To investigate the overall performance of reverse energy bypass scramjet,firstly a variable spe⁃cific heat method combined with a chemical balance calculation module for combustion products were used to es⁃tablish a b...To investigate the overall performance of reverse energy bypass scramjet,firstly a variable spe⁃cific heat method combined with a chemical balance calculation module for combustion products were used to es⁃tablish a benchmark scramjet performance evaluation model.Based on the test data of typical flying point of Mach 7 with the altitude of 29 km,the reliability of the model was verified.The deviations of parameters such as the to⁃tal pressure loss of combustor between the model and the test data were analyzed.Furtherly,an analytical method for post-combustion magnetohydrodynamic power generation was established;by embedding the above method into the overall performance evaluation model,performance prediction considering the power generation effect was realized.Finally,based on the above model,variety regulations of the inlet and the outlet parameters of the power generation channel and performance parameters including the engine specific impulse and the unit thrust under different enthalpy extraction ratios and load factors were analyzed.It could be concluded that the model can reliably predict the variations of key parameters.As the value of the load factor increases,the value of the conduc⁃tivity required to reach the specified enthalpy extraction ratio first decreases and then increases,which is approxi⁃mately parabolic.In order to reduce the demand for the gas conductivity for MHD power generation,the load fac⁃tor should be around 0.5.When the load factor is 0.4 and the magnetic induction intensity is 2.5 T,if the enthalpy extraction ratio reaches 0.5%,the engine specific impulse performance reduces about 3.58%.展开更多
This study explores off-grid power generation business models in the Lao People's Democratic Republic(Lao PDR),with the objective of identifying viable pathways to expand energy access in rural and underserved reg...This study explores off-grid power generation business models in the Lao People's Democratic Republic(Lao PDR),with the objective of identifying viable pathways to expand energy access in rural and underserved regions.The research aims to analyze and evaluate various business models in terms of their technical,economic,and social viability within the unique geographic and policy context of Lao PDR.There are two level of the research objectives:High Level Objectives(HLO)and Concreted Research Objectives(CRO).For HLO is that an appropriated off-grid power generation business model for Laos supports the Lao PDR Government’s commitment to promote an inclusive green growth development agenda that ensures lowered GHG emissions and increased energy efficiency.The Lao PDR National Determined Contribution(NDC)to the United Nations Framework Convention on Climate Change(UNFCCC)notes the country’s ambitious plans to lower energy consumption and reduce GHG emissions.While the CRO are focused on learning strategies,regulation and practical lessons from other countries the ASEAN region on the off-grid development and business model.To analyze and investigate the environmental strategy of business model under external and internal context and related and considered factors.And finally,this is to conclude and recommend the off-grid power generation business model as the research conclusion,which will become a support mechanism for the companies to operate consistently over many years into the future according to ambitious goal for supplying modern and save energy for rural families by 2030.展开更多
In the original publication,mistakenly first and corresponding affiliation is given as:Thermoelectricity Technology Center,Hangzhou Dahe Thermo-Magnetics Co.Ltd,Hangzhou 310053,ChinaThe correct first and corresponding...In the original publication,mistakenly first and corresponding affiliation is given as:Thermoelectricity Technology Center,Hangzhou Dahe Thermo-Magnetics Co.Ltd,Hangzhou 310053,ChinaThe correct first and corresponding affiliation is:State Key Laboratory of Silicon Materials,School of Materials Science and Engineering,Zhejiang University,Hangzhou 310027,China.展开更多
In this study,the power generation difference between the east-west and the north-south orientation of the vertically installed heterojunction solar cell(HJT)modules was deeply discussed.East-west oriented HJT module ...In this study,the power generation difference between the east-west and the north-south orientation of the vertically installed heterojunction solar cell(HJT)modules was deeply discussed.East-west oriented HJT module has 30%higher power generation,especially in desert photovoltaic(PV)with a bimodal distribution.While the south-north one has a single peak,the same as normal PV modules.Vertical power generation technology of HJT also has less land occupation,which is of great significance for optimizing the design of photovoltaic systems.展开更多
With the proposed carbon-neutrality targets,intermittent renewable energy will become increasingly significant for the power sector in the future.It is vital to study its development paths,particularly for wind power ...With the proposed carbon-neutrality targets,intermittent renewable energy will become increasingly significant for the power sector in the future.It is vital to study its development paths,particularly for wind power and photovoltaics,while considering constraints on diffusion potential.Using learning curves,dynamic programming,and Bass models,this study analyzes technological diffusion trends to determine the most cost-effective development route for intermittent renewable energy power generation in China by 2060.This study simplifies reality by examining the individual diffusion processes of wind and photovoltaic power,focusing on the self-diffusion characteristics of the two technologies.The study assumes that self-diffusion is the primary driver of future development and describe the influence of multiple factors.The study finds that supportive policies are key drivers of development in the early stages of intermittent renewable energy deployment,especially for photovoltaics.The current diffusion scale of photovoltaics has a greater positive impact on its future development than that of wind power due to lower costs.In the long term,the phased goal for 2030 is projected to be met ahead of schedule,and the majority of future intermittent renewable energy output is expected to come from photovoltaics.The rapid development phases of photovoltaic and wind power conclude at similar times,but the maximum diffusion potential of photovoltaics is higher than that of wind power.Investment constraints and technological levels affect the initial and middle phases of the development path,but their effects are limited.The capacity of the power grid remains the key constraint in the entire research field.展开更多
