This paper describes the results of cost-profit analysis related to interconnectors for Japan-Russia and JapanSouth Korea based on the Asia International Grid Connection Study Group 2^(nd) report. The Group has been e...This paper describes the results of cost-profit analysis related to interconnectors for Japan-Russia and JapanSouth Korea based on the Asia International Grid Connection Study Group 2^(nd) report. The Group has been established in 2016 for conducting research on international electric power networks in Asia from the viewpoint of technology, investment and legal framework. 2^(nd) report of the Group was published in June 2018, examining the profitability of an interconnectors between Japan and neighboring countries. The Group has calculated expected profit from operation of these interconnectors.The Group has categorized interconnector business into four models from the survey of preceding and current business on grids and interconnectors. To clarify profitability, expected internal rate of return(IRR) was calculated for each business model based on estimated investment cost for each route. When interconnector is dedicated to specific power plants or suppliers and electricity can be sold at Japan wholesale market at 2016-2017 price level, positive IRR levels are expected in case that Free on Board(FOB) price lower than 7 JPY/kWh. When the investment will be covered by electricity tariff by final consumers, tariff for consumers will just slightly increase by approximately 0.1 JPY/kWh.展开更多
In order to simultaneously improve the oxidation resistance and the electrical conductivity of solid oxide fuel cell(SOFC)interconnectors,a composite coating of Co–W/NiO was fabricated on ferritic stainless steel by ...In order to simultaneously improve the oxidation resistance and the electrical conductivity of solid oxide fuel cell(SOFC)interconnectors,a composite coating of Co–W/NiO was fabricated on ferritic stainless steel by composite deposition and pre-oxidation.Based on phase identification and microstructural analysis,the novel coating was confirmed to effectively suppress Cr diffusion to form a compact Cr-rich layer.Thus,the oxidation rate has been reduced to 9.46×10−15 g^(2)cm^(−4)s^(−1),which showed a imporvement of 56.4%in oxidation resistance.The area specific resistance value of Co–W/NiO coated steel was evaluated as 27.6 mΩcm^(2),much lower than that of Co–W coating as 53.38 mΩcm^(2),which is adequate for SOFC application.Furthermore,the mechanism of the improvement has been investigated that the addition of NiO led to the formation of Ni–Co spinels and Ni–W composites,which affected the surface microstructure of the coating.Thus,the composite Co–W/NiO coated ferritic stainless steel exhibited the optimal combination for oxidation resistance and electrical conductivity.展开更多
Decarbonizing the power sector is a necessary step towards a low-carbon future. Interconnecting power systems on different continents could be a method to contribute to such a future, by utilizing highly efficient ren...Decarbonizing the power sector is a necessary step towards a low-carbon future. Interconnecting power systems on different continents could be a method to contribute to such a future, by utilizing highly efficient renewable resources around the globe, while simultaneously providing additional benefits of power system integration. In this paper, we describe the process of constructing and simulating a global interconnected power system model with high technical and temporal resolution. Being the first of its kind on the global scale, this paper is designed to showcase the proof of concept as an intermediate step to a high resolution global model, by integrating an existing European power system model with the North-American continent. The work to date has been focused on testing the methodology and building up necessary knowledge to realistically simulate the functionality of a possible future global grid. Some initial results are analysed to support the viability of the model and the concept in general. Furthermore, key factors influencing the development and optimal performance of the global interconnected power system model are identified.展开更多
