The typical location and number of anemometer towers in the assessed area are the key to the accuracy of wind resource assessment in complex topography.As calculation examples,this paper used two typical complex topog...The typical location and number of anemometer towers in the assessed area are the key to the accuracy of wind resource assessment in complex topography.As calculation examples,this paper used two typical complex topography wind farms in Guangxi,Yunnan province in China.Firstly,we simulated the wind resource status of the anemometer tower in the Meteodyn WT software.Secondly,we compared the simulated wind resource with the actual measured data by the anemometer tower in the same situation.Thirdly,we analyzed the influence of anemometer tower location and quantity in the accuracy of wind resource assessment through the comparison results.The results showed that the range which the anemometer tower can represent is limited(<5 kilometers),and the prediction error more than 5%.Besides,the anemometer towers in special terrain areas(such as wind acceleration areas)cannot be used as a representative choice.The relative error of the simulated average annual wind speed by choose different number of anemometer towers is about 4%,and the grid-connected power generation more than 6%.The representative effect of anemometer towers is of crucial for improving the accuracy of wind resource assessment in engineering applications.展开更多
China’s recently announced directive on tackling climate change,namely,to reach carbon peak by 2030 and to achieve carbon neutrality by 2060,has led to an unprecedented nationwide response among the academia and indu...China’s recently announced directive on tackling climate change,namely,to reach carbon peak by 2030 and to achieve carbon neutrality by 2060,has led to an unprecedented nationwide response among the academia and industry.Under such a directive,a rapid increase in the grid penetration rate of solar in the near future can be fully anticipated.Although solar radiation is an atmospheric process,its utilization,as to produce electricity,has hitherto been handled by engineers.In that,it is thought important to bridge the two fields,atmospheric sciences and solar engineering,for the common good of carbon neutrality.In thisüberreview,all major aspects pertaining to solar resource assessment and forecasting are discussed in brief.Given the size of the topic at hand,instead of presenting technical details,which would be overly lengthy and repetitive,the overarching goal of this review is to comprehensively compile a catalog of some recent,and some not so recent,review papers,so that the interested readers can explore the details on their own.展开更多
Objective Traditional oil and gas theory considers that hydrocarbon generation process is a hydrodeoxygenation reaction of organic matter(OM).Thus,the supply condition of hydrogen controls the hydrocarbon generation a...Objective Traditional oil and gas theory considers that hydrocarbon generation process is a hydrodeoxygenation reaction of organic matter(OM).Thus,the supply condition of hydrogen controls the hydrocarbon generation ability of OM.Those factors of TOC and hydrogen index(I_H)are playing important roles for calculating展开更多
As the global demand for renewable energy grows,solar energy is gaining attention as a clean,sustainable energy source.Accurate assessment of solar energy resources is crucial for the siting and design of photovoltaic...As the global demand for renewable energy grows,solar energy is gaining attention as a clean,sustainable energy source.Accurate assessment of solar energy resources is crucial for the siting and design of photovoltaic power plants.This study proposes an integrated deep learning-based photovoltaic resource assessment method.Ensemble learning and deep learning methods are fused for photovoltaic resource assessment for the first time.The proposed method combines the random forest,gated recurrent unit,and long short-term memory to effectively improve the accuracy and reliability of photovoltaic resource assessment.The proposed method has strong adaptability and high accuracy even in the photovoltaic resource assessment of complex terrain and landscape.The experimental results show that the proposed method outperforms the comparison algorithm in all evaluation indexes,indicating that the proposed method has higher accuracy and reliability in photovoltaic resource assessment with improved generalization performance traditional single algorithm.展开更多
The development of offshore wind farms has experienced rapid growth during the past decade. In particular, China has the highest number of installations worldwide, but some challenges exist for further development. Co...The development of offshore wind farms has experienced rapid growth during the past decade. In particular, China has the highest number of installations worldwide, but some challenges exist for further development. Consequently, some researchers suggest combining wave energy with offshore wind energy. To fully implement this plan, a comprehensive resource assessment of combined offshore wind and wave energy systems is needed. Investigations of the parameters, such as the spatial and temporal distribution of wind and wave energy, aggregate resource reserves, available technical potential, and total capacity factor, are vital for designing the required wind turbines and wave energy converters. To assist scientific development and governmental decision making, this paper aims to evaluate offshore wind and wave energy resources from a technological perspective. The results show that theoretical offshore wind and wave energy resources are abundant in China's ocean territory, with a potential of approximately 3 TW. Technically, of the three most popular offshore wind turbines, i.e., 6, 8, and 10 MW, 10 MW is overall the most suitable in China. However, of the three wave energy converters, i.e., 120, 250, and 750 kW, 120 kW is the best candidate for Liaoning Province, and 750 kW is the most suitable for the remainder of its region. Overall, the total annual energy production is approximately 7000 TWh.展开更多
With the increasing severity of environmental problems,many countries have set energy transition targets to promote the realization of the Paris Agreement.There has been a global consensus on utilizing solar energy re...With the increasing severity of environmental problems,many countries have set energy transition targets to promote the realization of the Paris Agreement.There has been a global consensus on utilizing solar energy resources as alternatives to conventional sources to support this energy transition.In this regard,analyzing the“location,”“quantity,”and“quality”of global solar energy resources will not only assist an individual country to efficiently utilize these resources but also promote the realization of large-scale intercontinental resource utilization and complementation.This study established the basic database,model methods,and platform tools for global solar energy assessment,Then,a global solar energy resource assessment was conducted,which included the theoretical reserves(TRs),technical installed potential capacity(TPIC),and average development cost(ADC).A comparative analysis of the assessment results for all continents was also performed.After that,based on big data analysis and geographic information system(GIS)calculations,the distribution characteristics of the global solar power TPIC were calculated with the two core indicators,namely the capacity factor and ADC.Furthermore,a data-driven quantitative evaluation of the refined development potential of solar energy resources was performed.Finally,the reasonableness and coincidence analysis of the resource assessment results were verified using data from global and specifically Chinese photovoltaic(PV)bases.展开更多