With the continuous adjustment of the energy structure,photovoltaic(PV)power generation projects are increasing,playing a crucial role in promoting the application of clean energy.However,the current audit of complete...With the continuous adjustment of the energy structure,photovoltaic(PV)power generation projects are increasing,playing a crucial role in promoting the application of clean energy.However,the current audit of completed final accounts for photovoltaic power generation projects faces many challenges,such as incomplete institutional processes,scattered archive management materials,inadequate digital intelligence systems,and insufficient analysis of final account amounts.Based on this,this article aims to deeply analyze these issues and propose targeted audit suggestions to standardize the construction and audit work of photovoltaic power generation projects and promote the sustainable and healthy development of the photovoltaic power generation business.展开更多
This study investigates the Maximum Power Point Tracking(MPPT)control method of offshore windphotovoltaic hybrid power generation system with offshore crane-assisted.A new algorithm of Global Fast Integral Sliding Mod...This study investigates the Maximum Power Point Tracking(MPPT)control method of offshore windphotovoltaic hybrid power generation system with offshore crane-assisted.A new algorithm of Global Fast Integral Sliding Mode Control(GFISMC)is proposed based on the tip speed ratio method and sliding mode control.The algorithm uses fast integral sliding mode surface and fuzzy fast switching control items to ensure that the offshore wind power generation system can track the maximum power point quickly and with low jitter.An offshore wind power generation system model is presented to verify the algorithm effect.An offshore off-grid wind-solar hybrid power generation systemis built in MATLAB/Simulink.Compared with other MPPT algorithms,this study has specific quantitative improvements in terms of convergence speed,tracking accuracy or computational efficiency.Finally,the improved algorithm is further analyzed and carried out by using Yuankuan Energy’s ModelingTech semi-physical simulation platform.The results verify the feasibility and effectiveness of the improved algorithm in the offshore wind-solar hybrid power generation system.展开更多
This paper develops a high time-resolution optimal power generation mix model in its time resolution of 10 minutes on 365 days by linear programming technique. The model allows us to analyse the massive deployment of ...This paper develops a high time-resolution optimal power generation mix model in its time resolution of 10 minutes on 365 days by linear programming technique. The model allows us to analyse the massive deployment of photovoltaic system and wind power generation in power system explicitly considering those short-term output variation. PV （photovoltaic） and wind output are estimated, employing meteorological database. Simulation results reveal that variable fluctuation derived from a high penetration level of those renewables is controlled by quick load following operation of natural gas combined cycle power plant, pumped-storage hydro power, stationary NAS （sodium and sulfur） battery and the output suppression control of PV and wind. It additionally turns out that the operational configuration of those technologies for the renewable variability differs significantly depending on those renewable output variations in each season and solving the seasonal electricity imbalance as well as the daily imbalance is important if variable renewables are massively deployed.展开更多
On the basis of introducing clean power generation technologies, the author calculated and analyzed the investment, economy and environmental protection of these technologies, posed his views of giving the priorities ...On the basis of introducing clean power generation technologies, the author calculated and analyzed the investment, economy and environmental protection of these technologies, posed his views of giving the priorities to the development of supercritical and ultra-supercritical pressure coal-fired power generation technologies and taking vigorous action to nuclear power generation technology within the following 5-10 years, exploiting wind power within the following 10-15 years, and suggested that the installed capacity of nuclear power reach 80-100 GW and that of wind power reach 50-80 GW by 2020.展开更多
This paper discusses the potential and prospect of building-integrated photovoltaics (BIPV) for solar electrical power generation in China.The BIPV technology has been identified as the most economical renewable energ...This paper discusses the potential and prospect of building-integrated photovoltaics (BIPV) for solar electrical power generation in China.The BIPV technology has been identified as the most economical renewable energy resource to contribute to world electrical energy demand for protecting environment from reduced fossil fuel consumption.The available solar energy resource of 14 cities and the potential power generation from PV claddings in buildings in China were estimated.The economical analysis of BIPV application is discussed.It is found that the potential is significant and the government should play an important role in its development.展开更多
Through a great many qualitative and quantitative analyses, this paperstudies the development of gas power in China in the coming ten years based oninvestigations of more than one year. Some good advices are suggested...Through a great many qualitative and quantitative analyses, this paperstudies the development of gas power in China in the coming ten years based oninvestigations of more than one year. Some good advices are suggested toinvestors and decision-makers, such as the advantages and disadvantages ofpower generation using natural gas, development plans of local power grids, andproblems necessary to be noted and solved.[展开更多
