiency levels of provinces and regions are relatively different. (II) Generally, the operational efficiency of the generation stage is significantly lower than that of the transmission–distribution stage. (III) Factors with efficiencies ranked from highest to lowest are capital, labor, and energy. (IV) Major policy implications include breaking down the barriers to prompt interprovincial electricity transmission, developing the energy storage industry, implementing the flexibility transformation of thermal power units, and reducing the cross subsidy to the residual electricity consumption. [Display omitted] • A dynamic network structure is used for operational efficiency analysis. • Extended methods are designed to measure the factor efficiency and the group gap. • The model is applied to China's electric power industry. • Key policy directions to improve the operational efficiency are recognized. [ABSTRACT FROM AUTHOR]

In the power sector, electricity transmission is highly linked with electricity generation. However, quite limited number of studies have considered the combined performance of electricity generation and transmission system. To do so, this study adopts network DEA models. To the best of our knowledge, the existing network DEA cross-efficiency models may suffer from one important drawback, since these models generally assume that DMUs are completely rational and neglect the potential effects of DMUs' risk attitudes that may play an important role in the evaluation process. To relax thisassumption, this study proposes a new type of network DEA prospect cross-efficiency models. To our knowledge, such work cannot be found in the existing studies. Empirically, this study focuses on the case of China's electricity generation-transmission system from 2010 to 2019. The main conclusions are summarized as follows. First, China succeeded in achieving an overall improvement with an annual growth rate of 2.84% during the analysis period. Second, within-group 2 was the most important driving factor affecting technology diffusion, accounting for 63.32% of the overall Gini coefficient. Finally, significant method heterogeneity has been confirmed among alternative DEA models, implying that method selection is important for modelers to perform empirical analysis. • We propose new network Data Envelopment Analysis prospect cross-efficiency models. • They combine network DEA with cross-efficiency evaluation and prospect theory. • They are used to evaluate China's electricity generation & transmission system. • Overall improvement in unified efficiency is found during 2010–2019. • Significant method heterogeneity has been confirmed among alternative DEA models. [ABSTRACT FROM AUTHOR]

Large numbers of China's thermal power plants are in water-stressed regions. Changes in the availability of water resources due to climate change may impact the vulnerability of regional and national electricity generation. Here we explore this vulnerability for coal-fired power units (CPUs) as the generation-type most exposed to climate risk. We find many plants are already experiencing water scarcity and 120–176 GW of capacity will be exposed to water scarcity for at least one additional month per year in the 2030s. In the absence of carbon capture and storage (CCS) the national useable capacity of CPUs will increase slightly, mainly due to an increase in water availability for power plants in northern China under all climate scenarios except RCP8.5. However, CCS systems have been identified as essential in China's national roadmap for carbon neutrality and their use represents high water requirements. The addition of CCS significantly exacerbates water vulnerability, leading to further useable-capacity reductions of 7.4–7.7%. We assess several adaptations and find that early retirement of power plants is most effective, with interregional power transmission also playing an important mitigating role. Our work highlights the need for improved awareness of water resources in electricity planning. • The water availability issues still exist for some recently built power plants. • 120–176 GW of capacity will be exposed to severer water scarcity in the 2030s. • Carbon capture and storage will lead to useable-capacity reductions of 7.4–7.7%. • Early retirement and improving power transmission can mitigate the vulnerability. • Adaptation options of vulnerability mitigation will face many challenges. [ABSTRACT FROM AUTHOR]

