Peak load and wind energy emission pressure rise more as wind energy penetration keeps growing,which affects the stabilization of the PS(power system).This paper suggests integrated optimal dispatching of thermal powe...Peak load and wind energy emission pressure rise more as wind energy penetration keeps growing,which affects the stabilization of the PS(power system).This paper suggests integrated optimal dispatching of thermal power generators and BESS(battery energy storage system)taking wind energy emission grading punishment and deep peak clipping into consideration.Firstly,in order to minimize wind abandonment,a hierarchical wind abandonment penalty strategy based on fuzzy control is designed and introduced,and the optimal grid-connected power of wind energy is determined as a result of minimizing the peak cutting cost of the system.Secondly,considering BESS and thermal power,the management approach of BESS-assisted virtual peak clipping of thermal power generators is aimed at reducing the degree of deep peak clipping of thermal power generators and optimizing the output of thermal power generators and the charging and discharging power of BESS.Finally,Give an example of how this strategy has been effective in reducing abandonment rates by 0.66% and 7.46% individually for different wind penetration programs,and the daily average can reduce the peak clipping power output of thermal power generators by 42.97 and 72.31 MWh and enhances the effect and economy of system peak clipping.展开更多
This study aims to evaluate the solar and wind energy potential across Razavi Khorasan Province,Iran,with a specific focus on the Khaf region.A preliminary assessment of mean solar radiation,mean wind speeds,and Weibu...This study aims to evaluate the solar and wind energy potential across Razavi Khorasan Province,Iran,with a specific focus on the Khaf region.A preliminary assessment of mean solar radiation,mean wind speeds,and Weibull distribution parameters was conducted for different towns and zones within the province.The findings showed that Khaf has favorable characteristics for further analysis.The solar and wind energy metrics examined include global horizontal irradiance,clearness index,wind rose patterns,and turbulence intensity.At a height of 40 m,Khaf’s wind power density reached 1650 W/m^(2),indicating exceptional wind energy generation potential.Additionally,Khaf received an average annual solar radiation of 2046 kW·h/m^(2),representing significant solar energy potential.Harnessing these substantial renewable resources in Khaf could allow Razavi Khorasan Province to reduce reliance on fossil fuels,improve energy sustainability,and mitigate climate change impacts.This research contributes an in-depth assessment of Razavi Khorasan's solar and wind energy potential,particularly for the promising Khaf region.Further work may examine optimal sites for renewable energy projects and grid integration strategies to leverage these resources.展开更多
The recognition on the trend of wind energy stability is still extremely rare,although it is closely related to acquisition efficiency,grid connection,equipment lifetime,and costs of wind energy utilization.Using the ...The recognition on the trend of wind energy stability is still extremely rare,although it is closely related to acquisition efficiency,grid connection,equipment lifetime,and costs of wind energy utilization.Using the 40-year(1979–2018)ERA-Interim data from the European Center for Medium-Range Weather Forecasts,this study presented the spatial-temporal distribution and climatic trend of the stability of global offshore wind energy as well as the abrupt phenomenon of wind energy stability in key regions over the past 40 years with the climatic analysis method and Mann-Kendall(M-K)test.The results show the following 5 points.(1)According to the coefficient of variation(C_(v))of the wind power density,there are six permanent stable zones of global offshore wind energy:the southeast and northeast trade wind zones in the Indian,Pacific and Atlantic oceans,the Southern Hemisphere westerly,and a semi-permanent stable zone(North Indian Ocean).(2)There are six lowvalue zones for both seasonal variability index(S_(v))and monthly variability index(M_(v))globally,with a similar spatial distribution as that of the six permanent stable zones.M_(v) and S_(v) in the Arabian Sea are the highest in the world.(3)After C_(v),M_(v) and S_(v) are comprehensively considered,the six permanent stable zones have an obvious advantage in the stability of wind energy over other sea areas,with C_(v) below 0.8,M_(v) within 1.0,and S_(v) within 0.7 all the year round.(4)The global stability of offshore wind energy shows a positive climatic trend for the past four decades.C_(v),M_(v) and S_(v) have not changed significantly or decreased in most of the global ocean during 1979 to2018.That is,wind energy is flat or more stable,while the monthly and seasonal variabilities tend to shrink/smooth,which is beneficial for wind energy utilization.(5)C_(v) in the low-latitude Pacific and M_(v) and S_(v) in both the North Indian Ocean and the low-latitude Pacific have an obvious abrupt phenomenon at the end of the20th century.展开更多
Renewable energy is becoming more attractive as traditional fossil fuels are rapidly depleted and expensive,and their use would release pollutants.Power systems that use both wind and solar energy are more reliable an...Renewable energy is becoming more attractive as traditional fossil fuels are rapidly depleted and expensive,and their use would release pollutants.Power systems that use both wind and solar energy are more reliable and efficient than those that utilize only one energy.Hybrid renewable energy systems(HRES)are viable for remote areas operating in standalone mode.This paper aims to present the state-of-the-art research on off-grid solar-wind hybrid energy systems over the last two decades.More than 1500 published articles extracted from the Web of Science are analyzed by bibliometric methods and processed by CiteSpace to present the results with figures and tables.Productive countries and highly cited authors are identified,and hot topics with hotspot articles are shown in landscape and timeline views.Emerging trends and new developments related to techno-economic analysis and microgrids,as well as the application of HOMER software,are predicted based on the analysis of citation bursts.Furthermore,the opportunities of hybrid energy systems for sustainable development are discussed,and challenges and possible solutions are proposed.The study of this paper provides researchers with a comprehensive understanding and intuitive representation of standalone solar-wind hybrid energy systems.展开更多
As part of the national strategy to further develop the wind energy sector,the eight prefectures of Upper Guinea have been selected.Using meteorological data recorded over thirty years(1991-2021)at a height of 20 m,we...As part of the national strategy to further develop the wind energy sector,the eight prefectures of Upper Guinea have been selected.Using meteorological data recorded over thirty years(1991-2021)at a height of 20 m,we assessed wind resources in terms of characteristic speeds,power and available energy.To this end,the Weibull distribution method was used and the following values were obtained:3.66 m/s for the average speed;1,102.83 W/m^(2)for the available power and 8,747.06 kWh/m^(2)/year for the annual available energy.展开更多