This paper presents a new power generation structure that can provide DC energy for passive UHF RFID with high sensitivity and high efficiency. The structure is designed with 0.18μm standard CMOS technology, includin...This paper presents a new power generation structure that can provide DC energy for passive UHF RFID with high sensitivity and high efficiency. The structure is designed with 0.18μm standard CMOS technology, including two charge pumps,a current reference, and a group of bias circuits. Low-voltage performance is improved thanks to the bias structure,which eliminates the threshold voltage drop and body-effect of conventional circuits. A 350mV minimum input level is required to generate a 1.5V power supply for a 100k~ load with power conversion efficiency （PCE） of 22%. PCE up to 29.8% is achieved with a 60kΩ load. Simulation results show that the new circuit is superior to conventional charge pumps.展开更多
No matter from the economic perspective, or from the social perspective, to gradually achieve sustainable development, will need to attach importance to the construction of the energy system, give priority to the use ...No matter from the economic perspective, or from the social perspective, to gradually achieve sustainable development, will need to attach importance to the construction of the energy system, give priority to the use of renewable energy, but gradually increase in population, people's life gradually improve environment, represented by oil nonrenewable resources have been in a state of being long-term overexploitation. In order to meet the later development demand for energy, it is necessary to pay attention to the application of renewable energy, and solar energy is a kind of clean, environmental and renewable energy, so people gradually pay attention to the application of solar energy. Solar energy can be applied in many fields, such as the popular solar oven in the past, but now through solar photovoltaic power generation becomes the application trend of renewable energy in the future. This paper analyzes the application status of solar photovoltaic power generation technology, and describes the future development trend for reference.展开更多
Lignocellulosic biomass has attracted great interest in recent years for energy production due to its renewability and carbon-neutral nature.There are various ways to convert lignocellulose to gaseous,liquid and solid...Lignocellulosic biomass has attracted great interest in recent years for energy production due to its renewability and carbon-neutral nature.There are various ways to convert lignocellulose to gaseous,liquid and solid fuels via thermochemical,chemical or biological approaches.Typical biomass derived fuels include syngas,bio-gas,bio-oil,bioethanol and biochar,all of which could be used as fuels for furnace,engine,turbine or fuel cells.Direct biomass fuel cells mediated by various electron carriers provide a new direction of lignocellulose conversion.Various metal and non-metal based carriers have been screened for mediating the electron transfer from biomass to oxygen thus generating electricity.The power density of direct biomass fuel cells can be over 100 mW cm^(-2),which shows promise for practical applications.Lignocellulose and its isolated components,primarily cellulose and lignin,have also been paid considerable attention as sustainable carbonaceous materials for preparation of electrodes for supercapacitors,lithium-ion batteries and lithium-sulfur batteries.In this paper,we have provided a state-of-the-art review on the research progress of lignocellulosic biomass as feedstock and materials for power generation and energy storage focusing on the chemistry aspects of the processes.It was recommended that process integration should be performed to reduce the cost for thermochemical and biological conversion of lignocellulose to biofuels,while efforts should be made to increase efficiency and improve the properties for biomass fuelled fuel cells and biomass derived electrodes for energy storage.展开更多
This paper presents a preliminary experimental investigation on magnetohydrodynamic （MHD） power generation using seeded supersonic argon flow as working fluid. Helium and argon are used as driver and driven gas resp...This paper presents a preliminary experimental investigation on magnetohydrodynamic （MHD） power generation using seeded supersonic argon flow as working fluid. Helium and argon are used as driver and driven gas respectively in a shock tunnel. Equilibrium contact surface operating mode is used to obtain high temperature gas, and the conductivity is obtained by adding seed K2CO3 powder into the driven section. Under the conditions of nozzle inlet total pressure being 0.32 MPa, total temperature 6 504 K, magnetic field density about 0.5 T and nozzle outlet velocity 1 959 m/s, induction voltage and short-circuit current of the segmentation MHD power generation channel are measured, and the experimental results agree with theoretical calculations; the average conductivity is about 20 S/m calculated from characteristics of voltage and current. When load factor is 0.5, the maximum power density of the MHD power generation channel reaches 4.797 1 MW/m3, and the maximum enthalpy extraction rate is 0.34%. Finally, the principle and method of indirect testing for gas state parameters are derived and analyzed.展开更多
Hot dry rock(HDR)is a kind of clean energy with significant potential.Since the 1970s,the United States,Japan,France,Australia,and other countries have attempted to conduct several HDR development research projects to...Hot dry rock(HDR)is a kind of clean energy with significant potential.Since the 1970s,the United States,Japan,France,Australia,and other countries have attempted to conduct several HDR development research projects to extract thermal energy by breaking through key technologies.However,up to now,the development of HDR is still in the research,development,and demonstration stage.An HDR exploration borehole(with 236℃ at a depth of 3705 m)was drilled into Triassic granite in the Gonghe Basin in northwest China in 2017.Subsequently,China Geological Survey(CGS)launched the HDR resources exploration and production demonstration project in 2019.After three years of efforts,a sequence of significant technological breakthroughs have been made,including the genetic model of deep heat sources,directional drilling and well completion in high-temperature hard rock,large-scale reservoir stimulation,reservoir characterization,and productivity evaluation,reservoir connectivity and flow circulation,efficient thermoelectric conversion,monitoring,and geological risk assessment,etc.Then the whole-process technological system for HDR exploration and production has been preliminarily established accordingly.The first power generation test was completed in November 2021.The results of this project will provide scientific support for HDR development and utilization in the future.展开更多
