To the year 2020, China will realize the target of increasing non-fossil generation to 15% of the total energy consumption. Speeding up power sources restructuring comes up as an arduous task during the 12^(th) Five-Y...To the year 2020, China will realize the target of increasing non-fossil generation to 15% of the total energy consumption. Speeding up power sources restructuring comes up as an arduous task during the 12^(th) Five-Year Plan period. In this article, the author outlines the principles of structure adjustment for various kinds of power sources, and points out the issues needing attention during the restructuring.展开更多
RES （renewable energy sources）, such as wind and photovoltaic power plants, suffer from their stochastic nature that is why their behavior on market is very delicate. In order to diversify risk, a concept of VPP （v...RES （renewable energy sources）, such as wind and photovoltaic power plants, suffer from their stochastic nature that is why their behavior on market is very delicate. In order to diversify risk, a concept of VPP （virtual power plant） has been developed. The VPP is composed of several RES, from which at least one of them is fully controllable. Because the production of noncontrollable RES can not be forecasted perfectly, therefore an optimal dispatch schedule within VPP is needed. To address this problem, an APSO （accelerated particle swarm optimization） is used to solve the constrained optimal dispatch problem within VPP. The experimental results show that the proposed optimization method provides high quality solutions while meeting constraints.展开更多
Energy-conservation based generation dispatching is the revolutionary change in operation mode which could reduce energy consumption and pollutant emissions, promote power industry restructuring, and achieve sustainab...Energy-conservation based generation dispatching is the revolutionary change in operation mode which could reduce energy consumption and pollutant emissions, promote power industry restructuring, and achieve sustainable development. Social benefit evaluation of the energy-conservation based generation dispatching under the new situation and environment has come into being as an important theoretical issue. A new scenario analysis based social benefit evluating method, which is implemented by comparing the energy., consumption and pollutant emissions of different scenarios defined by the key indicators, i.e., load factor and coal consumption structure, is proposed in the paper. Then the composition of social benefit is analyzed from the point of the dispatching mode and the coal consumption structure. The method proposed is of clear physical meaning. It is not only practical, but also applicable for the implementation of energy-conservation based generation dispatching in diffferent phases and with different goals.展开更多
Lithium (Li) metal is considered as the ultimate anode choice for developing next-generation high-energy batteries. However, the poor tolerance against moist air and the unstable solid electrolyte interphases (SEI) in...Lithium (Li) metal is considered as the ultimate anode choice for developing next-generation high-energy batteries. However, the poor tolerance against moist air and the unstable solid electrolyte interphases (SEI) induced by the intrinsic high reactivity of lithium bring series of obstacles such as the rigorous operating condition, the poor electrochemical performance, and safety anxiety of the cell, which to a large extent hinder the commercial utilization of Li metal anode. Here, an effective encapsulation strategy was reported via a facile drop-casting and a following heat-assisted cross-linking process. Benefiting from the inherent hydrophobicity and the compact micro-structure of the cross-linked poly(vinylidene-co-hex afluoropropylene) (PVDF–HFP), the as-encapsulated Li metal exhibited prominent stability toward moisture, as well corroborated by the evaluations both under the humid air at 25 °C with 30% relative humidity (RH) and pure water. Moreover, the encapsulated Li metal anode exhibits a decent electrochemical performance without substantially increasing the cell polarization due to the uniform and unblocked ion channels, which originally comes from the superior affinity of the PVDF–HFP polymer toward nonaqueous electrolyte. This work demonstrates a novel and valid encapsulation strategy for humiditysensitive alkali metal electrodes, aiming to pave the way for the large-scale and low-cost deployment of the alkali metal-based high-energy-density batteries.展开更多
The variation of the flux of energetic electrons in the magnetosphere has been proven to be strongly related to the solar wind speed. Observations of GEO orbit show that the flux of low-energy electrons is not only mo...The variation of the flux of energetic electrons in the magnetosphere has been proven to be strongly related to the solar wind speed. Observations of GEO orbit show that the flux of low-energy electrons is not only modulated by the solar wind speed, but, if a time delay is added, is also positively correlated to the flux of high-energy electrons. This feature provides a possible method to forecast the flux of high-energy electrons in GEO orbit. In this study, the correlations of the fluxes between the high-energy electrons and low-middle-energy electrons obtained at different L values and in different orbits are investigated to develop the application of this feature. Based on the analysis of long–term data observed by NOAA POES and GOES, the correlations between the fluxes of high-energy electrons and low–middle–energy electrons are good enough at different L values and in different orbits in quiet time, but this correlation is strongly affected by CME–driven geomagnetic storms.展开更多