It is promising for metal especially ferritic stainless steel（FSS）to be used as interconnector when the solid oxide fuel cell（SOFC）is operated at temperature lower than 800℃.However,there are many challenges for ...It is promising for metal especially ferritic stainless steel（FSS）to be used as interconnector when the solid oxide fuel cell（SOFC）is operated at temperature lower than 800℃.However,there are many challenges for FSS such as anti-oxidant,poisoning to cathode and high area specific resistance（ASR）when using as SOFC interconnector.The effect of Cr content（12-30 mass%）in Fe-Cr alloys on thermal expansion coefficient（TEC）,oxidation resistance,microstructure of oxidation scale and ASR was investigated by thermo-gravimetry,scanning electron microscopy,energy dispersive spectroscopy and four-probe DC technique.The TEC of Fe-Cr alloys is（11-13）×10^（-6） K^（-1）,which excellently matches with other SOFC components.Alloys have excellent oxidation resistance when Cr content exceeds 22mass% because of the formation of chromium on the surface of alloy.The oxidation rate constants kdand ksdecrease rapidly with increasing the Cr content and then increase slowly when the Cr content is higher than 22mass%.The kinetic results indicate that Cr evaporation must be considered at high temperature for Fe-Cr alloys.After the alloys were oxidized in air at 800℃ for500 h,log（ASR/T）（Tis the absolute temperature）presents linear relationship with 1/T and the conduct activation energy is 0.6-0.8eV（Cr16-30）.Optimal Cr content is 22-26mass%considering the oxidation resistance and ASR.展开更多
This paper describes route designs and cost estimation for possible interconnections between Japan-Russia and between Japan-South Korea based on the Asia International Grid Connection Study Group 2^(nd) report. The Gr...This paper describes route designs and cost estimation for possible interconnections between Japan-Russia and between Japan-South Korea based on the Asia International Grid Connection Study Group 2^(nd) report. The Group has conducted a desktop study to design several cable routes as possible options. To optimize the route, the group studied a wide range of open data, regarding sea depth, fishery zones, geographic condition, available transmission capacity in connecting points inside Japan and so on. The result of desktop study shows that it is possible to keep sea depth for planned routes less than 300 m and length for most of designed routes is less than 600 km. Compare to existing undersea cables in Europe, proposed routes are not challenging from technical and geological viewpoints.The study shows that investment cost range, including cost for grid enhancement inside Japan, is from around 200 bn JPY to 600 bn JPY, depending on the routes. Annualized cost range is from around 8 to 24 bn JPY(for 25-year operation), which is not so large compare to 1800 bn JPY-average annual investment in transmission infrastructure by 10 power utilities in the past 23 years.展开更多
A 10-nm-thick molybdenum tri-oxide（MoO3） thin film was used as the interconnector layer in tandem organic lightemitting devices（OLEDs）.The tandem OLEDs with two identical emissive units consisting of N,N-bis（naph...A 10-nm-thick molybdenum tri-oxide（MoO3） thin film was used as the interconnector layer in tandem organic lightemitting devices（OLEDs）.The tandem OLEDs with two identical emissive units consisting of N,N-bis（naphthalen-1-yl）N,N-bis（phenyl）-benzidine（NPB） /tris（8-hydroxyquinoline） aluminum（Alq3） exhibited current efficiency-current density characteristics superior to the conventional single-unit devices.At 20 mA/cm2,the current efficiency of the tandem OLEDs using the interconnector layers of MoO3 thin film was about 4.0 cd/A,which is about twice that of the corresponding conventional single-unit device（1.8cd/A）.The tandem OLED showed a higher power efficiency than the conventional single-unit device for luminance over 1200cd/m2.The experimental results demonstrated that a MoO3 thin film with a proper thickness can be used as an effective interconnector layer in tandem OLEDs.Such an interconnector layer can be easily fabricated by simple thermal evaporation,greatly simplifying the device processing and fabrication processes required by previously reported interconnector layers.A possible explanation was proposed for the carrier generation of the MoO3 interconnector layer.展开更多
The amount of solar PV installed capacity has steadily increased to 44.5 GW at the end of FY2017,since the introduction of the Feed in Tariff(FiT)to Japan in 2012.On the other hand,since the first curtailment of solar...The amount of solar PV installed capacity has steadily increased to 44.5 GW at the end of FY2017,since the introduction of the Feed in Tariff(FiT)to Japan in 2012.On the other hand,since the first curtailment of solar PV was conducted on October 13th,2018 in the Kyushu area,the curtailment has been frequently executed including wind power after that.In this study,cross-regional interconnector and pumped hydro energy storage(PHES)are focused on mitigating curtailment.In Japan,there are 9 electric power areas which connected each other by cross-regional interconnectors.According