Due to growing concerns regarding climate change and environmental protection,smart power generation has become essential for the economical and safe operation of both conventional thermal power plants and sustainable...Due to growing concerns regarding climate change and environmental protection,smart power generation has become essential for the economical and safe operation of both conventional thermal power plants and sustainable energy.Traditional first-principle model-based methods are becoming insufficient when faced with the ever-growing system scale and its various uncertainties.The burgeoning era of machine learning(ML)and data-driven control(DDC)techniques promises an improved alternative to these outdated methods.This paper reviews typical applications of ML and DDC at the level of monitoring,control,optimization,and fault detection of power generation systems,with a particular focus on uncovering how these methods can function in evaluating,counteracting,or withstanding the effects of the associated uncertainties.A holistic view is provided on the control techniques of smart power generation,from the regulation level to the planning level.The benefits of ML and DDC techniques are accordingly interpreted in terms of visibility,maneuverability,flexibility,profitability,and safety(abbreviated as the“5-TYs”),respectively.Finally,an outlook on future research and applications is presented.展开更多
Magnetohydrodynamic (MHD) power generation with supersonic non-equilibrium plasma is demonstrated. Capacitively coupled radio frequency (RF) discharge (6 MHz, maximum continual power output of 200 W) was adopted to io...Magnetohydrodynamic (MHD) power generation with supersonic non-equilibrium plasma is demonstrated. Capacitively coupled radio frequency (RF) discharge (6 MHz, maximum continual power output of 200 W) was adopted to ionize the Mach number 3.5 (650 m/s), 0.023 kg/m(3) airflow. In a MHD channel of 16 mm x 10 mm x 20 mm, MHD open voltage of 10 V is realized in the magnetic field of 1.25 T, and power of 0.12 mW is extracted steadily and continuously in the magnetic field of 1 T. The reasons for limited power generation are proposed as: low conductivity of RF discharge; large touch resistance between MHD electrode and plasma; strong current eddies due to flow boundary layer. In addition, the cathode voltage fall is too low to have obvious effects on MHD power generation. (C) 2016 Chinese Society of Aeronautics and Astronautics. Production and hosting by Elsevier Ltd.展开更多
The supercritical CO_(2) Brayton cycle is considered a promising energy conversion system for Generation IV reactors for its simple layout,compact structure,and high cycle efficiency.Mathematical models of four Brayto...The supercritical CO_(2) Brayton cycle is considered a promising energy conversion system for Generation IV reactors for its simple layout,compact structure,and high cycle efficiency.Mathematical models of four Brayton cycle layouts are developed in this study for different reactors to reduce the cost and increase the thermohydraulic performance of nuclear power generation to promote the commercialization of nuclear energy.Parametric analysis,multi-objective optimizations,and four decision-making methods are applied to obtain each Brayton scheme’s optimal thermohydraulic and economic indexes.Results show that for the same design thermal power scale of reactors,the higher the core’s exit temperature,the better the Brayton cycle’s thermo-economic performance.Among the four-cycle layouts,the recompression cycle(RC)has the best overall performance,followed by the simple recuperation cycle(SR)and the intercooling cycle(IC),and the worst is the reheating cycle(RH).However,RH has the lowest total cost of investment(C_(tot))of$1619.85 million,and IC has the lowest levelized cost of energy(LCOE)of 0.012$/(kWh).The nuclear Brayton cycle system’s overall performance has been improved due to optimization.The performance of the molten salt reactor combined with the intercooling cycle(MSR-IC)scheme has the greatest improvement,with the net output power(W_(net)),thermal efficiencyη_(t),and exergy efficiency(η_(e))improved by 8.58%,8.58%,and 11.21%,respectively.The performance of the lead-cooled fast reactor combined with the simple recuperation cycle scheme was optimized to increase C_(tot) by 27.78%.In comparison,the internal rate of return(IRR)increased by only 7.8%,which is not friendly to investors with limited funds.For the nuclear Brayton cycle,the molten salt reactor combined with the recompression cycle scheme should receive priority,and the gas-cooled fast reactor combined with the reheating cycle scheme should be considered carefully.展开更多
Disaster-hit and/or un-electrifed remote areas usually have electricity accessibility issues and an abundance of plant-derived debris and wood from destroyed wooden structures;this can be potentially addressed by empl...Disaster-hit and/or un-electrifed remote areas usually have electricity accessibility issues and an abundance of plant-derived debris and wood from destroyed wooden structures;this can be potentially addressed by employing a decentralized ultrasmall biomass-fed gasifcation power generating system.This paper presents an assessment of the technical viability of an ultra-small gasifcation system that utilizes densifed carbonized wood pellets/briquettes.The setup was run continuously for 100 h.A variety of biomass was densifed and carbonized by harnessing fugitive heat sources before charging into the reactor.Carbonized briquettes and furnished blends exhibited inferior gasifcation performance compared to the carbonized pellets.In the absence of tar blockage problems,steady-state conditions were achieved when pre-treated feedstock was used.Under steady-state conditions for carbonized pellets gasifcation operated at an equivalence ratio of 0.32,cold gas efciency and carbon conversion achieved 49.2%and 70.5%,respectively.Overall efciency and maximum power output of 20.3%and 21 kW were realised,respectively.It was found that the system could keep stable while the low heating valve of syngas was over 4 MJ/m^(3)on condition that avoiding tar blocking issues.The results indicate that the proposed compact ultra-small power generation system is a technically feasible approach to remedy power shortage challenge.In addition,process simulation considering carbonized wood gasifcation combined power generation was formulated to produce syngas and electricity.Woody pellets with the fow rate of 20 kg/h could generate a 15.18 kW power at the air fow rate of 40 Nm^(3)/h,which is in a good agreement with 15 kW in the 100 h operation.It is indicated that the gasifcation combined power generation cycle simulated by Aspen simulator could achieve reliable data to assist the complicated experiment operation.展开更多
