Solar power energy in some countries can be the most potential renewable energy to overcome lack of energy and environmental problems. Indonesia is one of the examples. One of the promising cities to install photovolt...Solar power energy in some countries can be the most potential renewable energy to overcome lack of energy and environmental problems. Indonesia is one of the examples. One of the promising cities to install photovoltaic (PV) systems is Makassar, which has average 5.83 kWh/m2/day of solar irradiance (Meyta, 2011). However, until 2016, there is still no solar panel installation in Makassar (PLN, 2015). In addition, general lack of research in assessing potential of PV systems in Makassar makes PV system difficult to develop. This study therefore set out to assess PV system potential in Makassar which its objectives are to determine 1) total available area for rooftop and large-scale PV systems in Makassar, 2) economy feasibility and 3) environmental impact due to PV installation. Three cases have been analyzed in this study, first, PV systems for residential rooftop, second, PV systems for large-scale (mega solar) in Makassar, and third, PV systems for large scale in outside Makassar and radius 20 km from center of Makassar. ArcGIS10.3 software is carried out to estimate available area for PV installation. Furthermore, RetScreen 4 software was used to conduct PV system capacity and its energy yield and to evaluate economy analysis such as internal rate of return and cost of energy. As the result, the total available area for residential rooftop PV system is evaluated to be 13.8 km2, which potential installed capacity is estimated to be 2044 MW. Total available area for large-scale PV system in Makassar and outside Makassar are 19.3 km2 and 231.3 km2, which estimated 851 MW and 10,179 MW of installed capacity, respectively.展开更多
Alongside the pursuit of high energy density and long service life,the urgent demand for low-temperature performance remains a long-standing challenge for a wide range of Li-ion battery applications,such as electric v...Alongside the pursuit of high energy density and long service life,the urgent demand for low-temperature performance remains a long-standing challenge for a wide range of Li-ion battery applications,such as electric vehicles,portable electronics,large-scale grid systems,and special space/seabed/military purposes.Current Li-ion batteries suffer a major loss of capacity and power and fail to operate normally when the temperature decreases to-20℃.This deterioration is mainly attributed to poor Li-ion transport in a bulk carbonated ester electrolyte and its derived solid–electrolyte interphase(SEI).In this mini-review discussing the limiting factors in the Li-ion diffusion process,we propose three basic requirements when formulating electrolytes for low-temperature Liion batteries:low melting point,poor Liþaffinity,and a favorable SEI.Then,we briefly review emerging progress,including liquefied gas electrolytes,weakly solvating electrolytes,and localized high-concentration electrolytes.The proposed novel electrolytes effectively improve the reaction kinetics via accelerating Li-ion diffusion in the bulk electrolyte and interphase.The final part of the paper addresses future challenges and offers perspectives on electrolyte designs for low-temperature Li-ion batteries.展开更多
The state-of-art lithium-ion batteries(LIBs)have achieved great commercial success during the past decades.The intercalation mechanisms in graphite anode and lithium transition metal oxide enabled its long-term stabil...The state-of-art lithium-ion batteries(LIBs)have achieved great commercial success during the past decades.The intercalation mechanisms in graphite anode and lithium transition metal oxide enabled its long-term stability in organic electrolytes.The classic electrolyte formula of lithium hexafluorophosphate(Li PF6)in carbonate solvents provided a benign solid electrolyte interphase(SEI)on the electrode surface.Subsequent researches on materials and electrolytes have improved the electrochemical stability and energy density for LIBs.Nevertheless,their adoptions,especially in electric vehicles and power grid have been obstructed owing to the safety concerns and environmental impact.The flammable carbonate solvents are easy to trigger fire and cause cell failure.The common used LiPF6 is sensitive to moisture which increases much difficulty to eliminate trace water in practical application.展开更多
Sodium-ion batteries have been achieving widespread attentions in grid-scale electrical energy storage systems owing to their earth abundant resources[1].However,the energy-density ceiling from cathode materials has b...Sodium-ion batteries have been achieving widespread attentions in grid-scale electrical energy storage systems owing to their earth abundant resources[1].However,the energy-density ceiling from cathode materials has been one of primary factors precluding the further practical applications of sodium-ion batteries[2].展开更多
Communications network damage resulting from a large disaster causes difficulties in the ability to rapidly understand the current situation and thus make appropriate decisions towards mitigating problems,such as wher...Communications network damage resulting from a large disaster causes difficulties in the ability to rapidly understand the current situation and thus make appropriate decisions towards mitigating problems,such as where to send and dispense emergency supplies.The research outlined in this paper focuses on the rapid construction of a network after a disaster occurs.This study suggests ZigBee and geographic information systems(GIS)technologies to resolve these problems and provide an effective communication system.The experimental results of the ZigBee network system are presented,examples are provided of the mapping and analysis undertaken using GIS for the disaster-stricken area of Tsukuba City,Japan,and the communications node arrangements are determined for this region.These results demonstrate the effectiveness of establishing such a communications system for supporting efforts to relieve disaster-damaged areas.展开更多
The electric field environment under high-voltage direct current(HVDC)transmission lines is an important design consideration.In the wireless sensor networks for electric field measurement system under the HVDC transm...The electric field environment under high-voltage direct current(HVDC)transmission lines is an important design consideration.In the wireless sensor networks for electric field measurement system under the HVDC transmission lines,it is necessary to obtain the electric field distribution with multiple sensors.The accurate localisation of sensing nodes is essential to the analysis of measurement results.However,most current techniques are limited to constant measurement environment with fixed and known path-loss exponent.Here,the authors report a localisation method based on received signal strength indication with unknown path-loss exponent for the localisation of one-dimensional linear topology wireless networks in the electric field measurement system.The optimisation method is utilised to obtain the optimal pass-loss parameter without involving the previous environment parameters.Afterwards,simulations are employed to demonstrate the feasibility and the effectiveness of the proposed method by comparing with other methods.展开更多