An unstructured model FVCOM(The Unstructured Grid Finite Volume Community Ocean Model)with sink momentum term was applied to simulate the tidal current field in Zhoushan Archipelago,China,with focus on the region name...An unstructured model FVCOM(The Unstructured Grid Finite Volume Community Ocean Model)with sink momentum term was applied to simulate the tidal current field in Zhoushan Archipelago,China,with focus on the region named PuHu Channel between Putuo Island and Hulu Island.The model was calibrated with several measurements in the channel,and the model perform-ance was validated.An examination of the spatial and temporal distributions of tidal energy resources based on the numerical simula-tion revealed that the greatest power density of tidal energy during spring tide is 3.6kWm^(−2)at the northern area of the channel.Two parameters were introduced to characterize the generation duration of the tidal array that causes the temporal variation of tidal current energy.The annual average available energy in the channel was found to be approximately 2.6MW.The annual generating hours at rated power was found to be 1800 h when the installed capacity of tidal array is approximately 12MW.A site for the tidal array with 25 turbines was selected,and the layout of the array was configured based on the EMEC specifications.Hydrodynamic influence due to the deployment of the tidal array was simulated by the modified FVCOM model.The simulation showed that the tidal level did not significantly change because of the operation of the tidal array.The velocity reduction covered a 2km^(2)area of the downstream the tidal array,with a maximum velocity reduction of 8cms−1 at mid-flood tide,whereas the streamwise velocity on both sides of the farm increased slightly.展开更多
Energy is one of the most important factors in socio-economic development.The rapid increase in energy demand and air pollution has increased the number of ways to generate energy in the power sector.Currently,wind en...Energy is one of the most important factors in socio-economic development.The rapid increase in energy demand and air pollution has increased the number of ways to generate energy in the power sector.Currently,wind energy capacity in Ethiopia is estimated at 10,000 MW.Of these,however,only eight percent of its capacity has been used in recent years.One of the reasons for the low use of wind energy is the lack of accurate wind atlases in the country.Therefore,the purpose of this study is to develop an accurate wind atlas and review the wind resources using Wind Atlas Analysis and Application Program in Dangla so that the best sites used for the installation of wind farms can be easily identified.Wind climatology data,vector maps,and wind turbine data were used to model the Wind Atlas Analysis and Application Program.The wind data collected from National Meteorology Survey Agency over three years were used for the analysis.Besides,vector data for the survey area was prepared using Global Mapper V20.1.In this study,the Wind Atlas Analysis and Application Program tool was used to estimate wind resources.The wind resource map was developed at an altitude of 80 m above ground level,and a horizontal axis type wind generator called(i.e.,GridStreamer Vestas V1001.8 MW)was selected from the Wind Atlas Analysis and Application Program catalog to mimic the wind farm.The results obtained from the analysis of actual wind data showed that the minimum wind speed was 0.12083 m/s while the maximum wind speed was 9.96389 m/s.At a height of 10 m a.g.l.,the mean wind speed and wind power density were 1.8 m/s and 9 w/m2,respectively.The most common wind direction was also discovered to be 210 degrees.The maximum wind speed and capacity factor were available around hills,according to the wind resource map,and the net annual energy output of the Dangla wind farm at a turbine height of 80 m a.g.l.was found to be 282.726 GWh(or,32.27 MW).The farm’s capacity factor was also discovered to be 9.54 percent,indicating that the site is rated as low potential.展开更多
The China National Administration of Coal Geology accomplished an assessment of coalbed methaneresources of China in 1988. The total amount of coalbed methane resources in China is 14336.944 billion m , occurring in r...The China National Administration of Coal Geology accomplished an assessment of coalbed methaneresources of China in 1988. The total amount of coalbed methane resources in China is 14336.944 billion m , occurring in recoverable coal seams and beneath weathering zones, with coalbed methane content equal to or higher than 4 m3 per ton and buried depths smaller than 2000 m, among which there are 967.51 billion m of predicted reserves and 13369.434 billion m of future reserves. The resources in coal reservoirs with methane content of more than 8 m per ton are 12444.087 billion m , and those with methane content between 4 to 8 m per ton are 1892.856 billion m . There are 35 districts in which the resources abundance is higher than 150 million m3 /km2 , 49 districts with the abundance between 50 million and 150 million m 3/km2 , and 31 districts with the abundance less than 50 million m3 /km2 . There is 9256.078 billion m3 of methane occurring in coal seams with buried depths less than 1500 m, and 5080.866展开更多
Near-bottom observation data from the manned deep submersible Jiaolong with high-precision underwater positioning data from Weijia Guyot,Magellan Seamounts in the Western Pacific Ocean are reported.Three substrate typ...Near-bottom observation data from the manned deep submersible Jiaolong with high-precision underwater positioning data from Weijia Guyot,Magellan Seamounts in the Western Pacific Ocean are reported.Three substrate types were identified:Sediment,ferromanganese crust,and ferromanganese crust with a thin cover of sediment.The ferromanganese crusts show clear zoning and their continuity is usually disturbed by sediments on areas of the mountainside with relatively gentle slope gradients.The identified substrate spatial distributions correspond to acoustic backscatter intensity data,with regions of high intensity always including crust development and regions of low intensity always having sediment.Therefore,acoustic backscatter intensity surveying appears useful in the delineation and evaluation of crust resources,although further more work is needed to develop a practicable methodology.展开更多
Based on Investigation and Assessment on Rational Exploitation and Utilization of Groundwater Resources in Typical Areas of the Hexi Corridor, the thesis studies on groundwater and environmental problems arising from ...Based on Investigation and Assessment on Rational Exploitation and Utilization of Groundwater Resources in Typical Areas of the Hexi Corridor, the thesis studies on groundwater and environmental problems arising from the large-scale agricultural development projects in Shule River Basin. The thesis analyzes problems in exploiting and utilizing water resources, defines the function zoning of groundwater resources in key areas and evaluates them. Finally, the thesis uses three-dimensional unsteady flow simulation and regional social and economic development plan to study on the allocation of groundwater in Shule River Basin. A proposal for rational allocation of Shule River Basin water resources has been put forward.展开更多