Electrolysis hydrogen generation technology is one of the feasible ways to alleviate the problem of wind electricity curtailment. One promising hydrogen value-added application is to blend hydrogen into the natural gas grid and sell it as the heat energy carrier. This paper aims to discuss the feasibility of a roadmap to urban energy internet with wind electricity-natural gas nexus. Firstly, a framework is raised to integrate wind electricity generation, electrolysis hydrogen generation, and hydrogen-natural gas blending systems. Secondly, a series of reasonable hydrogen supply profiles are provided based on annual electricity curtailment and realistic natural gas scheduling. Then, an energy optimisation model and a techno-economic model are applied to simulate the generation of electricity and hydrogen, as well as determine the most economical hydrogen supply scheme. Finally, a case study in the Beijing-Tianjin-Hebei region of China is taken to validate the benefits of the proposed roadmap. The preferred scheme is worked out with the net present value of 88.8 M$, including the economy configurations of the electricity-hydrogen hybrid generation system, as well as the hydrogen-natural gas blending plan. The results also indicate that annual electricity curtailment and annual carbon emission are decreased by 204 GWh (48.8%) and 40.2 kt (49.9%). • Raise a roadmap to urban energy internet with wind electricity-natural gas nexus. • Set a framework to integrate electrolysis hydrogen generation and blending systems. • Propose an overall optimisation model for economic and environmental analysis. • Hydrogen supply depends on wind electricity curtailment and natural gas scheduling. • The improved economic and environmental benefits in a real case are identified. [ABSTRACT FROM AUTHOR]

Focusing on the low recycling rate of low temperature waste heat in China's iron and steel industry, this study presented a technical solution recycling blast furnace slag flashing water sensible heat based on thermoelectric power generation. The physical and numerical models are established. The effects of some key parameters such as slag washing water temperature, the thermoelectric element length, the packing factor of the thermoelectric module and heat exchanger flow passage length on the performance of the thermoelectric power generation device are analyzed. The results showed that for blast furnace slag flushing water at 100 °C, water temperature drops 1.5 °C per meter, about 0.93 kW electrical energy can be produced per area and conversion efficiency of 2% can be achieved. The cost recovery period of the equipment is about 8 years. [ABSTRACT FROM AUTHOR]

Many empirical studies have examined the causal relationship between electricity consumption and economic growth. Given the significant role of China in global economic growth and electricity use, this study analyzes the multiple causal mechanisms underlying the electricity consumption-economic growth nexus in China using a structural equation model and comparing the nexus with national-level data from 1978 to 2019. This study contributes to the understanding of the direct and indirect causal mechanisms between the electricity consumption-economic growth nexus. We find: (1) the nexus has strengthened with time, and the direct and indirect effects from electricity consumption to economic growth have also increased with time; (2) indirect influences of electricity consumption on economic growth are stronger than the direct influence; and (3) increasing ecological awareness brought about by economic growth increases the demand for electricity generation from clean energy sources. Therefore, the Chinese government should formulate policies to facilitate high-quality electricity production to meet the increasing demand from economic growth. • SEM tests the causality between electric consumption and economic growth in China. • Causal mechanisms between electricity consumption and economic growth are compared. • The direct effect of electricity consumption on economic growth increases. • The effect of electricity development on ecological awareness increases with time. [ABSTRACT FROM AUTHOR]

Integrating renewables and reliable fossil fuels in power generation is considered as one of the most promising and efficient strategy to solve carbon emissions and renewables uncertainties. In this paper, a new hybrid solar-wind-gas system fully considering natural gas and renewables cooperative complementarity in electric power generation is proposed, which is capable of achieving an equilibrium between benefits and reliability. A multi-objective optimization model simultaneously considering total income and power supply-demand deviation is then developed to obtain the best possible scheduling strategies under twelve natural scenarios, with ϵ -constraint method and fuzzy satisfying approach utilized. A real case from Golmud, China clearly demonstrates that the complementarity in this hybrid power system can effectively realize economic-reliable equilibrium. Specifically, the maximum total economic benefits can reach 31 176 × 103CNY in summer, and natural gas can provide a 100% supplementary power to ensure system reliability. Renewable power generation shows higher economical efficiency, so the highest benefits of 10 903 × 103CNY occur in sunny summer days, when renewable power output ratio is up to 68.84%. Meanwhile, natural gas, as a reliable energy source, has a higher complementary advantage over renewable energy, and its maximum change rate can be up to 14.54% which is almost 10 times of wind power. • A hybrid solar-wind-gas electric power generation scheduling optimization under renewable uncertainties is proposed. • The complementarity of solar, wind and natural gas power in electricity generation is fully analyzed. • An economic-reliable equilibrium in hybrid power generation is determined using multi-objective model. • Twelve typical scheduling scenarios with trapezoidal fuzzy numbers are established to solve renewable energy uncertainties. • A real case from China proves the practicality and effectiveness of the hybrid solar-wind-gas power generation system. [ABSTRACT FROM AUTHOR]