China wind atlas was made by numerical simulation and the wind energy potential in China was calculated. The model system for wind energy resource assessment was set up based on Canadian Wind Energy Simulating Toolkit...China wind atlas was made by numerical simulation and the wind energy potential in China was calculated. The model system for wind energy resource assessment was set up based on Canadian Wind Energy Simulating Toolkit (WEST) and the simulating method was as follows. First, the weather classes were obtained depend on meteorological data of 30 years. Then, driven by the initial meteorological field produced by each weather class, the meso-scale model ran for the distribution of wind energy resources according each weather class condition one by one. Finally, averaging all the modeling output weighted by the occurrence frequency of each weather class, the annual mean distribution of wind energy resources was worked out. Compared the simulated wind energy potential with other results from several activities and studies for wind energy resource assessment, it is found that the simulated wind energy potential in mainland of China is 3 times that from the second and the third investigations for wind energy resources by CMA, and is similar to the wind energy potential obtained by NREL in Solar and Wind Energy Resource Assessment(SWERA) project. The simulated offshore wind energy potential of China seems smaller than the true value. According to the simulated results of CMA and considering lots of limited factors to wind energy development, the final conclusion can be obtained that the wind energy availability in China is 700~1 200 GW, in which 600~1 000 GW is in mainland and 100~200 GW is on offshore, and wind power will become the important part of energy composition in future.展开更多
Wind energy is a kind of clean renewable energy, which is also relatively mature in technology, with largescale development conditions and prospect for the commercialization. The development of wind energy is a system...Wind energy is a kind of clean renewable energy, which is also relatively mature in technology, with largescale development conditions and prospect for the commercialization. The development of wind energy is a systematic project, involving policy, law, technology, economy, society, environment, education and other aspects. The relationship among all the aspects should be well treated and coordinated. This paper has discussed the following relationships which should be well coordinated: relationship between wind resources and wind energy development, relationship between the wind turbine generator system and the components, relationship between wind energy technology and wind energy industry, relationship between off-grid wind power and grid-connected wind power, relationship between wind farm and the power grid, relationship between onshore wind power and offshore wind power, relationship between wind energy and other energies, relationship between technology introduction and self-innovation, relationship among foreign-funded, joint ventured and domestic-funded enterprises and relationship between the government guidance and the market regulation, as well as giving out some suggestions.展开更多
The scientific development of wind energy based on local conditions is conducive to the urgent energy demand and environmental protection of Antarctic region.In this study,the ERA5 reanalysis data are used to evaluate...The scientific development of wind energy based on local conditions is conducive to the urgent energy demand and environmental protection of Antarctic region.In this study,the ERA5 reanalysis data are used to evaluate the wind energy resources in the Antarctic region.A series of key indicators,such as wind power density,effective wind speed occurrence,energy level occurrence and stability,are comprehensively considered by using climate statistical analysis methods to analyze the temporal and spatial distribution characteristics of Antarctic wind energy resources.The results show that the Antarctic region contains abundant wind energy resources,which benefits the construction of scientific research stations.The superior areas are the Southern Ocean and the coast of the East Antarctica,followed by the Transantarctic Mountains,the coast of the Bellingshausen Sea and Amundsen Sea.These areas have advantages in terms of wind power density(500-2500 W/m2),effective wind speed occurrence(80%-90%),energy level occur-rence(60%-90%)and stability(Cv:0.6-1,Mv:1.2-1.8,Sv:0.8-1.2).The Antarctic’s wind energy resources in wind power density,effective wind speed occurrence and energy level occurrence in autumn and winter are better than those in summer,while the coefficient of variation in summer is worse than that in autumn and winter.展开更多
Renewable energy has garnered attention due to the need for sustainable energy sources.Wind power has emerged as an alternative that has contributed to the transition towards cleaner energy.As the importance of wind e...Renewable energy has garnered attention due to the need for sustainable energy sources.Wind power has emerged as an alternative that has contributed to the transition towards cleaner energy.As the importance of wind energy grows,it can be crucial to provide forecasts that optimize its performance potential.Artificial intelligence(AI)methods have risen in prominence due to how well they can handle complicated systems while enhancing the accuracy of prediction.This study explored the area of AI to predict wind-energy production at a wind farm in Yalova,Turkey,using four different AI approaches:support vector machines(SVMs),decision trees,adaptive neuro-fuzzy inference systems(ANFIS)and artificial neural networks(ANNs).Wind speed and direction were considered as essential input parameters,with wind energy as the target parameter,and models are thoroughly evaluated using metrics such as the mean absolute percentage error(MAPE),coefficient of determination(R~2),and mean absolute error(MAE).The findings accentuate the superior performance of the SVM,which delivered the lowest MAPE(2.42%),the highest R~2(0.95),and the lowest MAE(71.21%)compared with actual values,while ANFIS was less effective in this context.The main aim of this comparative analysis was to rank the models to move to the next step in improving the least efficient methods by combining them with optimization algorithms,such as metaheuristic algorithms.展开更多
With the economic development, the problems of energy shortage become increasingly severe. As offshore wind energy has advantages, namely it is clean, renewable, not accounting for land area, without noise pollution, ...With the economic development, the problems of energy shortage become increasingly severe. As offshore wind energy has advantages, namely it is clean, renewable, not accounting for land area, without noise pollution, with large reserves, etc., which gradually attracts people's attention. In this paper, China's offshore annual average wind field and monthly average wind field under the mean climate state conditions are obtained, and the corresponding wind density distribution is calculated. China's offshore wind energy reserves and distribution conditions through the analysis of wind energy density distribution are summarized, and finally some suggestions for coastal offshore wind energy development and utilization in China are put forward.展开更多