The Qinghai-Tibet Plateau(also referred to as the Plateau)has long received much attention from the community of geoscience due to its unique geographical location and rich mineral resources.This paper reviews the aer...The Qinghai-Tibet Plateau(also referred to as the Plateau)has long received much attention from the community of geoscience due to its unique geographical location and rich mineral resources.This paper reviews the aeromagnetic surveys in the Plateau in the past 60 years and summarizes relevant research achievements,which mainly include the followings.(1)The boundaries between the Plateau and its surrounding regions have been clarified.In detail,its western boundary is restricted by West Kunlun-Altyn Tagh arc-shaped magnetic anomaly zone forming due to the arc-shaped connection of the Altyn Tagh and Kangxiwa faults and its eastern boundary consists of the boundaries among different magnetic fields along the Longnan(Wudu)-Kangding Fault.Meanwhile,the fault on the northern margin of the Northern Qilian Mountains serves as its northern boundary.(2)The Plateau is mainly composed of four orogens that were stitched together,namely East Kunlun-Qilian,Hoh-Xil-Songpan,Chamdo-Southwestern Sanjiang(Nujiang,Lancang,and Jinsha rivers in southeastern China),and Gangdese-Himalaya orogens.(3)The basement of the Plateau is dominated by weakly magnetic Proterozoic metamorphic rocks and lacks strongly magnetic Archean crystalline basement of stable continents such as the Tarim and Sichuan blocks.Therefore,it exhibits the characteristics of unstable orogenic basement.(4)The Yarlung-Zangbo suture zone forming due to continent-continent collisions since the Cenozoic shows double aeromagnetic anomaly zones.Therefore,it can be inferred that the Yarlung-Zangbo suture zone formed from the Indian Plate subducting towards and colliding with the Eurasian Plate twice.(5)A huge negative aeromagnetic anomaly in nearly SN trending has been discovered in the middle part of the Plateau,indicating a giant deep thermal-tectonic zone.(6)A dual-layer magnetic structure has been revealed in the Plateau.It consists of shallow magnetic anomaly zones in nearly EW and NW trending and deep magnetic anomaly zones in nearly SN trending.They overlap vertically and cross horizontally,showing the flyover-type geological structure of the Plateau.(7)A group of NW-trending faults occur in eastern Tibet,which is intersected rather than connected by the nearly EW trending that develop in middle-west Tibet.(8)As for the central uplift zone that occurs through the Qiangtang Basin,its metamorphic basement tends to gradually descend from west to east,showing the form of steps.The Qiangtang Basin is divided into the northern and southern part by the central uplift zone in it.The basement in the Qiangtang Basin is deep in the north and west and shallow in the south and west.The basement in the northern Qiangtang Basin is deep and relatively stable and thus is more favorable for the generation and preservation of oil and gas.Up to now,19 favorable tectonic regions of oil and gas have been determined in the Qiangtang Basin.(9)A total of 21 prospecting areas of mineral resources have been delineated and thousands of ore-bearing(or mineralization)anomalies have been discovered.Additionally,the formation and uplift mechanism of the Plateau are briefly discussed in this paper.展开更多
The research on tight oil becomes another hotspot in the field of unconventional oil and gas after the boom of shale gas.The global recoverable resources of tight oil are estimated to be around 47.3×10^(9)t.In re...The research on tight oil becomes another hotspot in the field of unconventional oil and gas after the boom of shale gas.The global recoverable resources of tight oil are estimated to be around 47.3×10^(9)t.In recent years,significant progress has been made in the technologies of tight oil exploration and development in North America,thus stimulating the dramatic increase of tight oil production.Meanwhile,China has also acquired remarkable achievements in tight oil exploration.Mature assessment methods have been established for tight oil resources by the US,generally dominated by analogy and statistical methods with their own advantages and disadvantages as well as applicable conditions.In China,improvement of resource evaluation techniques becomes an urgent issue in increasing tight oil reserve and production.This study mainly discusses the resource evaluation methods and resource enrichment characteristics of tight oil.Seven kinds of assessment methods in three categories(i.e.,analogy,statistical and genetic method)and evaluation parameters have been preliminary established,and are specifically applied in the Sichuan,Ordos,Songliao,Junggar,Bohai Bay and other tight oil basins through the newly hierarchical resource abundance analogy method,the estimated ultimate recovery(EUR)analogy method and the small-cell volumetric method.The preliminary evaluation results reveal that China has great potential in tight oil resource,and the geological resources amount to 20×10^(9)t,providing a resource base for large-scale development.展开更多
The Badain Jaran Desert is the third largest desert in China,covering an area of 50000 km2.It lies in Northwest China,where the arid and rainless natural environment has a great impact on the climate,environment,and h...The Badain Jaran Desert is the third largest desert in China,covering an area of 50000 km2.It lies in Northwest China,where the arid and rainless natural environment has a great impact on the climate,environment,and human living conditions.Based on the results of 1∶250000 regional hydrogeological surveys and previous researches,this study systematically investigates the circulation characteristics and resource properties of the groundwater as well as the evolution of the climate and ecological environment since the Quaternary in the Badain Jaran Desert by means of geophysical exploration,hydrogeological drilling,hydrogeochemistry,and isotopic tracing.The results are as follows.(1)The groundwater in the Badain Jaran Desert is mainly recharged through the infiltration of local precipitation and has poor renewability.The groundwater recharge in the desert was calculated to be 1.8684×10^(8)m^(3)/a using the water balance method.(2)The Badain Jaran Desert has experienced four humid stages since the Quaternary,namely MIS 13-15,MIS 5,MIS 3,and the Early‒Middle Holocene,but the climate in the desert has shown a trend towards aridity overall.The average annual temperature in the Badain Jaran Desert has significantly increased in the past 50 years.In detail,it has increased by about 2.5℃,with a higher rate in the south than in the north.Meanwhile,the precipitation amount has shown high spatial variability and the climate has shown a warming-drying trend in the past 50 years.(3)The lakes in the hinterland of the Badain Jaran Desert continuously shrank during 1973‒2015.However,the vegetation communities maintained a highly natural distribution during 2000‒2016,with the vegetation cover has increased overall.Accordingly,the Badain Jaran Desert did not show any notable expansion in that period.This study deepens the understanding of groundwater circulation and the climate and ecological evolution in the Badain Jaran Desert.It will provide a scientific basis for the rational exploitation of the groundwater resources and the ecological protection and restoration in the Badain Jaran Desert.展开更多