With the increasing energy consumption of computing systems and the growing advocacy for green computing, energy efficiency has become one of the critical challenges in high-performance heterogeneous computing systems...With the increasing energy consumption of computing systems and the growing advocacy for green computing, energy efficiency has become one of the critical challenges in high-performance heterogeneous computing systems. Energy consumption can be reduced by not only hardware design but also software design. In this paper, we propose an energy-aware scheduling algorithm with equalized frequency, called EASEF, for parallel applications on heterogeneous computing systems. The EASEF approach aims to minimize the finish time and overall energy consumption. First, EASEF extracts the set of paths from an application. Then, it reconstructs the application based on the extracted set of paths to achieve a reasonable schedule. Finally, it adopts a progressive way to equalize the frequency of tasks to reduce the total energy consumption of systems. Randomly generated applications and two real-world applications are examined in our experiments. Experimental results show that the EASEF algorithm outperforms two existing algorithms in terms of makespan and energy consumption.展开更多
Consumers＇ electricity cost keeps increasing over the time in most countries across the world. The main reason is that importing electricity from generation plants far from a load center is relatively expensive, as c...Consumers＇ electricity cost keeps increasing over the time in most countries across the world. The main reason is that importing electricity from generation plants far from a load center is relatively expensive, as costs are paid not only for generation but also for energy loss and network use. To this end, it is more economi- cal to use electricity generated by local distributed generations. In order to reduce customers＇ electricity cost, a new economic dispatch of smart distribution networks is proposed. Economic dispatch of smart distribution network is to meet load demand with the least consumers＇ electricity cost considering distributed generators, while recognizing all operational limits of generation and transmission facilities in a distribution network. Case study shows that consumers＇ electricity cost can be reduced by about 200/o through economic dispatch of distri- bution network. Further, generation cost and emission of distribution network are reduced as well.展开更多
文摘To the year 2020, China will realize the target of increasing non-fossil generation to 15% of the total energy consumption. Speeding up power sources restructuring comes up as an arduous task during the 12^(th) Five-Year Plan period. In this article, the author outlines the principles of structure adjustment for various kinds of power sources, and points out the issues needing attention during the restructuring.
文摘RES （renewable energy sources）, such as wind and photovoltaic power plants, suffer from their stochastic nature that is why their behavior on market is very delicate. In order to diversify risk, a concept of VPP （virtual power plant） has been developed. The VPP is composed of several RES, from which at least one of them is fully controllable. Because the production of noncontrollable RES can not be forecasted perfectly, therefore an optimal dispatch schedule within VPP is needed. To address this problem, an APSO （accelerated particle swarm optimization） is used to solve the constrained optimal dispatch problem within VPP. The experimental results show that the proposed optimization method provides high quality solutions while meeting constraints.
文摘Energy-conservation based generation dispatching is the revolutionary change in operation mode which could reduce energy consumption and pollutant emissions, promote power industry restructuring, and achieve sustainable development. Social benefit evaluation of the energy-conservation based generation dispatching under the new situation and environment has come into being as an important theoretical issue. A new scenario analysis based social benefit evluating method, which is implemented by comparing the energy., consumption and pollutant emissions of different scenarios defined by the key indicators, i.e., load factor and coal consumption structure, is proposed in the paper. Then the composition of social benefit is analyzed from the point of the dispatching mode and the coal consumption structure. The method proposed is of clear physical meaning. It is not only practical, but also applicable for the implementation of energy-conservation based generation dispatching in diffferent phases and with different goals.