In the paper,daily near-surface wind speed data from 462 stations are used to study the spatiotemporal characteristics of the annual and seasonal mean wind speed(MWS)and effective wind energy density(EWED)from 1960 to...In the paper,daily near-surface wind speed data from 462 stations are used to study the spatiotemporal characteristics of the annual and seasonal mean wind speed(MWS)and effective wind energy density(EWED)from 1960 to 2016,through the methods of kriging interpolation,leastsquares,correlation coefficient testing,and empirical orthogonal function(EOF)analysis.The results show that the annual MWS is larger than 3 m s-1 and the EWED is larger than 75 W m-2 in northern China and parts of coastal areas.However,the MWS and EWED values in southern China are all smaller than in northern China.Over the past 50 years,the annual and seasonal MWS in China has shown a significant decreasing trend,with the largest rate of decline in spring for northern China and winter for coastal areas.The annual MWS in some areas of Guangdong has an increasing trend,but it shows little change in southwestern China,South China,and west of Central China.Where the MWS is high,the rate of decline is also high.The main spatial distributions of the annual MWS and the annual EWED show high consistency,with a decreasing trend year by year.The decreasing trend of wind speed and wind energy resources in China is mainly related to global warming and land use/cover change.展开更多
[Objective] The aim was to explore the spatial and temporal distribution characteristics of wind energy resource and preservation in central and west area of Hexi Corridor. [Method] By dint of the wind speed data from...[Objective] The aim was to explore the spatial and temporal distribution characteristics of wind energy resource and preservation in central and west area of Hexi Corridor. [Method] By dint of the wind speed data from 1955 to 2007 in ten meteorological observation station in central and west area of Hexi Corridor,and special wind tower fine data from January to December in 2007,the distribution and reserves of the region's wind energy resources were studied. [Result] The results showed that environmental wind speed was relatively stable in central and west Hexi Corridor. There were no distinct changes in climate characteristics distribution. There were regional differences in the distribution of wind energy,and there was a large numerical area of wind energy in Gazhou County and Yumen City; Wind energy in the region generally was higher. The wind energy density was above 100 w/m2 in the 10 m layer,around 140 w/m2 in most places,and was more than 200 w/m2 in the large number area. The wind grew in vertical direction along with the linear growth of height. Each 10 m high wind increased to 15 w/m2 averagely,50m layer wind energy was greater than the general 240 w/m2 and there were obvious changes on daily and annual with wind energy in central and west area of Hexi Corridor. The duration from March to May was a wind energy-intensive stage,10m height from the ground in the wind around 10:00 in low-value. After growing from 11:00,it met the day largest number at 18:00,and then reduced gradually. Effective wind speed hours in the region in general were more than 6 200 h,and the value in the large areas was close to 7 600 h. [Conclusion] The study laid basis for the development and application of wind energy in central and west area of Hexi Corridor.展开更多
A method was introduced to assess the sustainability of energy production over the lifetime (~20 y) of wind turbines. Community Earth System Model simulations were downscaled for the tourist seasons (mid-May to mid-Se...A method was introduced to assess the sustainability of energy production over the lifetime (~20 y) of wind turbines. Community Earth System Model simulations were downscaled for the tourist seasons (mid-May to mid-September) of 2006 to 2012 (CESM-P1) and 2026 to 2032 (CESM-P2) to obtain a reference and projected wind-speed climatology, respectively. The wind speeds served to calculate the potential power output and capacity factors of seven turbine types. CESM-P1 wind-speed climatology, power output, and capacity factors were compared to those derived from wind speeds obtained by numerical weather forecasts for reference to known standard to wind-farm managers. Juneau, Alaska served as a virtual testbed as this region is known to experience changes in wind speeds in response to the Pacific Decadal Oscillation. CESM-P2 suggested about 2% decrease for wind speeds between the speeds at cut-in and rated power, and about 8% - 10% decrease in potential wind-power output. This means that in regions of decadal climate variations, the sustainability of wind-energy production should be part of the decision-making process. The study demonstrated that using mean values of wind-speeds can provide qualitative knowledge about decreases/increases in potential energy production, but not about the magnitude. Using the total individual wind-speed data of all seasons provided the same amount of total power output than summing up the power outputs of individual seasons. The main advantage of calculating individual seasonal wind-power outputs, however, is that it theoretically permits assessment of interannual variability in power output and capacity factors. Comparison to a known standard may help stakeholders in understanding of uncertainty and interpretation of projected changes.展开更多
The exploitation of wind energy is rapidly evolving and is manifested in the ever-expanding global network of offshore wind energy farms.For the Small Island Developing States of the Caribbean Sea(CS),harnessing this ...The exploitation of wind energy is rapidly evolving and is manifested in the ever-expanding global network of offshore wind energy farms.For the Small Island Developing States of the Caribbean Sea(CS),harnessing this mature technology is an important first step in the transition away from fossil fuels.This paper uses buoy and satellite observations of surface wind speed in the CS to estimate wind energy resources over the 2009–201911-year period and initiates hour-ahead forecasting using the long short-term memory(LSTM)network.Observations of wind power density(WPD)at the 100-m height showed a mean of approximately 1000 W/m^(2) in the Colombia Basin,though this value decreases radially to 600–800 W/m^(2) in the central CS to a minimum of approximately 250 W/m^(2) at its borders in the Venezuela Basin.The Caribbean Low-Level Jet(CLLJ)is also responsible for the waxing and waning of surface wind speed and as such,resource stability,though stable as estimated through monthly and seasonal coefficients of variation,is naturally governed by CLLJ activity.Using a commercially available offshore wind turbine,wind energy generation at four locations in the CS is estimated.Electricity production is greatest and most stable in the central CS than at either its eastern or western borders.Wind speed forecasts are also found to be more accurate at this location,and though technology currently restricts offshore wind turbines to shallow water,outward migration to and colonization of deeper water is an attractive option for energy exploitation.展开更多
With high resolution (1 kin), the distribution of wind energy resources in Hainan province and over its offshore waters is numerically simulated by using the Wind Energy Simulation Toolkit (WEST) model developed b...With high resolution (1 kin), the distribution of wind energy resources in Hainan province and over its offshore waters is numerically simulated by using the Wind Energy Simulation Toolkit (WEST) model developed by Meteorological Research Branch of Environment Canada. Compared with observations from eight coastal anemometric towers and 18 existing stations in the province, the simulations show good reproduction of the real distribution of wind resources in Hainan and over its offshore waters, with the relative error of annual mean wind speed being no more than 9% at the 70-m level. Moreover, based on the simulated results of WEST grids that are closest to where the eight wind towers are located, the annual mean wind speeds are further estimated by using the Danish software Wasp (Wind Atlas Analysis and Application Program). The estimated results are then compared with the observations from the towers. It shows that the relative error is also less than 9%. Therefore, WEST and WEST+WAsP will be useful tools for the assessment of wind energy resources in high resolution and selection of wind farm sites in Hainan province and over its offshore waters.展开更多