Abstract: Retrofitting existing power plants for CO2 capture poses numerous constraints. The layout of the original process and the structure of the existing equipment cause various special problems in the design process as well as influence system performance. In view of these, this paper carries out process simulations, characteristic analysis, and system integration of CO2 capture based on an existing typical coal-fired power plant in China with supercritical parameters. The main constraints encountered in decarburized retrofitting of the existing power plants using monoethanolamine solution are analyzed. In addition, several special system integration schemes for CO2 capture in an existing 600 MW power generation unit are put forward. The results reveals that, due to the constraints in the layout of the original process and the structure of the existing equipment, efficiency penalty of CO2 capture in an existing power plant will be as high as 13.73%-points, higher than a newly redesigned power plant by 3.70%-points. And through special system integrations, the efficiency of such retrofitting existing power plant can increase by 4.15%-points. The research of this paper may provide feasible technology solutions for the decarburized retrofitting of existing power plants and promote CCS (CO2 capture and storage) technologies into application. [Copyright &y& Elsevier]

Abstract: A novel comprehensive utilization system of oil shale involving retort subsystem, combustion subsystem, electricity generation and ash processing subsystem is recommended for Huadian oil shale. To ensure the thermal balance and stable operation of the whole system, part of non-condensable gases from retort process, as auxiliary fuel, are introduced into a combustor connected before the CFB furnace. The system performance is simulated using ASPEN software tool in this paper. The influence of retorting temperature, residence time, temperature and pressure of the CFB furnace, content of oil shale for combustion, content of non-condensable gases for combustion on the system performance are discussed. In order to explore advantages of this system, a retort system and a combustion system are investigated. The results show that increasing retorting temperature, residence time, pressure of CFB furnace and content of non-condensable gases for combustion has positive significant effect on improving the total profit and the output energy efficient of the comprehensive utilization system. The solid heat carrier technology is more adaptable for this system. Compared with other utilization modes for oil shale, the comprehensive utilization system has higher utilization efficiency of oil shale resources, more diversified products, lower pollutants emission and higher total profit. [Copyright &y& Elsevier]

Abstract: Photovoltaic (PV) power has a huge resource of supply, wide range of usage, and low impact on environment and it is considered as a key factor of the supply mix in the future for China. PV power is still in its infancy in China. It has higher cost than coal-fired power, and needs policy support. In recent years, China has launched a series of policies to stimulate PV power. These policies, however, are temporal, mainly because the total additional investment to make PV power grid parity is uncertain. After a brief review on current status of PV power development in China, this paper applies learning curve theory to study the cost reduction trends of polycrystalline silicon PV cells - main components of large-scale PV (LS-PV) power generation, then sets different scenarios to estimate time and the total learning cost of PV power’s grid parity. MESSAGE model is also applied to make a comparable estimation of the future PV installation in China. The results show that long-term subsidy policy for PV power is feasible in China with the rising cost of coal-fired power, but aggressive subsidy policy is not very efficient. [Copyright &y& Elsevier]

Abstract: This paper analyzes the electricity saving potential of China’s power generation industry using the macroeconomic approach. In order to forecast future electricity saving potential, we apply cointegration techniques combined with risk analysis model to estimate future (APRauxiliary power ratio) of the national power plant. It is found that power structure, technology and AUH (annual utilization hours) of power equipment are all important macro-factors that affect APR. The high proportion of thermal power is the main reason for the high APR. However, the improvements in technology and AUH help to reduce the APR. Therefore, implementation of the “Replacing Small Units with Large ones” policy and promotion of large-capacity high-parameter units have contributed to electricity conservation in China’s power generation industry. With constraints of relevant energy policies, the scenario analysis concludes that electricity saving potential at the power generation side appears more significant and could reach over 40 TWh (terawatt hour) in 2020. Finally, using the results of the scenario analysis, future policy priorities for energy conservation in China’s power industry are assessed in this paper. [Copyright &y& Elsevier]