Tidal current power is one of the promising and reliable renewable energies with the advantage of continuous and predictable resource. It can make stable electricity regardless of weather conditions or seasons all yea...Tidal current power is one of the promising and reliable renewable energies with the advantage of continuous and predictable resource. It can make stable electricity regardless of weather conditions or seasons all year around. The required technologies for tidal current power in the ocean have been developed for years and now recognized that it could be commercialized after intensive field tests and successful demonstrations. There are several tidal farm development projects in the world, such as the MeyGen project in UK with its commercialization at hand. However, various research subjects in the tidal current energy field are seeking improvements and industrialization of tidal current power in terms of economy and technical reliability. This paper introduces the resource assessment procedure of tidal energy that has been applied in Korea coastal regions. The key research subjects for tidal current power together with the interaction effect of multi-arrangement is described. Also, this paper is to introduce the research output of each subject such as turbine design, experimental validation, turbine interaction and wake, multi-array module, FSI (fluid-structure interaction), and duct application.展开更多
Potential revenue from wind power generation is an important factor to be considered when planning a wind power investment.In the future,that may become even more important because it is known that wind power generati...Potential revenue from wind power generation is an important factor to be considered when planning a wind power investment.In the future,that may become even more important because it is known that wind power generation tends to push electricity wholesale prices lower.Consequently,it is possible that if a region has plenty of installed wind power capacity,revenue per generated unit of electricity is lower there than could be assumed by looking at the mean electricity wholesale price.In this paper,we compare 17 different locations in Finland in terms of revenue from wind power generation.That is done by simulating hourly generation with three different turbine types at two different hub heights and multiplying that by the hourly electricity spot price for years 2018 and 2019.Estimated revenues differ greatly between locations and turbine types,major factor being technical potential i.e.,the amount of electricity generated.Differences between revenues per generated MWh seem to be small,however,the smallest figures being on the western coast where installed capacities are also the largest in Finland.展开更多
Appropriate information on solar resources is very important for a variety of technological areas, such as agriculture, meteorology, forestry engineering, and water resources, particularly for an innovative technology...Appropriate information on solar resources is very important for a variety of technological areas, such as agriculture, meteorology, forestry engineering, and water resources, particularly for an innovative technology such as solar energy. In the market entry process of an innovative technology such as solar energy, the increased and sustained deployment of this energy technology strongly depends on the economy and reliability of the solar systems installed. The economy and reliability of a system are the consequences of a well-prepared project, resulting from an accurate knowledge of the solar resource available. Therefore, knowing the potential of the solar resource accurately is not only a need but also an imperative for the larger diffusion and use of the solar energy. The existing sources of the information on radiation in MG are quite varied, both at the institutional level and in different types of publications. The publications containing this information are project reports, internal reports of institutions, and several magazines. Thus, the quality of the data varies considerably, the information presents spatial and temporal discontinuity;moreover, the instruments and the measurement units are not standardised. The general objective of this paper is to recover, to qualify, to standardize, and to make available the best information from the current existing solar resource in MG, Brazil, either in the form of isoline charts of solar radiation or a numerical database. In this paper, the procedure to elaborate the maps of daily solar radiation and insolation, along with the monthly and annual averages, is described. We present one map with the localisation of the recording stations in addition to one annual and 12 monthly contour maps. The map of the daily global solar irradiation and the annual average determined in this project show that solar radiation on the state of Minas Gerais ranges from 4.5 to 6.5 kWh/m2. The maximum values occur in the northern region of Minas Gerais, and the minimum values occur in the southeast region, where there are areas of higher altitude (Mantiqueira and Serra do Caparaó) and the rainfall is more intense, with total annual rainfall greater than 1400 mm. The North and Northeast Regions of MG, where the largest annual irradiation of 6.5 kWh/m2 occurs, are characterised by a semiarid climate with annual rainfall between 600 - 800 mm and altitudes between 400 - 600 m. The maritime tropical air mass that acts between Brazil and Africa is the main climatic factor that inhibits cloud formation and, consequently, the rainfall in this region. Finally, the map of annual insolation reveals a consistent correlation between the daily rainfall and the solar radiation annual average.展开更多
The North China district has been subjected to significant research with regard to the ore-forming dynamics,processes,and quantitative forecasting of gold deposits;it accounts for the highest number of gold reserves a...The North China district has been subjected to significant research with regard to the ore-forming dynamics,processes,and quantitative forecasting of gold deposits;it accounts for the highest number of gold reserves and annual products in China.Based on the top-level design of geoscience theory and the method adopted by the National Key R&D Project(deep process and metallogenic mechanism of North China Craton(NCC)metallogenic system),this paper systematically collects and constructs the geoscience data(district,camp,and deposit scales)in four key gold districts of North China(Jiaojia-Sanshandao,Southern Zhaoping,Wulong,and Qingchengzi).The settings associated with the geological dynamics of gold deposits were quantitatively and synthetically analyzed,namely:NCC destruction,metallogenic events,genetic models,and exploration models.Three-dimensional(3D)and four-dimensional(4D)geological modeling was performed using the big data on the districts,while the district-scale 3D exploration criteria were integrated to construct a quantitative exploration model.Among them,FLAC3D modelling and the Geo Cube software(version 3.0)were used to implement the numerical simulation of the 3D geological models and the constraints of the fluid saturation parameters of the Jiaojia fault to reconstruct the 4D fault structure models of the Jiaojia fault(with a depth of 5000 m).Using Geo Cube3.0,multiple integration modules(general weights of evidence(Wof E),Boost Wof E,Fuzzy Wof E,Logistic Regression,Information Entropy,and Random Forest)and exploration criteria were integrated,while the C-V fractal classification of A,B and C targets in four districts was carried out.The research results are summarized in the following four areas:(1)Four gold districts in the study area have more than three targets(the depth is 3000 m),and the class A,B and C targets exhibit a good spatial correlation with gold bodies that are controlled by mining engineering at depths greater than 1000 m.