Wind energy development receives broad support but is often opposed at the local level due to nuisance concerns and uncertainties about how it affects the landowners living due to the turbines and the broader communit...Wind energy development receives broad support but is often opposed at the local level due to nuisance concerns and uncertainties about how it affects the landowners living due to the turbines and the broader community.Lo-cal opposition to wind energy development can be a powerful force slowing or even ending its implementation in a given region.Oklahoma,USA is currently ranked as 4^(th)in the United States in current wind energy production and has seen significant pushback from some local communities as a renewable energy resource.Previous studies have examined wind energy development’s impact on rural education income,and property values of different communities in Oklahoma.However,funding information on how wind energy development affects the individu-als living alongside the turbines are limited.Using fifteen interviews with landowners,site-managers,community representatives,and pro-wind non-profit organization representatives,this study finds that individuals who live in proximity to wind energy development,particularly those involved in the agricultural industry,have created novel and unique uses for wind farm infrastructure.It also finds that local perceptions of wind energy production are mostly positive and provides increased knowledge of how wind energy development affects the individuals and communities that are hosting the turbines and related infrastructure.展开更多
Wind energy is one of the most promising and renewable energy sources;however,owing to the limitations of device structures,collecting low-speed wind energy by triboelectric nanogenerators(TENGs)is still a huge challe...Wind energy is one of the most promising and renewable energy sources;however,owing to the limitations of device structures,collecting low-speed wind energy by triboelectric nanogenerators(TENGs)is still a huge challenge.To solve this problem,an ultra-durable and highly efficient windmill-like hybrid nanogenerator(W-HNG)is developed.Herein,the W-HNG composes coupled TENG and electromagnetic generator(EMG)and adopts a rotational contact-separation mode.This unique design efficiently avoids the wear of friction materials and ensures a prolonged service life.Moreover,the generator group is separated from the wind-driven part,which successfully prevents rotation resistance induced by the friction between rotor and stator in the conventional structures,and realizes low-speed wind energy harvesting.Additionally,the output characteristics of TENG can be complementary to the different performance advantages of EMG to achieve a satisfactory power production.The device is successfully driven when the wind speed is 1.8 m s−1,and the output power of TENG and EMG can achieve 0.95 and 3.7 mW,respectively.After power management,the W-HNG has been successfully applied as a power source for electronic devices.This work provides a simple,reliable,and durable device for improved performance toward large-scale low-speed breeze energy harvesting.展开更多
Greenhouse gas emissions are the main cause of today's climate change. To address this problem, the world is in an era of new round energy transformation, and the existing energy structure is being reformed. In th...Greenhouse gas emissions are the main cause of today's climate change. To address this problem, the world is in an era of new round energy transformation, and the existing energy structure is being reformed. In this paper, according to the Chinese government's action plan for coping with climate change, the China's wind energy sustainable development goals and development route are discussed, and the countermeasures and suggestions are put forward. Wind energy is currently a kind of important renewable energy with matured technology which can be scale-up developed and put into commercial application, and in this transformation, wind energy will play a key role with other non-fossil energy sources. The development and utilization of wind energy is a systematic project, which needs to be solved from the aspects of policy, technology and management. At present, China is in the stage of transferring from "large wind power country" to "strong wind power country", opportunities and challenges coexist, and the advantages of China's socialist system could be fully used, which can concentrate power to do big things and make contribution in the process of realizing global energy transformation.展开更多
Based on the analysis of ocean dynamic condition and sediment environment, conclusions can be drawn that strong wind is an essential factor influencing sudden sedimentation in outer channel. Through theoretical analys...Based on the analysis of ocean dynamic condition and sediment environment, conclusions can be drawn that strong wind is an essential factor influencing sudden sedimentation in outer channel. Through theoretical analysis, it changes the complex process that wind raises wave, wave tilts sediment and current transports sediment into a comprehensive factor, and obtains mathematical formula between effective wind energy and the thickness of sudden sedimentation. The parametees in this formula are determined with field data of Huanghua Port. It may be used to predict siltation thickness and volume along the channel. By analyzing and comparing the difference in ocean hydrodynamic conditions and seabed material between Huanghua Port and Binzhou Port, the proposed formula can be used to predict sudden sedimentation in Binzhou Port and the calculated results is rehable. By predicting it on different combination plans among different recurrence in- tervals, entrance locations and channel classes, it provides references for the plane design of Binzhou Port.展开更多
Following the current rapid development of the Internet of Things(IoT)and wireless condition monitoring systems,energy harvesters which use ambient energy have become a key part of achieving an energy-autonomous syste...Following the current rapid development of the Internet of Things(IoT)and wireless condition monitoring systems,energy harvesters which use ambient energy have become a key part of achieving an energy-autonomous system.Miniature wind energy harvesters have attracted widespread attention because of their great potential of power density as well as the rich availability of wind energy in many possible areas of application.This article provides readers with a glimpse into the state-of-the-art of miniature wind energy harvesters.The crucial factors for them to achieve high working efficiency under lower operational wind speed excitation are analyzed.Various potential energy coupling mechanisms are discussed in detail.Design approaches for broadening operational wind-speed-range given a variety of energy coupling mechanisms are also presented,as observed in the literature.Performance enhancement mechanisms including hydrodynamic configuration optimization,and non-linear vibration pick-up structure are reviewed.Conclusions are drawn and the outlook for each coupling mechanisms is presented.展开更多
基金supported by Jilin Province Higher Education Teaching Reform Research Project in 2021(JLJY202186163419).