Abstract: With China’s rapid economic development and urbanization process, cities are facing great challenges for tackling anthropogenic climate change. In this paper we present features, trajectories and driving forces for energy-related greenhouse gas (GHG) emissions from four Chinese mega-cities (Beijing, Tianjin, Shanghai and Chongqing) during 1995–2009. First, top-down GHG inventories of these four cities, including direct emissions (scope 1) and emissions from imported electricity (scope 2) are presented. Then, the driving forces for the GHG emission changes are uncovered by adopting a time serial LMDI decomposition analysis. Results indicate that annual GHG emission in these four cities exceeds more than 500 million tons and such an amount is still rapidly growing. GHG emissions are mainly generated from energy use in industrial sector and coal-burning thermal power plants. The growth of GHG emissions in four mega-cities during 1995–2009 is mainly due to economic activity effect, partially offset by improvements in carbon intensity. Besides, the proportion of indirect GHG emission from imported energy use (scope 2) keeps growing, implying that big cities are further dependent on energy/material supplies from neighboring regions. Therefore, a comprehensive consideration on various perspectives is needed so that different stakeholders can better understand their responsibilities on reducing total GHG emissions. [Copyright &y& Elsevier]

Abstract: After tremendous growth of wind power generation capacity in recent years, China now has 44.7 GW of wind-derived power. Despite the recent growth rates and promises of a bright future, two important issues - the capability of the grid infrastructure and the availability of backup systems - must be critically discussed and tackled in the medium term. The study shows that only a relatively small share of investment goes towards improving and extending the electricity infrastructure which is a precondition for transmitting clean wind energy to the end users. In addition, the backup systems are either geographically too remote from the potential wind power sites or currently financially infeasible. Finally, the introduction of wind power to the coal-dominated energy production system is not problem-free. Frequent ramp ups and downs of coal-fired plants lead to lower energy efficiency and higher emissions, which are likely to negate some of the emission savings from wind power. The current power system is heavily reliant on independently acting but state-owned energy companies optimizing their part of the system, and this is partly incompatible with building a robust system supporting renewable energy technologies. Hence, strategic, top-down co-ordination and incentives to improve the overall electricity infrastructure is recommended. [Copyright &y& Elsevier]

Abstract: This paper investigates the relationship between the green economy and green jobs in China through the following question: Can the current GHG mitigation policies in China’s power generation sector bring more jobs to China? Using both analytical and input–output models this paper analyzes the direct and indirect employment impacts of two main mitigation policies in the power generation sector. This paper proves that the above-mentioned question is not simple. Mitigation policies in China’s power generation sector from 2006 to 2009 caused a total of 44 thousand net jobs losses. However, as the share of renewable energy that has an indirect employment impacts increased in 2010, the policies from 2006 to 2010 actually resulted in 472 thousand net job gains. This paper asserts that to ensure the co-existence of green economy and green jobs in China’s power generation sector, policy makers should further promote solar PV, biomass and wind technologies. In 2010, for every one percent increase in the share of solar PV generation there could be a 0.68% increase in total employment in China, larger than any other power generation technology. Finally, this paper argues that a matching educational system and personnel structure is also needed. [Copyright &y& Elsevier]

Abstract: Wind energy has been well recognized as a renewable resource in electricity generation, which is environmentally friendly, socially beneficial and economically competitive. For proper and efficient evaluation of wind energy, a hybrid Seasonal Auto-Regression Integrated Moving Average and Least Square Support Vector Machine (SARIMA–LSSVM) model is significantly developed to predict the mean monthly wind speed in Hexi Corridor. The design concept of combining the Seasonal Auto-Regression Integrated Moving Average (SARIMA) method with the Least Square Support Vector Machine (LSSVM) algorithm shows more powerful forecasting capacity for monthly wind speed prediction at wind parks, when compared with the single Auto-Regression Integrated Moving Average (ARIMA), SARIMA, LSSVM models and the hybrid Auto-Regression Integrated Moving Average and Support Vector Machine (ARIMA–SVM) model. To verify the developed approach, the monthly data from January 2001 to December 2006 in Mazong Mountain and Jiuquan are used for model construction and model testing. The simulation and hypothesis test results show that the developed method is simple and quite efficient. [Copyright &y& Elsevier]