(2)The Boost Wof E method was used to identify the target optimization in 3D spaces(at depths of 3000–5000 m)of the Jiaojia-Sanshandao,Southern Zhaoping,and Wulong districts.(3)The general Wof E method is based on the Bayesian theory in 3D space and provides robust integration and target optimization that are suitable for the Jiaojia-Sanshandao and Southern Zhaoping districts in the Jiaodong area;it can also be applied to the Wulong district in the Liaodong area using a quantitative genetic model and an exploration model.Random forest is a multi-objective integration and target optimization method for 3D spaces,and it is suitable for the complex exploration model in the Qingchengzi district of the Liaodong area.The genetic model and exploration criteria associated with the exploration model of the Qingchengzi district were constrained by the common characteristics of the gold fault structure,magmatic rock emplacement in North China,and the strata fold and interlayer detachment structure.(4)Based on the gold reserves and the 3D block unit model of the Sanshandao gold deposit in the Jiaojia-Sanshandao district,the gold contents of the 3D block units in class A and B targets of the ore concentration were estimated to be 65.5%and 25.1%,respectively.The total Au resources of the optimized targets below a depth of 3000 m were 3908 t(including 1700 t reserves),and the total Au resources of the targets at depths from 3000 to 5000 m were 936 t.The study shows that the deep gold deposits in the four gold districts of North China exhibit a strong"transport-deposition"spatial correlation with potential targets.These"transport-deposition"spatial models represent the tectonic-magmatic-hydrothermal activities of the metallogenic system associated with the NCC destruction events and indicate the Au enrichment zones.展开更多
基金the financial support by the National Natural Science Foundation of China(No.52176212).
文摘The typical location and number of anemometer towers in the assessed area are the key to the accuracy of wind resource assessment in complex topography.As calculation examples,this paper used two typical complex topography wind farms in Guangxi,Yunnan province in China.Firstly,we simulated the wind resource status of the anemometer tower in the Meteodyn WT software.Secondly,we compared the simulated wind resource with the actual measured data by the anemometer tower in the same situation.Thirdly,we analyzed the influence of anemometer tower location and quantity in the accuracy of wind resource assessment through the comparison results.The results showed that the range which the anemometer tower can represent is limited(<5 kilometers),and the prediction error more than 5%.Besides,the anemometer towers in special terrain areas(such as wind acceleration areas)cannot be used as a representative choice.The relative error of the simulated average annual wind speed by choose different number of anemometer towers is about 4%,and the grid-connected power generation more than 6%.The representative effect of anemometer towers is of crucial for improving the accuracy of wind resource assessment in engineering applications.
文摘China’s recently announced directive on tackling climate change,namely,to reach carbon peak by 2030 and to achieve carbon neutrality by 2060,has led to an unprecedented nationwide response among the academia and industry.Under such a directive,a rapid increase in the grid penetration rate of solar in the near future can be fully anticipated.Although solar radiation is an atmospheric process,its utilization,as to produce electricity,has hitherto been handled by engineers.In that,it is thought important to bridge the two fields,atmospheric sciences and solar engineering,for the common good of carbon neutrality.In thisüberreview,all major aspects pertaining to solar resource assessment and forecasting are discussed in brief.Given the size of the topic at hand,instead of presenting technical details,which would be overly lengthy and repetitive,the overarching goal of this review is to comprehensively compile a catalog of some recent,and some not so recent,review papers,so that the interested readers can explore the details on their own.
基金sponsored by National Science Foundation of China (grants No.41541019, 41230312 and 41102075)Strategic Priority Research Program of the Chinese Academy of Sciences (grant No.XDA14010404)Liu Baojun Geological Youth Foundation Project (grant No.DMSM2017053)
文摘Objective Traditional oil and gas theory considers that hydrocarbon generation process is a hydrodeoxygenation reaction of organic matter(OM).Thus,the supply condition of hydrogen controls the hydrocarbon generation ability of OM.Those factors of TOC and hydrogen index(I_H)are playing important roles for calculating
基金funded by Key-Area Research and Development Program Project of Guangdong Province (2021B0101230003)China Southern Power Grid Science and Technology Project (ZBKJXM20220004).
文摘As the global demand for renewable energy grows,solar energy is gaining attention as a clean,sustainable energy source.Accurate assessment of solar energy resources is crucial for the siting and design of photovoltaic power plants.This study proposes an integrated deep learning-based photovoltaic resource assessment method.Ensemble learning and deep learning methods are fused for photovoltaic resource assessment for the first time.The proposed method combines the random forest,gated recurrent unit,and long short-term memory to effectively improve the accuracy and reliability of photovoltaic resource assessment.The proposed method has strong adaptability and high accuracy even in the photovoltaic resource assessment of complex terrain and landscape.The experimental results show that the proposed method outperforms the comparison algorithm in all evaluation indexes,indicating that the proposed method has higher accuracy and reliability in photovoltaic resource assessment with improved generalization performance traditional single algorithm.
基金provided by the National Marine Renewable Energy Programs of Chinasupported by the National Key R&D Program of China(Grant No.2017YFE0132000)the National Natural Science Foundation of China(Grant Nos.52078251 and 42276228)。
文摘The development of offshore wind farms has experienced rapid growth during the past decade. In particular, China has the highest number of installations worldwide, but some challenges exist for further development. Consequently, some researchers suggest combining wave energy with offshore wind energy. To fully implement this plan, a comprehensive resource assessment of combined offshore wind and wave energy systems is needed. Investigations of the parameters, such as the spatial and temporal distribution of wind and wave energy, aggregate resource reserves, available technical potential, and total capacity factor, are vital for designing the required wind turbines and wave energy converters. To assist scientific development and governmental decision making, this paper aims to evaluate offshore wind and wave energy resources from a technological perspective. The results show that theoretical offshore wind and wave energy resources are abundant in China's ocean territory, with a potential of approximately 3 TW. Technically, of the three most popular offshore wind turbines, i.e., 6, 8, and 10 MW, 10 MW is overall the most suitable in China. However, of the three wave energy converters, i.e., 120, 250, and 750 kW, 120 kW is the best candidate for Liaoning Province, and 750 kW is the most suitable for the remainder of its region. Overall, the total annual energy production is approximately 7000 TWh.