to the historical operation,cross-regional interconnectors were secured as emergency flexible measures,but after the implicit auction was started from October 2018,it is used on merit order.Regarding a PHES in Japan,they have been built with nuclear power plants for several decades.Because the output of nuclear power generation is constant,so the PHES is used to absorb the surplus at nighttime when the demand declines.All nuclear power plants in Japan have been shut down after the accident at the Fukushima Daiichi Nuclear Power Plant following the Great East Japan Earthquake that occurred on March 11th,2011.There are several nuclear power plants that have been restarted(9 reactors,as of August 2019).In this study,the amount of curtailment for solar PV in the Kyushu area is sent to the Chugoku area using the cross-regional interconnector(Kanmon line).Then,the PHES in the Chugoku area is pumping with low price.Because the spot price in the market is low when the curtailment is executed.After that,the PHES is generating at night with high price when the solar PV is not generating.It makes a profit by the deference for the cost of pumping and the revenue of generating by the PHES.As a calculation result,for one week from May 2nd to 8th,2019,a profit becomes 152.2 million JPY(about 1.22 million EUR).For this purpose,it is necessary to raise the operation capacity of the cross-regional interconnector up to the rated capacity with the frequency control function of solar PV instead of the capacity to keep frequency in the event of an accident.This will allow the further introduction of solar PV in Japan.展开更多
As an interconnector of solid oxide fuel cell, La 1-x Ca x CrO 3( x =0 0～0 5) were prepared by sol gel method. The crystal structures of La 1-x Ca x CrO 3 at room temperature are the or...As an interconnector of solid oxide fuel cell, La 1-x Ca x CrO 3( x =0 0～0 5) were prepared by sol gel method. The crystal structures of La 1-x Ca x CrO 3 at room temperature are the orthorhombic perovskite GdFeO 3 type. XPS analysis indicates that chrome ions are in different valence state. The introduction of Ca 2+ into the lattice induces the oxidation of Cr 3+ to Cr 6+ . With x increasing, the amount of Cr 6+ increases. The present of the more Cr 6+ is one of the important factors that effect electric conductivity of La 1-x Ca x CrO 3.展开更多
Interconnector is a critical component to construct solid oxide cells (SOCs) stack. Oxidation of metallic interconnectors and Cr poisoning caused by oxidation are important factors that lead to long-term performance d...Interconnector is a critical component to construct solid oxide cells (SOCs) stack. Oxidation of metallic interconnectors and Cr poisoning caused by oxidation are important factors that lead to long-term performance degradation of SOCs. Coating on the interconnector surface is an important approach to inhibit the oxidation and Cr migration of the interconnector. Herein, (La0.75Sr0.25)0.95MnO3–δ (LSM) and Mn1.5Co1.5O4 (MCO) are used to fabricate the coatings of interconnector. Two advanced thermal spray technology, atmospheric plasma spraying (APS) and low-pressure plasma spray (LPPS), are adopted for the coating preparation. The electrochemical performance, rising and cooling cycle stability, and Cr diffusion inhibition performance of the coatings are tested and evaluated. The result indicates that MCO can generate more uniform and denser coatings than LSM. In addition, MCO coatings prepared by LPPS shows the best electrochemical performance, rising and cooling cycle stability, and Cr diffusion inhibition. The initial area specific resistance (ASR) is 0.0027 Ω·cm2 at 800 °C. After 4 cooling cycle tests, the ASR increases to 0.0032 Ω·cm2 but lower than other samples. Meanwhile, the relative intense of Cr at the interface of SUS430 with MCO coatings fabricated by LPPS is lower than that of MCO fabricated by APS after 4 rising and cooling cycle operations, showing more favorable Cr diffusion inhibition performance.展开更多