Abstract: Forecasts of energy demand, the fuel mix meeting that demand and the associated emissions are a key requirement for informed energy planning and policy decisions to ensure energy security and address climate change. While there have been many studies on China focusing on the short and medium term (to 2020 and 2050) there is little in the literature focusing on the long term (to 2100). This paper seeks to address those gaps on sectoral energy demands and emissions on long term by following a two-stage approach. It develops key energy indicators on useful energy demand, transport mobility and end use fuel demand for various sectors. The main drivers of these indicators are socio-economic parameters. The indicators are used to project energy service demands and emissions forward for China in TIMES G5 model at least cost approach. The results from this reference scenario suggest that China will require approximately 4 Gtoe of primary energy, by the end of the 21st century to deliver 3 Gtoe final energy consumption, 10 PWh of electricity generation, 1.3 Gtoe of energy imports, which will results in 10 Gt CO2 emissions. [ABSTRACT FROM AUTHOR]

Abstract: China''s total installed electrical power capacity reached 700GW by the end of 2007 and is predicted to surpass 900GW in 2010. The rapid increase in energy demand and increasing global warming have both pushed China to change its current electrical power structure where coal power accounts for nearly 75% of the total electric power generation. China has already become the world''s largest solar water heater producer and user. However, there is still much to be done in the solar thermal power field before its commercialization. Solar thermal power technologies including solar power towers, solar parabolic trough concentrators, solar dish/stirling systems, linear Fresnel reflectors, and solar chimneys have been studied in China since the 1980s. A 10kW dish/stirling project was funded by the Ministry of Science and Technology (MOST) during 2000–2005 with a 1MW solar power tower and research of trough concentrator metal–glass evacuated tubes supported during 2006–2010. This paper describes a continued solar thermal power development roadmap in China in 5-year intervals between 2006 and 2025. [Copyright &y& Elsevier]

Abstract: Among renewable energy resources, bioenergy is one of the fastest growth energy alternatives with tremendous potential in China. The thermal, physical, and biological processes of conversion of biomass yield a number of products and can be obtained as gases, liquids, solid fuels, and electricity as well as a variety of chemicals. Various bioenergy technologies that have been developed are at the fundamental research, demonstration, and commercialization stages. This review concentrates on the processes that are attracting the most attention in China. This paper presents the important roles bioenergy plays in China. Firstly, the application status of bioenergy technologies are introduced, including biogas, fuel ethanol, biodiesel, and power generation at the commercialization stage. Then, the current research progresses are analyzed of ethanol derived from lignocellulose, sweet sorghum and cassava, biodiesel from jatropha, biomass briquetting, synthesized fuels and pyrolysis technologies at the fundamental research and demonstration stages. Finally, it is concluded that the key areas for developing bioenergy for the future are the exploitation of new biomass resources and R&D in biofuels from non-food biomass resources, as well as the development of commercialization methods suitable for developing countries. [Copyright &y& Elsevier]

Abstract: In Copenhagen climate conference China government promised that China would cut down carbon intensity 40–45% from 2005 by 2020. CET (carbon emissions trading) is an effective tool to reduce emissions. But because CET is not fully implemented in China up to now, how to design it and its potential impact are unknown to us. This paper studies the potential impact of introduction of CET on China’s power sector and discusses the impact of different allocation options of allowances. Agent-based modeling is one appealing new methodology that has the potential to overcome some shortcomings of traditional methods. We establish an agent-based model, CETICEM (CET Introduced China Electricity Market), of introduction of CET to China. In CETICEM, six types of agents and two markets are modeled. We find that: (1) CET internalizes environment cost; increases the average electricity price by 12%; and transfers carbon price volatility to the electricity market, increasing electricity price volatility by 4%. (2) CET influences the relative cost of different power generation technologies through the carbon price, significantly increasing the proportion of environmentally friendly technologies; expensive solar power generation in particular develops significantly, with final proportion increasing by 14%. (3) Emission-based allocation brings about both higher electricity and carbon prices than by output-based allocation which encourages producers to be environmentally friendly. Therefore, output-based allocation would be more conducive to reducing emissions in the Chinese power sector. [ABSTRACT FROM AUTHOR]