文摘Peak load and wind energy emission pressure rise more as wind energy penetration keeps growing,which affects the stabilization of the PS(power system).This paper suggests integrated optimal dispatching of thermal power generators and BESS(battery energy storage system)taking wind energy emission grading punishment and deep peak clipping into consideration.Firstly,in order to minimize wind abandonment,a hierarchical wind abandonment penalty strategy based on fuzzy control is designed and introduced,and the optimal grid-connected power of wind energy is determined as a result of minimizing the peak cutting cost of the system.Secondly,considering BESS and thermal power,the management approach of BESS-assisted virtual peak clipping of thermal power generators is aimed at reducing the degree of deep peak clipping of thermal power generators and optimizing the output of thermal power generators and the charging and discharging power of BESS.Finally,Give an example of how this strategy has been effective in reducing abandonment rates by 0.66% and 7.46% individually for different wind penetration programs,and the daily average can reduce the peak clipping power output of thermal power generators by 42.97 and 72.31 MWh and enhances the effect and economy of system peak clipping.
文摘This study aims to evaluate the solar and wind energy potential across Razavi Khorasan Province,Iran,with a specific focus on the Khaf region.A preliminary assessment of mean solar radiation,mean wind speeds,and Weibull distribution parameters was conducted for different towns and zones within the province.The findings showed that Khaf has favorable characteristics for further analysis.The solar and wind energy metrics examined include global horizontal irradiance,clearness index,wind rose patterns,and turbulence intensity.At a height of 40 m,Khaf’s wind power density reached 1650 W/m^(2),indicating exceptional wind energy generation potential.Additionally,Khaf received an average annual solar radiation of 2046 kW·h/m^(2),representing significant solar energy potential.Harnessing these substantial renewable resources in Khaf could allow Razavi Khorasan Province to reduce reliance on fossil fuels,improve energy sustainability,and mitigate climate change impacts.This research contributes an in-depth assessment of Razavi Khorasan's solar and wind energy potential,particularly for the promising Khaf region.Further work may examine optimal sites for renewable energy projects and grid integration strategies to leverage these resources.
基金The Open Fund Project of Shandong Provincial Key Laboratory of Ocean EngineeringOcean University of China under contract No.kloe201901the Open Research Fund of State Key Laboratory of Estuarine and Coastal Research under contract No.SKLEC-KF201707。
文摘The recognition on the trend of wind energy stability is still extremely rare,although it is closely related to acquisition efficiency,grid connection,equipment lifetime,and costs of wind energy utilization.Using the 40-year(1979–2018)ERA-Interim data from the European Center for Medium-Range Weather Forecasts,this study presented the spatial-temporal distribution and climatic trend of the stability of global offshore wind energy as well as the abrupt phenomenon of wind energy stability in key regions over the past 40 years with the climatic analysis method and Mann-Kendall(M-K)test.The results show the following 5 points.(1)According to the coefficient of variation(C_(v))of the wind power density,there are six permanent stable zones of global offshore wind energy:the southeast and northeast trade wind zones in the Indian,Pacific and Atlantic oceans,the Southern Hemisphere westerly,and a semi-permanent stable zone(North Indian Ocean).(2)There are six lowvalue zones for both seasonal variability index(S_(v))and monthly variability index(M_(v))globally,with a similar spatial distribution as that of the six permanent stable zones.M_(v) and S_(v) in the Arabian Sea are the highest in the world.(3)After C_(v),M_(v) and S_(v) are comprehensively considered,the six permanent stable zones have an obvious advantage in the stability of wind energy over other sea areas,with C_(v) below 0.8,M_(v) within 1.0,and S_(v) within 0.7 all the year round.(4)The global stability of offshore wind energy shows a positive climatic trend for the past four decades.C_(v),M_(v) and S_(v) have not changed significantly or decreased in most of the global ocean during 1979 to2018.That is,wind energy is flat or more stable,while the monthly and seasonal variabilities tend to shrink/smooth,which is beneficial for wind energy utilization.(5)C_(v) in the low-latitude Pacific and M_(v) and S_(v) in both the North Indian Ocean and the low-latitude Pacific have an obvious abrupt phenomenon at the end of the20th century.
基金This work was supported by Education Department of Hunan Province,China under Grant 22C013(Q.Zhou received this grant and the sponsor’s websites is https://jyt.hunan.gov.cn/).
文摘Renewable energy is becoming more attractive as traditional fossil fuels are rapidly depleted and expensive,and their use would release pollutants.Power systems that use both wind and solar energy are more reliable and efficient than those that utilize only one energy.Hybrid renewable energy systems(HRES)are viable for remote areas operating in standalone mode.This paper aims to present the state-of-the-art research on off-grid solar-wind hybrid energy systems over the last two decades.More than 1500 published articles extracted from the Web of Science are analyzed by bibliometric methods and processed by CiteSpace to present the results with figures and tables.Productive countries and highly cited authors are identified,and hot topics with hotspot articles are shown in landscape and timeline views.Emerging trends and new developments related to techno-economic analysis and microgrids,as well as the application of HOMER software,are predicted based on the analysis of citation bursts.Furthermore,the opportunities of hybrid energy systems for sustainable development are discussed,and challenges and possible solutions are proposed.The study of this paper provides researchers with a comprehensive understanding and intuitive representation of standalone solar-wind hybrid energy systems.