文摘Solar power energy in some countries can be the most potential renewable energy to overcome lack of energy and environmental problems. Indonesia is one of the examples. One of the promising cities to install photovoltaic (PV) systems is Makassar, which has average 5.83 kWh/m2/day of solar irradiance (Meyta, 2011). However, until 2016, there is still no solar panel installation in Makassar (PLN, 2015). In addition, general lack of research in assessing potential of PV systems in Makassar makes PV system difficult to develop. This study therefore set out to assess PV system potential in Makassar which its objectives are to determine 1) total available area for rooftop and large-scale PV systems in Makassar, 2) economy feasibility and 3) environmental impact due to PV installation. Three cases have been analyzed in this study, first, PV systems for residential rooftop, second, PV systems for large-scale (mega solar) in Makassar, and third, PV systems for large scale in outside Makassar and radius 20 km from center of Makassar. ArcGIS10.3 software is carried out to estimate available area for PV installation. Furthermore, RetScreen 4 software was used to conduct PV system capacity and its energy yield and to evaluate economy analysis such as internal rate of return and cost of energy. As the result, the total available area for residential rooftop PV system is evaluated to be 13.8 km2, which potential installed capacity is estimated to be 2044 MW. Total available area for large-scale PV system in Makassar and outside Makassar are 19.3 km2 and 231.3 km2, which estimated 851 MW and 10,179 MW of installed capacity, respectively.
文摘Alongside the pursuit of high energy density and long service life,the urgent demand for low-temperature performance remains a long-standing challenge for a wide range of Li-ion battery applications,such as electric vehicles,portable electronics,large-scale grid systems,and special space/seabed/military purposes.Current Li-ion batteries suffer a major loss of capacity and power and fail to operate normally when the temperature decreases to-20℃.This deterioration is mainly attributed to poor Li-ion transport in a bulk carbonated ester electrolyte and its derived solid–electrolyte interphase(SEI).In this mini-review discussing the limiting factors in the Li-ion diffusion process,we propose three basic requirements when formulating electrolytes for low-temperature Liion batteries:low melting point,poor Liþaffinity,and a favorable SEI.Then,we briefly review emerging progress,including liquefied gas electrolytes,weakly solvating electrolytes,and localized high-concentration electrolytes.The proposed novel electrolytes effectively improve the reaction kinetics via accelerating Li-ion diffusion in the bulk electrolyte and interphase.The final part of the paper addresses future challenges and offers perspectives on electrolyte designs for low-temperature Li-ion batteries.
文摘The state-of-art lithium-ion batteries(LIBs)have achieved great commercial success during the past decades.The intercalation mechanisms in graphite anode and lithium transition metal oxide enabled its long-term stability in organic electrolytes.The classic electrolyte formula of lithium hexafluorophosphate(Li PF6)in carbonate solvents provided a benign solid electrolyte interphase(SEI)on the electrode surface.Subsequent researches on materials and electrolytes have improved the electrochemical stability and energy density for LIBs.Nevertheless,their adoptions,especially in electric vehicles and power grid have been obstructed owing to the safety concerns and environmental impact.The flammable carbonate solvents are easy to trigger fire and cause cell failure.The common used LiPF6 is sensitive to moisture which increases much difficulty to eliminate trace water in practical application.
文摘Sodium-ion batteries have been achieving widespread attentions in grid-scale electrical energy storage systems owing to their earth abundant resources[1].However,the energy-density ceiling from cathode materials has been one of primary factors precluding the further practical applications of sodium-ion batteries[2].
文摘Communications network damage resulting from a large disaster causes difficulties in the ability to rapidly understand the current situation and thus make appropriate decisions towards mitigating problems,such as where to send and dispense emergency supplies.The research outlined in this paper focuses on the rapid construction of a network after a disaster occurs.This study suggests ZigBee and geographic information systems(GIS)technologies to resolve these problems and provide an effective communication system.The experimental results of the ZigBee network system are presented,examples are provided of the mapping and analysis undertaken using GIS for the disaster-stricken area of Tsukuba City,Japan,and the communications node arrangements are determined for this region.These results demonstrate the effectiveness of establishing such a communications system for supporting efforts to relieve disaster-damaged areas.
基金supported in part by China Aviation Science Foundation(2015ZD51051)National Natural Science Foundation of China(61273165)SGCC Science and Technology Project of China(GY71-16-010).
文摘The electric field environment under high-voltage direct current(HVDC)transmission lines is an important design consideration.In the wireless sensor networks for electric field measurement system under the HVDC transmission lines,it is necessary to obtain the electric field distribution with multiple sensors.The accurate localisation of sensing nodes is essential to the analysis of measurement results.However,most current techniques are limited to constant measurement environment with fixed and known path-loss exponent.Here,the authors report a localisation method based on received signal strength indication with unknown path-loss exponent for the localisation of one-dimensional linear topology wireless networks in the electric field measurement system.The optimisation method is utilised to obtain the optimal pass-loss parameter without involving the previous environment parameters.Afterwards,simulations are employed to demonstrate the feasibility and the effectiveness of the proposed method by comparing with other methods.