Abstract: The fast-growing Chinese economy will inevitably need more and more energy. This not only makes China''s energy shortage situation severer, but also causes more and more worries from the countries all over the world, especially those developed countries. In this paper, China''s energy state is analyzed and the influences of promoting new socialist countryside construction on China''s energy source problem and its energy strategy making are discussed. It is stressed in this paper that in drawing the national energy development plan, it is of vital importance to take the impacts of new socialist countryside construction on energy production, supply and consumption into consideration. Traditional mineral energy supply that has been used for towns and cities should not be simply copied to solve the energy problem in countryside construction. The best choice for combating the huge energy increase resulted from speeding up the countryside construction is promoting utilization of biomass and solar energy and various advanced energy technologies. To make the utilization of biomass and solar energy and various advanced energy technologies in countryside, the government should give necessary technical and financial supports. [Copyright &y& Elsevier]

Abstract: We present the energy use situation in Hong Kong from 1979 to 2006. The primary energy requirement (PER) nearly tripled during the 28-year period, rising from 195,405 to 566,685TJ, about two-third of which was used for electricity generation. The residential and commercial sectors are the two largest electricity end-users with an average annual growth rate of 5.9% and 7.4%, respectively. The monthly consumption in these two sectors shows distinct seasonal variations mainly due to changes in the air-conditioning requirements, which are affected by the prevailing weather conditions. Principal component analysis of five major climatic variables—dry-bulb temperature, wet-bulb temperature, global solar radiation, clearness index and wind speed—was conducted. Measured sector-wide electricity consumption was correlated with the corresponding two principal components determined using multiple regression technique. The regression models could give a very good indication of the annual electricity use (largely within a few percents), but individual monthly estimation could differ by up to 24%. It was also found that the climatic indicators determined appeared to show a slight increasing trend during the 28-year period indicating a subtle, but gradual change of climatic conditions that might affect future air-conditioning requirements. [Copyright &y& Elsevier]

Energy production has become an important concern because excessive coal and oil use for electricity generation and consumption in developing economies threaten the global environment. Past research mainly focuses on energy consumption, while there is a scarcity of models on the energy and electricity production-environmental pollution nexus in the Environmental Kuznets Curve literature. As an initial attempt, the paper examined the simultaneous impact of electricity production and electricity consumption on carbon dioxide emissions in one of the top energy-consuming, energy-producing, and carbon-emitting nations (China). The study applied the Zivot and Andrew tests to check the stationarity of the series with structural breaks. The autoregressive distributed lag (ARDL) method was to compute long-run coefficients using two separate models: Model 1 (total electricity production and environmental pollution) and Model 2 (total electricity consumption and environmental pollution) were considered. The results showed that electricity production and electricity consumption significantly contributed to environmental pollution in the short- and long-run. Apart from validating the EKC hypothesis (inverted-U-shaped curve) in the short- and long-run, the estimation demonstrated that agriculture value-added mitigated the environmental pollution. The paper offers important policy implications. [Display omitted] • Environmental effects of electricity (production and consumption) were examined for China. • Simultaneous equation modeling framework was used. • Electricity production increased CO 2 emissions in China. • Electricity consumption increased CO 2 emissions in China. • Agriculture value added decreased CO 2 emissions in China. [ABSTRACT FROM AUTHOR]