文摘As part of the national strategy to further develop the wind energy sector,the eight prefectures of Upper Guinea have been selected.Using meteorological data recorded over thirty years(1991-2021)at a height of 20 m,we assessed wind resources in terms of characteristic speeds,power and available energy.To this end,the Weibull distribution method was used and the following values were obtained:3.66 m/s for the average speed;1,102.83 W/m^(2)for the available power and 8,747.06 kWh/m^(2)/year for the annual available energy.
文摘China wind atlas was made by numerical simulation and the wind energy potential in China was calculated. The model system for wind energy resource assessment was set up based on Canadian Wind Energy Simulating Toolkit (WEST) and the simulating method was as follows. First, the weather classes were obtained depend on meteorological data of 30 years. Then, driven by the initial meteorological field produced by each weather class, the meso-scale model ran for the distribution of wind energy resources according each weather class condition one by one. Finally, averaging all the modeling output weighted by the occurrence frequency of each weather class, the annual mean distribution of wind energy resources was worked out. Compared the simulated wind energy potential with other results from several activities and studies for wind energy resource assessment, it is found that the simulated wind energy potential in mainland of China is 3 times that from the second and the third investigations for wind energy resources by CMA, and is similar to the wind energy potential obtained by NREL in Solar and Wind Energy Resource Assessment(SWERA) project. The simulated offshore wind energy potential of China seems smaller than the true value. According to the simulated results of CMA and considering lots of limited factors to wind energy development, the final conclusion can be obtained that the wind energy availability in China is 700~1 200 GW, in which 600~1 000 GW is in mainland and 100~200 GW is on offshore, and wind power will become the important part of energy composition in future.
文摘Wind energy is a kind of clean renewable energy, which is also relatively mature in technology, with largescale development conditions and prospect for the commercialization. The development of wind energy is a systematic project, involving policy, law, technology, economy, society, environment, education and other aspects. The relationship among all the aspects should be well treated and coordinated. This paper has discussed the following relationships which should be well coordinated: relationship between wind resources and wind energy development, relationship between the wind turbine generator system and the components, relationship between wind energy technology and wind energy industry, relationship between off-grid wind power and grid-connected wind power, relationship between wind farm and the power grid, relationship between onshore wind power and offshore wind power, relationship between wind energy and other energies, relationship between technology introduction and self-innovation, relationship among foreign-funded, joint ventured and domestic-funded enterprises and relationship between the government guidance and the market regulation, as well as giving out some suggestions.
基金financially supported by the project of “Doctoralization of Master’s Program” of Marine Resources and Environment Research Group on the Maritime Silk Roadthe open fund project of Shandong Provincial Key Laboratory of Ocean Engineering,Ocean University of China (No. kloe201901)
文摘The scientific development of wind energy based on local conditions is conducive to the urgent energy demand and environmental protection of Antarctic region.In this study,the ERA5 reanalysis data are used to evaluate the wind energy resources in the Antarctic region.A series of key indicators,such as wind power density,effective wind speed occurrence,energy level occurrence and stability,are comprehensively considered by using climate statistical analysis methods to analyze the temporal and spatial distribution characteristics of Antarctic wind energy resources.The results show that the Antarctic region contains abundant wind energy resources,which benefits the construction of scientific research stations.The superior areas are the Southern Ocean and the coast of the East Antarctica,followed by the Transantarctic Mountains,the coast of the Bellingshausen Sea and Amundsen Sea.These areas have advantages in terms of wind power density(500-2500 W/m2),effective wind speed occurrence(80%-90%),energy level occur-rence(60%-90%)and stability(Cv:0.6-1,Mv:1.2-1.8,Sv:0.8-1.2).The Antarctic’s wind energy resources in wind power density,effective wind speed occurrence and energy level occurrence in autumn and winter are better than those in summer,while the coefficient of variation in summer is worse than that in autumn and winter.
文摘Renewable energy has garnered attention due to the need for sustainable energy sources.Wind power has emerged as an alternative that has contributed to the transition towards cleaner energy.As the importance of wind energy grows,it can be crucial to provide forecasts that optimize its performance potential.Artificial intelligence(AI)methods have risen in prominence due to how well they can handle complicated systems while enhancing the accuracy of prediction.This study explored the area of AI to predict wind-energy production at a wind farm in Yalova,Turkey,using four different AI approaches:support vector machines(SVMs),decision trees,adaptive neuro-fuzzy inference systems(ANFIS)and artificial neural networks(ANNs).Wind speed and direction were considered as essential input parameters,with wind energy as the target parameter,and models are thoroughly evaluated using metrics such as the mean absolute percentage error(MAPE),coefficient of determination(R~2),and mean absolute error(MAE).The findings accentuate the superior performance of the SVM,which delivered the lowest MAPE(2.42%),the highest R~2(0.95),and the lowest MAE(71.21%)compared with actual values,while ANFIS was less effective in this context.The main aim of this comparative analysis was to rank the models to move to the next step in improving the least efficient methods by combining them with optimization algorithms,such as metaheuristic algorithms.
文摘With the economic development, the problems of energy shortage become increasingly severe. As offshore wind energy has advantages, namely it is clean, renewable, not accounting for land area, without noise pollution, with large reserves, etc., which gradually attracts people's attention. In this paper, China's offshore annual average wind field and monthly average wind field under the mean climate state conditions are obtained, and the corresponding wind density distribution is calculated. China's offshore wind energy reserves and distribution conditions through the analysis of wind energy density distribution are summarized, and finally some suggestions for coastal offshore wind energy development and utilization in China are put forward.