By utilizing a two-step process to express the charge generation and separation mechanism of the transition metal oxides （TMOs） interconnector layer, a numerical model was proposed for tandem organic light emitting ...By utilizing a two-step process to express the charge generation and separation mechanism of the transition metal oxides （TMOs） interconnector layer, a numerical model was proposed for tandem organic light emitting diodes （OLEDs） with a TMOs thin film as the interconnector layer. This model is valid not only for an n-type TMOs interconnector layer, but also for a p-type TMOs interconnector layer. Based on this model, the influences of different carrier injection barriers at the interface of the electrode/organic layer on the charge generation ability of interconnector layers were studied. In addition, the distribution characteristics of carrier concentration, electric field intensity and potential in the device under different carrier injection barriers were studied. The results show that when keeping one carrier injection barrier as a constant while increasing another carrier injection barrier, carri- ers injected into the device were gradually decreased, the carrier generation ability of the interconnector layer was gradually reduced, the electric field intensity at the interface of the organic/electrode was gradually enhanced, and the electric field distribution became nearly linear： the voltage drops in two light units gradually became the same. Meanwhile, the carrier injection ability decreased as another carrier injection barrier increased. The simulation re- sults agree with the experimental data. The obtained results can provide us with a deep understanding of the work mechanism of TMOs-based tandem OLEDs.展开更多
文摘This paper describes the results of cost-profit analysis related to interconnectors for Japan-Russia and JapanSouth Korea based on the Asia International Grid Connection Study Group 2^(nd) report. The Group has been established in 2016 for conducting research on international electric power networks in Asia from the viewpoint of technology, investment and legal framework. 2^(nd) report of the Group was published in June 2018, examining the profitability of an interconnectors between Japan and neighboring countries. The Group has calculated expected profit from operation of these interconnectors.The Group has categorized interconnector business into four models from the survey of preceding and current business on grids and interconnectors. To clarify profitability, expected internal rate of return(IRR) was calculated for each business model based on estimated investment cost for each route. When interconnector is dedicated to specific power plants or suppliers and electricity can be sold at Japan wholesale market at 2016-2017 price level, positive IRR levels are expected in case that Free on Board(FOB) price lower than 7 JPY/kWh. When the investment will be covered by electricity tariff by final consumers, tariff for consumers will just slightly increase by approximately 0.1 JPY/kWh.
基金supported by Hubei Natural Science Foundation of Hubei(2023AFB111).
文摘In order to simultaneously improve the oxidation resistance and the electrical conductivity of solid oxide fuel cell(SOFC)interconnectors,a composite coating of Co–W/NiO was fabricated on ferritic stainless steel by composite deposition and pre-oxidation.Based on phase identification and microstructural analysis,the novel coating was confirmed to effectively suppress Cr diffusion to form a compact Cr-rich layer.Thus,the oxidation rate has been reduced to 9.46×10−15 g^(2)cm^(−4)s^(−1),which showed a imporvement of 56.4%in oxidation resistance.The area specific resistance value of Co–W/NiO coated steel was evaluated as 27.6 mΩcm^(2),much lower than that of Co–W coating as 53.38 mΩcm^(2),which is adequate for SOFC application.Furthermore,the mechanism of the improvement has been investigated that the addition of NiO led to the formation of Ni–Co spinels and Ni–W composites,which affected the surface microstructure of the coating.Thus,the composite Co–W/NiO coated ferritic stainless steel exhibited the optimal combination for oxidation resistance and electrical conductivity.
文摘Decarbonizing the power sector is a necessary step towards a low-carbon future. Interconnecting power systems on different continents could be a method to contribute to such a future, by utilizing highly efficient renewable resources around the globe, while simultaneously providing additional benefits of power system integration. In this paper, we describe the process of constructing and simulating a global interconnected power system model with high technical and temporal resolution. Being the first of its kind on the global scale, this paper is designed to showcase the proof of concept as an intermediate step to a high resolution global model, by integrating an existing European power system model with the North-American continent. The work to date has been focused on testing the methodology and building up necessary knowledge to realistically simulate the functionality of a possible future global grid. Some initial results are analysed to support the viability of the model and the concept in general. Furthermore, key factors influencing the development and optimal performance of the global interconnected power system model are identified.