Co-location of wind and tidal current turbines (WTs/TCTs) is a new way to improve the economy and reliability of electricity generation from renewable energy sources. In this paper, an optimization model for determining the configuration of a co-located wind/tidal current farm (WF/TCF) is proposed. The objectives include the minimization of the system levelized cost of energy (LCOE) and the maximization of the system average power supply reliability (APSR). In the planning area, there are certain zones where there are important restrictions which do not allow WTs/TCTs to be installed. These are called forbidden zones. When deciding the feasible area in the optimization, the complement of the forbidden zones in the planning area is used. The optimization problem is formulated as a coordinate model (CM) and a grid model (GM), both solved by the multi-swarm optimization (MSO) algorithm. The proposed approach is tested in an offshore area of Zhejiang province, China. Simulation results indicate that the co-location of a WF/TCF is an economic-technical efficient approach to harvest marine renewable energy. Also, the MSO algorithm outperforms its counterparts, the particle swarm optimization (PSO) and the discrete particle swarm optimization (DPSO) algorithms, in solving the CM and the GM of the WF/TCF layout optimization problem. • The layout of a co-located WF/TCF is optimized. • The optimization objectives are the minimization of LCOE and the maximization of APSR. • The forbidden zones in the planning area are considered in the optimization. • The optimization problem is formulated as a CM and a GM, respectively. • The MSO algorithm is compared with the PSO and the DPSO algorithms. [ABSTRACT FROM AUTHOR]

The clean and efficient energy production from municipal solid waste (MSW) is highly desirable due to increasing energy demand and environmental concerns. In this study, four incineration- (S1) and gasification-based (S2 with combustion boiler, S3 with gas turbine/combined cycle and S4 with internal combustion engine) MSW treatments were compared using methods of environmental life cycle assessment (LCA) and exergetic life cycle assessment (ELCA). LCA was applied to measure the environmental performances and ELCA was supplemented to reflect the thermodynamics efficiencies. Afterwards, cumulative degree of perfection (CDP) and abatement exergy (AbatCExC) efficiency of the considered systems were also calculated to determine the imperfection and environmental sustainability of the processes. Results showed that gasification-based systems were effective to mitigate the environmental impacts of acidification, nutrient enrichment, and photochemical ozone formation potential, but caused higher global warming impacts. The S3 system exhibited the best performance from both environmental and exergetic perspective, due to its high net efficiency of electricity generation and low exhaust emission into air. Results from ELCA indicated that the rest two gasification-based systems (S2 and S4) were inefficient as compared to MSW direct incineration, mainly due to auxiliary energy consumption for MSW pretreatment and more conversion steps. The CDP and AbatCExC of the systems in descending order was expressed as S3 system > S1 system > S2 system > S4 system. • Four incineration and gasification WtE systems were modeled and compared. • Gasification gas turbine/CC showed best environmental and exergetic performance. • Gasification systems showed low environmental burdens but high GW potential. • MSW direct incineration showed high CExC and CDP efficiency. [ABSTRACT FROM AUTHOR]

Energy, water, and materials are interconnected in several ways. Increasing demand for resources combined with environmental, availability, accessibility, and security risks associated with their supply are raising concerns for their future sustainable management. Resources nexus and CO 2 emissions in China have been analysed using a dynamic material flow-stock model for 10 electricity generation technologies (EGT) and 21 materials. The analysis includes 10 scenarios, combining energy scenarios; National Development and Reform Commission (NDRC) and International Energy Agency (IEA-450), and scenarios for EGT materials content and energy, water, and CO 2 intensities. Cumulative energy, water, and CO 2 emissions associated with EGT materials production in NDRC scenario are double those in IEA-450 scenario. Annual energy required for materials is expected to be between 2.3% and 3.4% of annual EG. Highest water, energy, and CO 2 are related to PV and wind in NDRC scenario and hydropower and PV in IEA-450 scenario. Required Fe and concrete for EGT is much higher than Al, however energy, water, and CO 2 emissions associated with Al are either higher or slightly lower than Fe and concrete. Careful selection of EGT and their materials is significant to reduce EG impacts, and considering resources nexus is significant for future integrated resources policies. • Material-Energy-Water-Carbon nexus in China's EG system has been analysed using two energy scenarios. • Energy required for materials is expected to be 2.3% to 3.4% of generated electricity in China. • Highest amounts of water, energy, and CO 2 are related to PV solar and hydropower. • Energy, water, and CO 2 emissions related to Al are higher or slightly lower than Fe and concrete. • Careful selection of EGT and their materials is significant to reduce EG impacts. [ABSTRACT FROM AUTHOR]