文摘To investigate the overall performance of reverse energy bypass scramjet,firstly a variable spe⁃cific heat method combined with a chemical balance calculation module for combustion products were used to es⁃tablish a benchmark scramjet performance evaluation model.Based on the test data of typical flying point of Mach 7 with the altitude of 29 km,the reliability of the model was verified.The deviations of parameters such as the to⁃tal pressure loss of combustor between the model and the test data were analyzed.Furtherly,an analytical method for post-combustion magnetohydrodynamic power generation was established;by embedding the above method into the overall performance evaluation model,performance prediction considering the power generation effect was realized.Finally,based on the above model,variety regulations of the inlet and the outlet parameters of the power generation channel and performance parameters including the engine specific impulse and the unit thrust under different enthalpy extraction ratios and load factors were analyzed.It could be concluded that the model can reliably predict the variations of key parameters.As the value of the load factor increases,the value of the conduc⁃tivity required to reach the specified enthalpy extraction ratio first decreases and then increases,which is approxi⁃mately parabolic.In order to reduce the demand for the gas conductivity for MHD power generation,the load fac⁃tor should be around 0.5.When the load factor is 0.4 and the magnetic induction intensity is 2.5 T,if the enthalpy extraction ratio reaches 0.5%,the engine specific impulse performance reduces about 3.58%.
文摘This study explores off-grid power generation business models in the Lao People's Democratic Republic(Lao PDR),with the objective of identifying viable pathways to expand energy access in rural and underserved regions.The research aims to analyze and evaluate various business models in terms of their technical,economic,and social viability within the unique geographic and policy context of Lao PDR.There are two level of the research objectives:High Level Objectives(HLO)and Concreted Research Objectives(CRO).For HLO is that an appropriated off-grid power generation business model for Laos supports the Lao PDR Government’s commitment to promote an inclusive green growth development agenda that ensures lowered GHG emissions and increased energy efficiency.The Lao PDR National Determined Contribution(NDC)to the United Nations Framework Convention on Climate Change(UNFCCC)notes the country’s ambitious plans to lower energy consumption and reduce GHG emissions.While the CRO are focused on learning strategies,regulation and practical lessons from other countries the ASEAN region on the off-grid development and business model.To analyze and investigate the environmental strategy of business model under external and internal context and related and considered factors.And finally,this is to conclude and recommend the off-grid power generation business model as the research conclusion,which will become a support mechanism for the companies to operate consistently over many years into the future according to ambitious goal for supplying modern and save energy for rural families by 2030.
文摘In the original publication,mistakenly first and corresponding affiliation is given as:Thermoelectricity Technology Center,Hangzhou Dahe Thermo-Magnetics Co.Ltd,Hangzhou 310053,ChinaThe correct first and corresponding affiliation is:State Key Laboratory of Silicon Materials,School of Materials Science and Engineering,Zhejiang University,Hangzhou 310027,China.
文摘In this study,the power generation difference between the east-west and the north-south orientation of the vertically installed heterojunction solar cell(HJT)modules was deeply discussed.East-west oriented HJT module has 30%higher power generation,especially in desert photovoltaic(PV)with a bimodal distribution.While the south-north one has a single peak,the same as normal PV modules.Vertical power generation technology of HJT also has less land occupation,which is of great significance for optimizing the design of photovoltaic systems.
基金support from the National Natural Science Foundation of China[Grant No.71874121,No.71671121 and No.71431005]the support from the National Key R&D Programme of China[Grant No.2018YFC0704400]+1 种基金the support from Major Projects of the National Social Science Fund of China[Grant No.17ZDA065]the support from the General Project of the Humanities and Social Science Fund of the Chinese Ministry of Education[Grant No.21YJA630023].
文摘With the proposed carbon-neutrality targets,intermittent renewable energy will become increasingly significant for the power sector in the future.It is vital to study its development paths,particularly for wind power and photovoltaics,while considering constraints on diffusion potential.Using learning curves,dynamic programming,and Bass models,this study analyzes technological diffusion trends to determine the most cost-effective development route for intermittent renewable energy power generation in China by 2060.This study simplifies reality by examining the individual diffusion processes of wind and photovoltaic power,focusing on the self-diffusion characteristics of the two technologies.The study assumes that self-diffusion is the primary driver of future development and describe the influence of multiple factors.The study finds that supportive policies are key drivers of development in the early stages of intermittent renewable energy deployment,especially for photovoltaics.The current diffusion scale of photovoltaics has a greater positive impact on its future development than that of wind power due to lower costs.In the long term,the phased goal for 2030 is projected to be met ahead of schedule,and the majority of future intermittent renewable energy output is expected to come from photovoltaics.The rapid development phases of photovoltaic and wind power conclude at similar times,but the maximum diffusion potential of photovoltaics is higher than that of wind power.Investment constraints and technological levels affect the initial and middle phases of the development path,but their effects are limited.The capacity of the power grid remains the key constraint in the entire research field.