基金funded by Ministry of Science and Technology of China(2012CB215405)Fundamental Research Funds for Central Universities of China(FRF-TP-15-052A3)Chinese Postdoctoral Science Foundation(2014M560046)
文摘It is promising for metal especially ferritic stainless steel（FSS）to be used as interconnector when the solid oxide fuel cell（SOFC）is operated at temperature lower than 800℃.However,there are many challenges for FSS such as anti-oxidant,poisoning to cathode and high area specific resistance（ASR）when using as SOFC interconnector.The effect of Cr content（12-30 mass%）in Fe-Cr alloys on thermal expansion coefficient（TEC）,oxidation resistance,microstructure of oxidation scale and ASR was investigated by thermo-gravimetry,scanning electron microscopy,energy dispersive spectroscopy and four-probe DC technique.The TEC of Fe-Cr alloys is（11-13）×10^（-6） K^（-1）,which excellently matches with other SOFC components.Alloys have excellent oxidation resistance when Cr content exceeds 22mass% because of the formation of chromium on the surface of alloy.The oxidation rate constants kdand ksdecrease rapidly with increasing the Cr content and then increase slowly when the Cr content is higher than 22mass%.The kinetic results indicate that Cr evaporation must be considered at high temperature for Fe-Cr alloys.After the alloys were oxidized in air at 800℃ for500 h,log（ASR/T）（Tis the absolute temperature）presents linear relationship with 1/T and the conduct activation energy is 0.6-0.8eV（Cr16-30）.Optimal Cr content is 22-26mass%considering the oxidation resistance and ASR.
文摘This paper describes route designs and cost estimation for possible interconnections between Japan-Russia and between Japan-South Korea based on the Asia International Grid Connection Study Group 2^(nd) report. The Group has conducted a desktop study to design several cable routes as possible options. To optimize the route, the group studied a wide range of open data, regarding sea depth, fishery zones, geographic condition, available transmission capacity in connecting points inside Japan and so on. The result of desktop study shows that it is possible to keep sea depth for planned routes less than 300 m and length for most of designed routes is less than 600 km. Compare to existing undersea cables in Europe, proposed routes are not challenging from technical and geological viewpoints.The study shows that investment cost range, including cost for grid enhancement inside Japan, is from around 200 bn JPY to 600 bn JPY, depending on the routes. Annualized cost range is from around 8 to 24 bn JPY(for 25-year operation), which is not so large compare to 1800 bn JPY-average annual investment in transmission infrastructure by 10 power utilities in the past 23 years.
基金Project supported by the Doctoral Foundation of the Ministry of Education of China (Grant No. 20100171110025)the State Key Laboratory of Optoelectronic Materials and Technologies,China (Grant No. 2010-RC-3-1)the Fundamental Research Funds for the Central Universities,China (Grant No. 09lgpy25)
文摘A 10-nm-thick molybdenum tri-oxide（MoO3） thin film was used as the interconnector layer in tandem organic lightemitting devices（OLEDs）.The tandem OLEDs with two identical emissive units consisting of N,N-bis（naphthalen-1-yl）N,N-bis（phenyl）-benzidine（NPB） /tris（8-hydroxyquinoline） aluminum（Alq3） exhibited current efficiency-current density characteristics superior to the conventional single-unit devices.At 20 mA/cm2,the current efficiency of the tandem OLEDs using the interconnector layers of MoO3 thin film was about 4.0 cd/A,which is about twice that of the corresponding conventional single-unit device（1.8cd/A）.The tandem OLED showed a higher power efficiency than the conventional single-unit device for luminance over 1200cd/m2.The experimental results demonstrated that a MoO3 thin film with a proper thickness can be used as an effective interconnector layer in tandem OLEDs.Such an interconnector layer can be easily fabricated by simple thermal evaporation,greatly simplifying the device processing and fabrication processes required by previously reported interconnector layers.A possible explanation was proposed for the carrier generation of the MoO3 interconnector layer.
文摘The amount of solar PV installed capacity has steadily increased to 44.5 GW at the end of FY2017,since the introduction of the Feed in Tariff(FiT)to Japan in 2012.On the other hand,since the first curtailment of solar PV was conducted on October 13th,2018 in the Kyushu area,the curtailment has been frequently executed including wind power after that.In this study,cross-regional interconnector and pumped hydro energy storage(PHES)are focused on mitigating curtailment.In Japan,there are 9 electric power areas which connected each other by cross-regional interconnectors.According to the historical operation,cross-regional interconnectors were secured as emergency flexible measures,but after the implicit auction was started from October 2018,it is used on merit order.Regarding a PHES in Japan,they have been built with nuclear power plants for several decades.Because the output of nuclear power generation is constant,so the PHES is used to absorb the surplus at nighttime when the demand declines.All nuclear power plants in Japan have been shut down after the accident at the Fukushima Daiichi Nuclear Power Plant following the Great East Japan Earthquake that occurred on March 11th,2011.There are several nuclear power plants that have been restarted(9 reactors,as of August 2019).In this study,the amount of curtailment for solar PV in the Kyushu area is sent to the Chugoku area using the cross-regional interconnector(Kanmon line).Then,the PHES in the Chugoku area is pumping with low price.Because the spot price in the market is low when the curtailment is executed.After that,the PHES is generating at night with high price when the solar PV is not generating.It makes a profit by the deference for the cost of pumping and the revenue of generating by the PHES.As a calculation result,for one week from May 2nd to 8th,2019,a profit becomes 152.2 million JPY(about 1.22 million EUR).For this purpose,it is necessary to raise the operation capacity of the cross-regional interconnector up to the rated capacity with the frequency control function of solar PV instead of the capacity to keep frequency in the event of an accident.This will allow the further introduction of solar PV in Japan.