基金This work was supported by the National Key R&D Program of China[grant numbers 2016YFA0600403 and 2016YFA0602501]the General Project of the National Natural Science Foundation of China[grant number 41875134].
文摘In the paper,daily near-surface wind speed data from 462 stations are used to study the spatiotemporal characteristics of the annual and seasonal mean wind speed(MWS)and effective wind energy density(EWED)from 1960 to 2016,through the methods of kriging interpolation,leastsquares,correlation coefficient testing,and empirical orthogonal function(EOF)analysis.The results show that the annual MWS is larger than 3 m s-1 and the EWED is larger than 75 W m-2 in northern China and parts of coastal areas.However,the MWS and EWED values in southern China are all smaller than in northern China.Over the past 50 years,the annual and seasonal MWS in China has shown a significant decreasing trend,with the largest rate of decline in spring for northern China and winter for coastal areas.The annual MWS in some areas of Guangdong has an increasing trend,but it shows little change in southwestern China,South China,and west of Central China.Where the MWS is high,the rate of decline is also high.The main spatial distributions of the annual MWS and the annual EWED show high consistency,with a decreasing trend year by year.The decreasing trend of wind speed and wind energy resources in China is mainly related to global warming and land use/cover change.
基金Supported by National Natural Science Fund (41075008)Chinese Meteorological Climate Changes Program (280200S011000)Gansu Meteorological Bureau Climate Science and Research Program(2011-09)~~
文摘[Objective] The aim was to explore the spatial and temporal distribution characteristics of wind energy resource and preservation in central and west area of Hexi Corridor. [Method] By dint of the wind speed data from 1955 to 2007 in ten meteorological observation station in central and west area of Hexi Corridor,and special wind tower fine data from January to December in 2007,the distribution and reserves of the region's wind energy resources were studied. [Result] The results showed that environmental wind speed was relatively stable in central and west Hexi Corridor. There were no distinct changes in climate characteristics distribution. There were regional differences in the distribution of wind energy,and there was a large numerical area of wind energy in Gazhou County and Yumen City; Wind energy in the region generally was higher. The wind energy density was above 100 w/m2 in the 10 m layer,around 140 w/m2 in most places,and was more than 200 w/m2 in the large number area. The wind grew in vertical direction along with the linear growth of height. Each 10 m high wind increased to 15 w/m2 averagely,50m layer wind energy was greater than the general 240 w/m2 and there were obvious changes on daily and annual with wind energy in central and west area of Hexi Corridor. The duration from March to May was a wind energy-intensive stage,10m height from the ground in the wind around 10:00 in low-value. After growing from 11:00,it met the day largest number at 18:00,and then reduced gradually. Effective wind speed hours in the region in general were more than 6 200 h,and the value in the large areas was close to 7 600 h. [Conclusion] The study laid basis for the development and application of wind energy in central and west area of Hexi Corridor.
文摘A method was introduced to assess the sustainability of energy production over the lifetime (~20 y) of wind turbines. Community Earth System Model simulations were downscaled for the tourist seasons (mid-May to mid-September) of 2006 to 2012 (CESM-P1) and 2026 to 2032 (CESM-P2) to obtain a reference and projected wind-speed climatology, respectively. The wind speeds served to calculate the potential power output and capacity factors of seven turbine types. CESM-P1 wind-speed climatology, power output, and capacity factors were compared to those derived from wind speeds obtained by numerical weather forecasts for reference to known standard to wind-farm managers. Juneau, Alaska served as a virtual testbed as this region is known to experience changes in wind speeds in response to the Pacific Decadal Oscillation. CESM-P2 suggested about 2% decrease for wind speeds between the speeds at cut-in and rated power, and about 8% - 10% decrease in potential wind-power output. This means that in regions of decadal climate variations, the sustainability of wind-energy production should be part of the decision-making process. The study demonstrated that using mean values of wind-speeds can provide qualitative knowledge about decreases/increases in potential energy production, but not about the magnitude. Using the total individual wind-speed data of all seasons provided the same amount of total power output than summing up the power outputs of individual seasons. The main advantage of calculating individual seasonal wind-power outputs, however, is that it theoretically permits assessment of interannual variability in power output and capacity factors. Comparison to a known standard may help stakeholders in understanding of uncertainty and interpretation of projected changes.
文摘The exploitation of wind energy is rapidly evolving and is manifested in the ever-expanding global network of offshore wind energy farms.For the Small Island Developing States of the Caribbean Sea(CS),harnessing this mature technology is an important first step in the transition away from fossil fuels.This paper uses buoy and satellite observations of surface wind speed in the CS to estimate wind energy resources over the 2009–201911-year period and initiates hour-ahead forecasting using the long short-term memory(LSTM)network.Observations of wind power density(WPD)at the 100-m height showed a mean of approximately 1000 W/m^(2) in the Colombia Basin,though this value decreases radially to 600–800 W/m^(2) in the central CS to a minimum of approximately 250 W/m^(2) at its borders in the Venezuela Basin.The Caribbean Low-Level Jet(CLLJ)is also responsible for the waxing and waning of surface wind speed and as such,resource stability,though stable as estimated through monthly and seasonal coefficients of variation,is naturally governed by CLLJ activity.Using a commercially available offshore wind turbine,wind energy generation at four locations in the CS is estimated.Electricity production is greatest and most stable in the central CS than at either its eastern or western borders.Wind speed forecasts are also found to be more accurate at this location,and though technology currently restricts offshore wind turbines to shallow water,outward migration to and colonization of deeper water is an attractive option for energy exploitation.