文摘With the continuous adjustment of the energy structure,photovoltaic(PV)power generation projects are increasing,playing a crucial role in promoting the application of clean energy.However,the current audit of completed final accounts for photovoltaic power generation projects faces many challenges,such as incomplete institutional processes,scattered archive management materials,inadequate digital intelligence systems,and insufficient analysis of final account amounts.Based on this,this article aims to deeply analyze these issues and propose targeted audit suggestions to standardize the construction and audit work of photovoltaic power generation projects and promote the sustainable and healthy development of the photovoltaic power generation business.
基金supported by the 2022 Sanya Science and Technology Innovation Project,China(No.2022KJCX03)the Sanya Science and Education Innovation Park,Wuhan University of Technology,China(Grant No.2022KF0028)the Hainan Provincial Joint Project of Sanya Yazhou Bay Science and Technology City,China(Grant No.2021JJLH0036).
文摘This study investigates the Maximum Power Point Tracking(MPPT)control method of offshore windphotovoltaic hybrid power generation system with offshore crane-assisted.A new algorithm of Global Fast Integral Sliding Mode Control(GFISMC)is proposed based on the tip speed ratio method and sliding mode control.The algorithm uses fast integral sliding mode surface and fuzzy fast switching control items to ensure that the offshore wind power generation system can track the maximum power point quickly and with low jitter.An offshore wind power generation system model is presented to verify the algorithm effect.An offshore off-grid wind-solar hybrid power generation systemis built in MATLAB/Simulink.Compared with other MPPT algorithms,this study has specific quantitative improvements in terms of convergence speed,tracking accuracy or computational efficiency.Finally,the improved algorithm is further analyzed and carried out by using Yuankuan Energy’s ModelingTech semi-physical simulation platform.The results verify the feasibility and effectiveness of the improved algorithm in the offshore wind-solar hybrid power generation system.
文摘This paper develops a high time-resolution optimal power generation mix model in its time resolution of 10 minutes on 365 days by linear programming technique. The model allows us to analyse the massive deployment of photovoltaic system and wind power generation in power system explicitly considering those short-term output variation. PV （photovoltaic） and wind output are estimated, employing meteorological database. Simulation results reveal that variable fluctuation derived from a high penetration level of those renewables is controlled by quick load following operation of natural gas combined cycle power plant, pumped-storage hydro power, stationary NAS （sodium and sulfur） battery and the output suppression control of PV and wind. It additionally turns out that the operational configuration of those technologies for the renewable variability differs significantly depending on those renewable output variations in each season and solving the seasonal electricity imbalance as well as the daily imbalance is important if variable renewables are massively deployed.
文摘On the basis of introducing clean power generation technologies, the author calculated and analyzed the investment, economy and environmental protection of these technologies, posed his views of giving the priorities to the development of supercritical and ultra-supercritical pressure coal-fired power generation technologies and taking vigorous action to nuclear power generation technology within the following 5-10 years, exploiting wind power within the following 10-15 years, and suggested that the installed capacity of nuclear power reach 80-100 GW and that of wind power reach 50-80 GW by 2020.
文摘This paper discusses the potential and prospect of building-integrated photovoltaics (BIPV) for solar electrical power generation in China.The BIPV technology has been identified as the most economical renewable energy resource to contribute to world electrical energy demand for protecting environment from reduced fossil fuel consumption.The available solar energy resource of 14 cities and the potential power generation from PV claddings in buildings in China were estimated.The economical analysis of BIPV application is discussed.It is found that the potential is significant and the government should play an important role in its development.
文摘Through a great many qualitative and quantitative analyses, this paperstudies the development of gas power in China in the coming ten years based oninvestigations of more than one year. Some good advices are suggested toinvestors and decision-makers, such as the advantages and disadvantages ofpower generation using natural gas, development plans of local power grids, andproblems necessary to be noted and solved.[
文摘This paper presents a new power generation structure that can provide DC energy for passive UHF RFID with high sensitivity and high efficiency. The structure is designed with 0.18μm standard CMOS technology, including two charge pumps,a current reference, and a group of bias circuits. Low-voltage performance is improved thanks to the bias structure,which eliminates the threshold voltage drop and body-effect of conventional circuits. A 350mV minimum input level is required to generate a 1.5V power supply for a 100k~ load with power conversion efficiency （PCE） of 22%. PCE up to 29.8% is achieved with a 60kΩ load. Simulation results show that the new circuit is superior to conventional charge pumps.