基金supported by National Science and Technology Major Project(2018YFB0904000).
文摘With the increasing severity of environmental problems,many countries have set energy transition targets to promote the realization of the Paris Agreement.There has been a global consensus on utilizing solar energy resources as alternatives to conventional sources to support this energy transition.In this regard,analyzing the“location,”“quantity,”and“quality”of global solar energy resources will not only assist an individual country to efficiently utilize these resources but also promote the realization of large-scale intercontinental resource utilization and complementation.This study established the basic database,model methods,and platform tools for global solar energy assessment,Then,a global solar energy resource assessment was conducted,which included the theoretical reserves(TRs),technical installed potential capacity(TPIC),and average development cost(ADC).A comparative analysis of the assessment results for all continents was also performed.After that,based on big data analysis and geographic information system(GIS)calculations,the distribution characteristics of the global solar power TPIC were calculated with the two core indicators,namely the capacity factor and ADC.Furthermore,a data-driven quantitative evaluation of the refined development potential of solar energy resources was performed.Finally,the reasonableness and coincidence analysis of the resource assessment results were verified using data from global and specifically Chinese photovoltaic(PV)bases.
基金This work was supported by the National Key R&D Program of China(Nos.2019YFE0102500,2019YFB1504401,2019YFE0102500 and 2016YFC1401800).The au-thors would like to thank the FVCOM Development Group for their modeling support.
文摘An unstructured model FVCOM(The Unstructured Grid Finite Volume Community Ocean Model)with sink momentum term was applied to simulate the tidal current field in Zhoushan Archipelago,China,with focus on the region named PuHu Channel between Putuo Island and Hulu Island.The model was calibrated with several measurements in the channel,and the model perform-ance was validated.An examination of the spatial and temporal distributions of tidal energy resources based on the numerical simula-tion revealed that the greatest power density of tidal energy during spring tide is 3.6kWm^(−2)at the northern area of the channel.Two parameters were introduced to characterize the generation duration of the tidal array that causes the temporal variation of tidal current energy.The annual average available energy in the channel was found to be approximately 2.6MW.The annual generating hours at rated power was found to be 1800 h when the installed capacity of tidal array is approximately 12MW.A site for the tidal array with 25 turbines was selected,and the layout of the array was configured based on the EMEC specifications.Hydrodynamic influence due to the deployment of the tidal array was simulated by the modified FVCOM model.The simulation showed that the tidal level did not significantly change because of the operation of the tidal array.The velocity reduction covered a 2km^(2)area of the downstream the tidal array,with a maximum velocity reduction of 8cms−1 at mid-flood tide,whereas the streamwise velocity on both sides of the farm increased slightly.
文摘Energy is one of the most important factors in socio-economic development.The rapid increase in energy demand and air pollution has increased the number of ways to generate energy in the power sector.Currently,wind energy capacity in Ethiopia is estimated at 10,000 MW.Of these,however,only eight percent of its capacity has been used in recent years.One of the reasons for the low use of wind energy is the lack of accurate wind atlases in the country.Therefore,the purpose of this study is to develop an accurate wind atlas and review the wind resources using Wind Atlas Analysis and Application Program in Dangla so that the best sites used for the installation of wind farms can be easily identified.Wind climatology data,vector maps,and wind turbine data were used to model the Wind Atlas Analysis and Application Program.The wind data collected from National Meteorology Survey Agency over three years were used for the analysis.Besides,vector data for the survey area was prepared using Global Mapper V20.1.In this study,the Wind Atlas Analysis and Application Program tool was used to estimate wind resources.The wind resource map was developed at an altitude of 80 m above ground level,and a horizontal axis type wind generator called(i.e.,GridStreamer Vestas V1001.8 MW)was selected from the Wind Atlas Analysis and Application Program catalog to mimic the wind farm.The results obtained from the analysis of actual wind data showed that the minimum wind speed was 0.12083 m/s while the maximum wind speed was 9.96389 m/s.At a height of 10 m a.g.l.,the mean wind speed and wind power density were 1.8 m/s and 9 w/m2,respectively.The most common wind direction was also discovered to be 210 degrees.The maximum wind speed and capacity factor were available around hills,according to the wind resource map,and the net annual energy output of the Dangla wind farm at a turbine height of 80 m a.g.l.was found to be 282.726 GWh(or,32.27 MW).The farm’s capacity factor was also discovered to be 9.54 percent,indicating that the site is rated as low potential.
文摘The China National Administration of Coal Geology accomplished an assessment of coalbed methaneresources of China in 1988. The total amount of coalbed methane resources in China is 14336.944 billion m , occurring in recoverable coal seams and beneath weathering zones, with coalbed methane content equal to or higher than 4 m3 per ton and buried depths smaller than 2000 m, among which there are 967.51 billion m of predicted reserves and 13369.434 billion m of future reserves. The resources in coal reservoirs with methane content of more than 8 m per ton are 12444.087 billion m , and those with methane content between 4 to 8 m per ton are 1892.856 billion m . There are 35 districts in which the resources abundance is higher than 150 million m3 /km2 , 49 districts with the abundance between 50 million and 150 million m 3/km2 , and 31 districts with the abundance less than 50 million m3 /km2 . There is 9256.078 billion m3 of methane occurring in coal seams with buried depths less than 1500 m, and 5080.866
基金This studywas funded by the Resource and Environment COMRA Projects (DY135-C1-1-02,DY135-C1-1-01)the China Geological Survey(DD20191009).