基金Project for Popularization of Advanced Meteorological Technology for 2006, China Meteorological Administration (CMATG2006M41)
文摘With high resolution (1 kin), the distribution of wind energy resources in Hainan province and over its offshore waters is numerically simulated by using the Wind Energy Simulation Toolkit (WEST) model developed by Meteorological Research Branch of Environment Canada. Compared with observations from eight coastal anemometric towers and 18 existing stations in the province, the simulations show good reproduction of the real distribution of wind resources in Hainan and over its offshore waters, with the relative error of annual mean wind speed being no more than 9% at the 70-m level. Moreover, based on the simulated results of WEST grids that are closest to where the eight wind towers are located, the annual mean wind speeds are further estimated by using the Danish software Wasp (Wind Atlas Analysis and Application Program). The estimated results are then compared with the observations from the towers. It shows that the relative error is also less than 9%. Therefore, WEST and WEST+WAsP will be useful tools for the assessment of wind energy resources in high resolution and selection of wind farm sites in Hainan province and over its offshore waters.
文摘Wind energy development receives broad support but is often opposed at the local level due to nuisance concerns and uncertainties about how it affects the landowners living due to the turbines and the broader community.Lo-cal opposition to wind energy development can be a powerful force slowing or even ending its implementation in a given region.Oklahoma,USA is currently ranked as 4^(th)in the United States in current wind energy production and has seen significant pushback from some local communities as a renewable energy resource.Previous studies have examined wind energy development’s impact on rural education income,and property values of different communities in Oklahoma.However,funding information on how wind energy development affects the individu-als living alongside the turbines are limited.Using fifteen interviews with landowners,site-managers,community representatives,and pro-wind non-profit organization representatives,this study finds that individuals who live in proximity to wind energy development,particularly those involved in the agricultural industry,have created novel and unique uses for wind farm infrastructure.It also finds that local perceptions of wind energy production are mostly positive and provides increased knowledge of how wind energy development affects the individuals and communities that are hosting the turbines and related infrastructure.
基金The authors gratefully acknowledge the financial support from the Natural Science Foundation of Chongqing(Grant No.cstc2017jcyjAX0307)the Fundamental Research Funds for the Central Universities(Grant Nos.CYFH201821,2020CDCGJ005,2018CDQYWL0046,2019CDXZWL001)the National Natural Science Foundation of China(Grant No.51402112).
文摘Wind energy is one of the most promising and renewable energy sources;however,owing to the limitations of device structures,collecting low-speed wind energy by triboelectric nanogenerators(TENGs)is still a huge challenge.To solve this problem,an ultra-durable and highly efficient windmill-like hybrid nanogenerator(W-HNG)is developed.Herein,the W-HNG composes coupled TENG and electromagnetic generator(EMG)and adopts a rotational contact-separation mode.This unique design efficiently avoids the wear of friction materials and ensures a prolonged service life.Moreover,the generator group is separated from the wind-driven part,which successfully prevents rotation resistance induced by the friction between rotor and stator in the conventional structures,and realizes low-speed wind energy harvesting.Additionally,the output characteristics of TENG can be complementary to the different performance advantages of EMG to achieve a satisfactory power production.The device is successfully driven when the wind speed is 1.8 m s−1,and the output power of TENG and EMG can achieve 0.95 and 3.7 mW,respectively.After power management,the W-HNG has been successfully applied as a power source for electronic devices.This work provides a simple,reliable,and durable device for improved performance toward large-scale low-speed breeze energy harvesting.
文摘Greenhouse gas emissions are the main cause of today's climate change. To address this problem, the world is in an era of new round energy transformation, and the existing energy structure is being reformed. In this paper, according to the Chinese government's action plan for coping with climate change, the China's wind energy sustainable development goals and development route are discussed, and the countermeasures and suggestions are put forward. Wind energy is currently a kind of important renewable energy with matured technology which can be scale-up developed and put into commercial application, and in this transformation, wind energy will play a key role with other non-fossil energy sources. The development and utilization of wind energy is a systematic project, which needs to be solved from the aspects of policy, technology and management. At present, China is in the stage of transferring from "large wind power country" to "strong wind power country", opportunities and challenges coexist, and the advantages of China's socialist system could be fully used, which can concentrate power to do big things and make contribution in the process of realizing global energy transformation.
文摘Based on the analysis of ocean dynamic condition and sediment environment, conclusions can be drawn that strong wind is an essential factor influencing sudden sedimentation in outer channel. Through theoretical analysis, it changes the complex process that wind raises wave, wave tilts sediment and current transports sediment into a comprehensive factor, and obtains mathematical formula between effective wind energy and the thickness of sudden sedimentation. The parametees in this formula are determined with field data of Huanghua Port. It may be used to predict siltation thickness and volume along the channel. By analyzing and comparing the difference in ocean hydrodynamic conditions and seabed material between Huanghua Port and Binzhou Port, the proposed formula can be used to predict sudden sedimentation in Binzhou Port and the calculated results is rehable. By predicting it on different combination plans among different recurrence in- tervals, entrance locations and channel classes, it provides references for the plane design of Binzhou Port.
基金the financial support from National Natural Science Foundation of China Grant No.61604023National Natural Science Foundation of China(Grant No.61804016)。
文摘Following the current rapid development of the Internet of Things(IoT)and wireless condition monitoring systems,energy harvesters which use ambient energy have become a key part of achieving an energy-autonomous system.Miniature wind energy harvesters have attracted widespread attention because of their great potential of power density as well as the rich availability of wind energy in many possible areas of application.This article provides readers with a glimpse into the state-of-the-art of miniature wind energy harvesters.The crucial factors for them to achieve high working efficiency under lower operational wind speed excitation are analyzed.Various potential energy coupling mechanisms are discussed in detail.Design approaches for broadening operational wind-speed-range given a variety of energy coupling mechanisms are also presented,as observed in the literature.Performance enhancement mechanisms including hydrodynamic configuration optimization,and non-linear vibration pick-up structure are reviewed.Conclusions are drawn and the outlook for each coupling mechanisms is presented.