文摘No matter from the economic perspective, or from the social perspective, to gradually achieve sustainable development, will need to attach importance to the construction of the energy system, give priority to the use of renewable energy, but gradually increase in population, people's life gradually improve environment, represented by oil nonrenewable resources have been in a state of being long-term overexploitation. In order to meet the later development demand for energy, it is necessary to pay attention to the application of renewable energy, and solar energy is a kind of clean, environmental and renewable energy, so people gradually pay attention to the application of solar energy. Solar energy can be applied in many fields, such as the popular solar oven in the past, but now through solar photovoltaic power generation becomes the application trend of renewable energy in the future. This paper analyzes the application status of solar photovoltaic power generation technology, and describes the future development trend for reference.
基金supported by the National Natural Science Foundation of China(No.21878176)National Key Research and Development Program of China(No.2018YFA0902200)financially supported by the Imperial College President’s PhD Scholarship Scheme。
文摘Lignocellulosic biomass has attracted great interest in recent years for energy production due to its renewability and carbon-neutral nature.There are various ways to convert lignocellulose to gaseous,liquid and solid fuels via thermochemical,chemical or biological approaches.Typical biomass derived fuels include syngas,bio-gas,bio-oil,bioethanol and biochar,all of which could be used as fuels for furnace,engine,turbine or fuel cells.Direct biomass fuel cells mediated by various electron carriers provide a new direction of lignocellulose conversion.Various metal and non-metal based carriers have been screened for mediating the electron transfer from biomass to oxygen thus generating electricity.The power density of direct biomass fuel cells can be over 100 mW cm^(-2),which shows promise for practical applications.Lignocellulose and its isolated components,primarily cellulose and lignin,have also been paid considerable attention as sustainable carbonaceous materials for preparation of electrodes for supercapacitors,lithium-ion batteries and lithium-sulfur batteries.In this paper,we have provided a state-of-the-art review on the research progress of lignocellulosic biomass as feedstock and materials for power generation and energy storage focusing on the chemistry aspects of the processes.It was recommended that process integration should be performed to reduce the cost for thermochemical and biological conversion of lignocellulose to biofuels,while efforts should be made to increase efficiency and improve the properties for biomass fuelled fuel cells and biomass derived electrodes for energy storage.
基金National Natural Science Foundation of China （10972236） The Scientific and Technical Innovation for Postgraduates of Air Force Engineering University （DX2010102）
文摘This paper presents a preliminary experimental investigation on magnetohydrodynamic （MHD） power generation using seeded supersonic argon flow as working fluid. Helium and argon are used as driver and driven gas respectively in a shock tunnel. Equilibrium contact surface operating mode is used to obtain high temperature gas, and the conductivity is obtained by adding seed K2CO3 powder into the driven section. Under the conditions of nozzle inlet total pressure being 0.32 MPa, total temperature 6 504 K, magnetic field density about 0.5 T and nozzle outlet velocity 1 959 m/s, induction voltage and short-circuit current of the segmentation MHD power generation channel are measured, and the experimental results agree with theoretical calculations; the average conductivity is about 20 S/m calculated from characteristics of voltage and current. When load factor is 0.5, the maximum power density of the MHD power generation channel reaches 4.797 1 MW/m3, and the maximum enthalpy extraction rate is 0.34%. Finally, the principle and method of indirect testing for gas state parameters are derived and analyzed.
基金funded by the“Hot Dry Rock Resources Exploration and Production Demonstration Project”of the China Geological Survey(DD20190131,DD20190135,DD20211336).
文摘Hot dry rock(HDR)is a kind of clean energy with significant potential.Since the 1970s,the United States,Japan,France,Australia,and other countries have attempted to conduct several HDR development research projects to extract thermal energy by breaking through key technologies.However,up to now,the development of HDR is still in the research,development,and demonstration stage.An HDR exploration borehole(with 236℃ at a depth of 3705 m)was drilled into Triassic granite in the Gonghe Basin in northwest China in 2017.Subsequently,China Geological Survey(CGS)launched the HDR resources exploration and production demonstration project in 2019.After three years of efforts,a sequence of significant technological breakthroughs have been made,including the genetic model of deep heat sources,directional drilling and well completion in high-temperature hard rock,large-scale reservoir stimulation,reservoir characterization,and productivity evaluation,reservoir connectivity and flow circulation,efficient thermoelectric conversion,monitoring,and geological risk assessment,etc.Then the whole-process technological system for HDR exploration and production has been preliminarily established accordingly.The first power generation test was completed in November 2021.The results of this project will provide scientific support for HDR development and utilization in the future.
文摘Due to growing concerns regarding climate change and environmental protection,smart power generation has become essential for the economical and safe operation of both conventional thermal power plants and sustainable energy.Traditional first-principle model-based methods are becoming insufficient when faced with the ever-growing system scale and its various uncertainties.The burgeoning era of machine learning(ML)and data-driven control(DDC)techniques promises an improved alternative to these outdated methods.This paper reviews typical applications of ML and DDC at the level of monitoring,control,optimization,and fault detection of power generation systems,with a particular focus on uncovering how these methods can function in evaluating,counteracting,or withstanding the effects of the associated uncertainties.A holistic view is provided on the control techniques of smart power generation,from the regulation level to the planning level.The benefits of ML and DDC techniques are accordingly interpreted in terms of visibility,maneuverability,flexibility,profitability,and safety(abbreviated as the“5-TYs”),respectively.Finally,an outlook on future research and applications is presented.