文摘As an interconnector of solid oxide fuel cell, La 1-x Ca x CrO 3( x =0 0～0 5) were prepared by sol gel method. The crystal structures of La 1-x Ca x CrO 3 at room temperature are the orthorhombic perovskite GdFeO 3 type. XPS analysis indicates that chrome ions are in different valence state. The introduction of Ca 2+ into the lattice induces the oxidation of Cr 3+ to Cr 6+ . With x increasing, the amount of Cr 6+ increases. The present of the more Cr 6+ is one of the important factors that effect electric conductivity of La 1-x Ca x CrO 3.
文摘Interconnector is a critical component to construct solid oxide cells (SOCs) stack. Oxidation of metallic interconnectors and Cr poisoning caused by oxidation are important factors that lead to long-term performance degradation of SOCs. Coating on the interconnector surface is an important approach to inhibit the oxidation and Cr migration of the interconnector. Herein, (La0.75Sr0.25)0.95MnO3–δ (LSM) and Mn1.5Co1.5O4 (MCO) are used to fabricate the coatings of interconnector. Two advanced thermal spray technology, atmospheric plasma spraying (APS) and low-pressure plasma spray (LPPS), are adopted for the coating preparation. The electrochemical performance, rising and cooling cycle stability, and Cr diffusion inhibition performance of the coatings are tested and evaluated. The result indicates that MCO can generate more uniform and denser coatings than LSM. In addition, MCO coatings prepared by LPPS shows the best electrochemical performance, rising and cooling cycle stability, and Cr diffusion inhibition. The initial area specific resistance (ASR) is 0.0027 Ω·cm2 at 800 °C. After 4 cooling cycle tests, the ASR increases to 0.0032 Ω·cm2 but lower than other samples. Meanwhile, the relative intense of Cr at the interface of SUS430 with MCO coatings fabricated by LPPS is lower than that of MCO fabricated by APS after 4 rising and cooling cycle operations, showing more favorable Cr diffusion inhibition performance.
基金supported by the National Natural Science Foundation of China(Nos.11265013,11264033)the Research Fund for the Doctoral Program of Higher Education of China(No.20110211110005)the Science Research Foundation of Tianshui Normal University(No.TSA1108)
文摘By utilizing a two-step process to express the charge generation and separation mechanism of the transition metal oxides （TMOs） interconnector layer, a numerical model was proposed for tandem organic light emitting diodes （OLEDs） with a TMOs thin film as the interconnector layer. This model is valid not only for an n-type TMOs interconnector layer, but also for a p-type TMOs interconnector layer. Based on this model, the influences of different carrier injection barriers at the interface of the electrode/organic layer on the charge generation ability of interconnector layers were studied. In addition, the distribution characteristics of carrier concentration, electric field intensity and potential in the device under different carrier injection barriers were studied. The results show that when keeping one carrier injection barrier as a constant while increasing another carrier injection barrier, carri- ers injected into the device were gradually decreased, the carrier generation ability of the interconnector layer was gradually reduced, the electric field intensity at the interface of the organic/electrode was gradually enhanced, and the electric field distribution became nearly linear： the voltage drops in two light units gradually became the same. Meanwhile, the carrier injection ability decreased as another carrier injection barrier increased. The simulation re- sults agree with the experimental data. The obtained results can provide us with a deep understanding of the work mechanism of TMOs-based tandem OLEDs.