文摘Near-bottom observation data from the manned deep submersible Jiaolong with high-precision underwater positioning data from Weijia Guyot,Magellan Seamounts in the Western Pacific Ocean are reported.Three substrate types were identified:Sediment,ferromanganese crust,and ferromanganese crust with a thin cover of sediment.The ferromanganese crusts show clear zoning and their continuity is usually disturbed by sediments on areas of the mountainside with relatively gentle slope gradients.The identified substrate spatial distributions correspond to acoustic backscatter intensity data,with regions of high intensity always including crust development and regions of low intensity always having sediment.Therefore,acoustic backscatter intensity surveying appears useful in the delineation and evaluation of crust resources,although further more work is needed to develop a practicable methodology.
基金the project Survey and Assessment of Water Resources Exploitation and Utilization in Characteristic Areas of the Hexi Corridor
文摘Based on Investigation and Assessment on Rational Exploitation and Utilization of Groundwater Resources in Typical Areas of the Hexi Corridor, the thesis studies on groundwater and environmental problems arising from the large-scale agricultural development projects in Shule River Basin. The thesis analyzes problems in exploiting and utilizing water resources, defines the function zoning of groundwater resources in key areas and evaluates them. Finally, the thesis uses three-dimensional unsteady flow simulation and regional social and economic development plan to study on the allocation of groundwater in Shule River Basin. A proposal for rational allocation of Shule River Basin water resources has been put forward.
基金funded by the National Key Research and Development Project(2017YFC0602200)China Geological Survey(DD20160065,DD20190025).
文摘The Qinghai-Tibet Plateau(also referred to as the Plateau)has long received much attention from the community of geoscience due to its unique geographical location and rich mineral resources.This paper reviews the aeromagnetic surveys in the Plateau in the past 60 years and summarizes relevant research achievements,which mainly include the followings.(1)The boundaries between the Plateau and its surrounding regions have been clarified.In detail,its western boundary is restricted by West Kunlun-Altyn Tagh arc-shaped magnetic anomaly zone forming due to the arc-shaped connection of the Altyn Tagh and Kangxiwa faults and its eastern boundary consists of the boundaries among different magnetic fields along the Longnan(Wudu)-Kangding Fault.Meanwhile,the fault on the northern margin of the Northern Qilian Mountains serves as its northern boundary.(2)The Plateau is mainly composed of four orogens that were stitched together,namely East Kunlun-Qilian,Hoh-Xil-Songpan,Chamdo-Southwestern Sanjiang(Nujiang,Lancang,and Jinsha rivers in southeastern China),and Gangdese-Himalaya orogens.(3)The basement of the Plateau is dominated by weakly magnetic Proterozoic metamorphic rocks and lacks strongly magnetic Archean crystalline basement of stable continents such as the Tarim and Sichuan blocks.Therefore,it exhibits the characteristics of unstable orogenic basement.(4)The Yarlung-Zangbo suture zone forming due to continent-continent collisions since the Cenozoic shows double aeromagnetic anomaly zones.Therefore,it can be inferred that the Yarlung-Zangbo suture zone formed from the Indian Plate subducting towards and colliding with the Eurasian Plate twice.(5)A huge negative aeromagnetic anomaly in nearly SN trending has been discovered in the middle part of the Plateau,indicating a giant deep thermal-tectonic zone.(6)A dual-layer magnetic structure has been revealed in the Plateau.It consists of shallow magnetic anomaly zones in nearly EW and NW trending and deep magnetic anomaly zones in nearly SN trending.They overlap vertically and cross horizontally,showing the flyover-type geological structure of the Plateau.(7)A group of NW-trending faults occur in eastern Tibet,which is intersected rather than connected by the nearly EW trending that develop in middle-west Tibet.(8)As for the central uplift zone that occurs through the Qiangtang Basin,its metamorphic basement tends to gradually descend from west to east,showing the form of steps.The Qiangtang Basin is divided into the northern and southern part by the central uplift zone in it.The basement in the Qiangtang Basin is deep in the north and west and shallow in the south and west.The basement in the northern Qiangtang Basin is deep and relatively stable and thus is more favorable for the generation and preservation of oil and gas.Up to now,19 favorable tectonic regions of oil and gas have been determined in the Qiangtang Basin.(9)A total of 21 prospecting areas of mineral resources have been delineated and thousands of ore-bearing(or mineralization)anomalies have been discovered.Additionally,the formation and uplift mechanism of the Plateau are briefly discussed in this paper.
基金This work was funded by Major Scientific and Technological Project of PetroChina(Grant No.2014E-050202).
文摘The research on tight oil becomes another hotspot in the field of unconventional oil and gas after the boom of shale gas.The global recoverable resources of tight oil are estimated to be around 47.3×10^(9)t.In recent years,significant progress has been made in the technologies of tight oil exploration and development in North America,thus stimulating the dramatic increase of tight oil production.Meanwhile,China has also acquired remarkable achievements in tight oil exploration.Mature assessment methods have been established for tight oil resources by the US,generally dominated by analogy and statistical methods with their own advantages and disadvantages as well as applicable conditions.In China,improvement of resource evaluation techniques becomes an urgent issue in increasing tight oil reserve and production.This study mainly discusses the resource evaluation methods and resource enrichment characteristics of tight oil.Seven kinds of assessment methods in three categories(i.e.,analogy,statistical and genetic method)and evaluation parameters have been preliminary established,and are specifically applied in the Sichuan,Ordos,Songliao,Junggar,Bohai Bay and other tight oil basins through the newly hierarchical resource abundance analogy method,the estimated ultimate recovery(EUR)analogy method and the small-cell volumetric method.The preliminary evaluation results reveal that China has great potential in tight oil resource,and the geological resources amount to 20×10^(9)t,providing a resource base for large-scale development.
基金This research was funded by projects of the National Natural Science Foundation of China(41702285)the National Geological Survey Project(121201106000150093)+1 种基金the National Natural Science Foundation of China(41807214)the Fundamental Scientific Research Funds from the Chinese Academy of Geological Sciences(No.SK202011).