基金co-supported by the National Natural Science Foundation of China (No. 11372352)the Shaanxi Province Science Foundation of China (No. 2013JQ1016)
文摘Magnetohydrodynamic (MHD) power generation with supersonic non-equilibrium plasma is demonstrated. Capacitively coupled radio frequency (RF) discharge (6 MHz, maximum continual power output of 200 W) was adopted to ionize the Mach number 3.5 (650 m/s), 0.023 kg/m(3) airflow. In a MHD channel of 16 mm x 10 mm x 20 mm, MHD open voltage of 10 V is realized in the magnetic field of 1.25 T, and power of 0.12 mW is extracted steadily and continuously in the magnetic field of 1 T. The reasons for limited power generation are proposed as: low conductivity of RF discharge; large touch resistance between MHD electrode and plasma; strong current eddies due to flow boundary layer. In addition, the cathode voltage fall is too low to have obvious effects on MHD power generation. (C) 2016 Chinese Society of Aeronautics and Astronautics. Production and hosting by Elsevier Ltd.
基金This work was supported of National Natural Science Foundation of China Fund(No.52306033)State Key Laboratory of Engines Fund(No.SKLE-K2022-07)the Jiangxi Provincial Postgraduate Innovation Special Fund(No.YC2022-s513).
文摘The supercritical CO_(2) Brayton cycle is considered a promising energy conversion system for Generation IV reactors for its simple layout,compact structure,and high cycle efficiency.Mathematical models of four Brayton cycle layouts are developed in this study for different reactors to reduce the cost and increase the thermohydraulic performance of nuclear power generation to promote the commercialization of nuclear energy.Parametric analysis,multi-objective optimizations,and four decision-making methods are applied to obtain each Brayton scheme’s optimal thermohydraulic and economic indexes.Results show that for the same design thermal power scale of reactors,the higher the core’s exit temperature,the better the Brayton cycle’s thermo-economic performance.Among the four-cycle layouts,the recompression cycle(RC)has the best overall performance,followed by the simple recuperation cycle(SR)and the intercooling cycle(IC),and the worst is the reheating cycle(RH).However,RH has the lowest total cost of investment(C_(tot))of$1619.85 million,and IC has the lowest levelized cost of energy(LCOE)of 0.012$/(kWh).The nuclear Brayton cycle system’s overall performance has been improved due to optimization.The performance of the molten salt reactor combined with the intercooling cycle(MSR-IC)scheme has the greatest improvement,with the net output power(W_(net)),thermal efficiencyη_(t),and exergy efficiency(η_(e))improved by 8.58%,8.58%,and 11.21%,respectively.The performance of the lead-cooled fast reactor combined with the simple recuperation cycle scheme was optimized to increase C_(tot) by 27.78%.In comparison,the internal rate of return(IRR)increased by only 7.8%,which is not friendly to investors with limited funds.For the nuclear Brayton cycle,the molten salt reactor combined with the recompression cycle scheme should receive priority,and the gas-cooled fast reactor combined with the reheating cycle scheme should be considered carefully.
基金The authors thank for the project of the National Key Research and development(R&D)Program and International Science and Technology Innovation Project between Governments(2021YFE0108900)Pujiang Talent Program Supported by Fund of Shanghai Science and Technology Committee(project code:20PJ1402800)supported by Innovative Science and Technology Initiative for Security(Ministry of Defence,Japan).
文摘Disaster-hit and/or un-electrifed remote areas usually have electricity accessibility issues and an abundance of plant-derived debris and wood from destroyed wooden structures;this can be potentially addressed by employing a decentralized ultrasmall biomass-fed gasifcation power generating system.This paper presents an assessment of the technical viability of an ultra-small gasifcation system that utilizes densifed carbonized wood pellets/briquettes.The setup was run continuously for 100 h.A variety of biomass was densifed and carbonized by harnessing fugitive heat sources before charging into the reactor.Carbonized briquettes and furnished blends exhibited inferior gasifcation performance compared to the carbonized pellets.In the absence of tar blockage problems,steady-state conditions were achieved when pre-treated feedstock was used.Under steady-state conditions for carbonized pellets gasifcation operated at an equivalence ratio of 0.32,cold gas efciency and carbon conversion achieved 49.2%and 70.5%,respectively.Overall efciency and maximum power output of 20.3%and 21 kW were realised,respectively.It was found that the system could keep stable while the low heating valve of syngas was over 4 MJ/m^(3)on condition that avoiding tar blocking issues.The results indicate that the proposed compact ultra-small power generation system is a technically feasible approach to remedy power shortage challenge.In addition,process simulation considering carbonized wood gasifcation combined power generation was formulated to produce syngas and electricity.Woody pellets with the fow rate of 20 kg/h could generate a 15.18 kW power at the air fow rate of 40 Nm^(3)/h,which is in a good agreement with 15 kW in the 100 h operation.It is indicated that the gasifcation combined power generation cycle simulated by Aspen simulator could achieve reliable data to assist the complicated experiment operation.