基金This work was supported by National Key Research and Development Program(2016YFA0202500)National Natural Science Foundation of China(21776019)Beijing Natural Science Foundation(L182021).
文摘Lithium (Li) metal is considered as the ultimate anode choice for developing next-generation high-energy batteries. However, the poor tolerance against moist air and the unstable solid electrolyte interphases (SEI) induced by the intrinsic high reactivity of lithium bring series of obstacles such as the rigorous operating condition, the poor electrochemical performance, and safety anxiety of the cell, which to a large extent hinder the commercial utilization of Li metal anode. Here, an effective encapsulation strategy was reported via a facile drop-casting and a following heat-assisted cross-linking process. Benefiting from the inherent hydrophobicity and the compact micro-structure of the cross-linked poly(vinylidene-co-hex afluoropropylene) (PVDF–HFP), the as-encapsulated Li metal exhibited prominent stability toward moisture, as well corroborated by the evaluations both under the humid air at 25 °C with 30% relative humidity (RH) and pure water. Moreover, the encapsulated Li metal anode exhibits a decent electrochemical performance without substantially increasing the cell polarization due to the uniform and unblocked ion channels, which originally comes from the superior affinity of the PVDF–HFP polymer toward nonaqueous electrolyte. This work demonstrates a novel and valid encapsulation strategy for humiditysensitive alkali metal electrodes, aiming to pave the way for the large-scale and low-cost deployment of the alkali metal-based high-energy-density batteries.
基金supported by the National Natural Science Foundation of China(Grant Nos.41374167,41074117&41374166)
文摘The variation of the flux of energetic electrons in the magnetosphere has been proven to be strongly related to the solar wind speed. Observations of GEO orbit show that the flux of low-energy electrons is not only modulated by the solar wind speed, but, if a time delay is added, is also positively correlated to the flux of high-energy electrons. This feature provides a possible method to forecast the flux of high-energy electrons in GEO orbit. In this study, the correlations of the fluxes between the high-energy electrons and low-middle-energy electrons obtained at different L values and in different orbits are investigated to develop the application of this feature. Based on the analysis of long–term data observed by NOAA POES and GOES, the correlations between the fluxes of high-energy electrons and low–middle–energy electrons are good enough at different L values and in different orbits in quiet time, but this correlation is strongly affected by CME–driven geomagnetic storms.
基金Project supported by the National Natural Science Foundation of China （Nos. 61133005, 61432005, 61370095, 61472124, and 61402400）
文摘With the increasing energy consumption of computing systems and the growing advocacy for green computing, energy efficiency has become one of the critical challenges in high-performance heterogeneous computing systems. Energy consumption can be reduced by not only hardware design but also software design. In this paper, we propose an energy-aware scheduling algorithm with equalized frequency, called EASEF, for parallel applications on heterogeneous computing systems. The EASEF approach aims to minimize the finish time and overall energy consumption. First, EASEF extracts the set of paths from an application. Then, it reconstructs the application based on the extracted set of paths to achieve a reasonable schedule. Finally, it adopts a progressive way to equalize the frequency of tasks to reduce the total energy consumption of systems. Randomly generated applications and two real-world applications are examined in our experiments. Experimental results show that the EASEF algorithm outperforms two existing algorithms in terms of makespan and energy consumption.
基金supported in part by The National High Technology Research and Development of China 863 Program(2012AA050201)
文摘Consumers＇ electricity cost keeps increasing over the time in most countries across the world. The main reason is that importing electricity from generation plants far from a load center is relatively expensive, as costs are paid not only for generation but also for energy loss and network use. To this end, it is more economi- cal to use electricity generated by local distributed generations. In order to reduce customers＇ electricity cost, a new economic dispatch of smart distribution networks is proposed. Economic dispatch of smart distribution network is to meet load demand with the least consumers＇ electricity cost considering distributed generators, while recognizing all operational limits of generation and transmission facilities in a distribution network. Case study shows that consumers＇ electricity cost can be reduced by about 200/o through economic dispatch of distri- bution network. Further, generation cost and emission of distribution network are reduced as well.