文摘The Badain Jaran Desert is the third largest desert in China,covering an area of 50000 km2.It lies in Northwest China,where the arid and rainless natural environment has a great impact on the climate,environment,and human living conditions.Based on the results of 1∶250000 regional hydrogeological surveys and previous researches,this study systematically investigates the circulation characteristics and resource properties of the groundwater as well as the evolution of the climate and ecological environment since the Quaternary in the Badain Jaran Desert by means of geophysical exploration,hydrogeological drilling,hydrogeochemistry,and isotopic tracing.The results are as follows.(1)The groundwater in the Badain Jaran Desert is mainly recharged through the infiltration of local precipitation and has poor renewability.The groundwater recharge in the desert was calculated to be 1.8684×10^(8)m^(3)/a using the water balance method.(2)The Badain Jaran Desert has experienced four humid stages since the Quaternary,namely MIS 13-15,MIS 5,MIS 3,and the Early‒Middle Holocene,but the climate in the desert has shown a trend towards aridity overall.The average annual temperature in the Badain Jaran Desert has significantly increased in the past 50 years.In detail,it has increased by about 2.5℃,with a higher rate in the south than in the north.Meanwhile,the precipitation amount has shown high spatial variability and the climate has shown a warming-drying trend in the past 50 years.(3)The lakes in the hinterland of the Badain Jaran Desert continuously shrank during 1973‒2015.However,the vegetation communities maintained a highly natural distribution during 2000‒2016,with the vegetation cover has increased overall.Accordingly,the Badain Jaran Desert did not show any notable expansion in that period.This study deepens the understanding of groundwater circulation and the climate and ecological evolution in the Badain Jaran Desert.It will provide a scientific basis for the rational exploitation of the groundwater resources and the ecological protection and restoration in the Badain Jaran Desert.
文摘Tidal current power is one of the promising and reliable renewable energies with the advantage of continuous and predictable resource. It can make stable electricity regardless of weather conditions or seasons all year around. The required technologies for tidal current power in the ocean have been developed for years and now recognized that it could be commercialized after intensive field tests and successful demonstrations. There are several tidal farm development projects in the world, such as the MeyGen project in UK with its commercialization at hand. However, various research subjects in the tidal current energy field are seeking improvements and industrialization of tidal current power in terms of economy and technical reliability. This paper introduces the resource assessment procedure of tidal energy that has been applied in Korea coastal regions. The key research subjects for tidal current power together with the interaction effect of multi-arrangement is described. Also, this paper is to introduce the research output of each subject such as turbine design, experimental validation, turbine interaction and wake, multi-array module, FSI (fluid-structure interaction), and duct application.
文摘Potential revenue from wind power generation is an important factor to be considered when planning a wind power investment.In the future,that may become even more important because it is known that wind power generation tends to push electricity wholesale prices lower.Consequently,it is possible that if a region has plenty of installed wind power capacity,revenue per generated unit of electricity is lower there than could be assumed by looking at the mean electricity wholesale price.In this paper,we compare 17 different locations in Finland in terms of revenue from wind power generation.That is done by simulating hourly generation with three different turbine types at two different hub heights and multiplying that by the hourly electricity spot price for years 2018 and 2019.Estimated revenues differ greatly between locations and turbine types,major factor being technical potential i.e.,the amount of electricity generated.Differences between revenues per generated MWh seem to be small,however,the smallest figures being on the western coast where installed capacities are also the largest in Finland.
文摘Appropriate information on solar resources is very important for a variety of technological areas, such as agriculture, meteorology, forestry engineering, and water resources, particularly for an innovative technology such as solar energy. In the market entry process of an innovative technology such as solar energy, the increased and sustained deployment of this energy technology strongly depends on the economy and reliability of the solar systems installed. The economy and reliability of a system are the consequences of a well-prepared project, resulting from an accurate knowledge of the solar resource available. Therefore, knowing the potential of the solar resource accurately is not only a need but also an imperative for the larger diffusion and use of the solar energy. The existing sources of the information on radiation in MG are quite varied, both at the institutional level and in different types of publications. The publications containing this information are project reports, internal reports of institutions, and several magazines. Thus, the quality of the data varies considerably, the information presents spatial and temporal discontinuity;moreover, the instruments and the measurement units are not standardised. The general objective of this paper is to recover, to qualify, to standardize, and to make available the best information from the current existing solar resource in MG, Brazil, either in the form of isoline charts of solar radiation or a numerical database. In this paper, the procedure to elaborate the maps of daily solar radiation and insolation, along with the monthly and annual averages, is described. We present one map with the localisation of the recording stations in addition to one annual and 12 monthly contour maps. The map of the daily global solar irradiation and the annual average determined in this project show that solar radiation on the state of Minas Gerais ranges from 4.5 to 6.5 kWh/m2. The maximum values occur in the northern region of Minas Gerais, and the minimum values occur in the southeast region, where there are areas of higher altitude (Mantiqueira and Serra do Caparaó) and the rainfall is more intense, with total annual rainfall greater than 1400 mm. The North and Northeast Regions of MG, where the largest annual irradiation of 6.5 kWh/m2 occurs, are characterised by a semiarid climate with annual rainfall between 600 - 800 mm and altitudes between 400 - 600 m. The maritime tropical air mass that acts between Brazil and Africa is the main climatic factor that inhibits cloud formation and, consequently, the rainfall in this region. Finally, the map of annual insolation reveals a consistent correlation between the daily rainfall and the solar radiation annual average.
基金supported by the National Key R&D Program of China(Grant Nos.2016YFC0600107&2016YFC0600108)。
文摘The North China district has been subjected to significant research with regard to the ore-forming dynamics,processes,and quantitative forecasting of gold deposits;it accounts for the highest number of gold reserves and annual products in China.Based on the top-level design of geoscience theory and the method adopted by the National Key R&D Project(deep process and metallogenic mechanism of North China Craton(NCC)metallogenic system),this paper systematically collects and constructs the geoscience data(district,camp,and deposit scales)in four key gold districts of North China(Jiaojia-Sanshandao,Southern Zhaoping,Wulong,and Qingchengzi).The settings associated with the geological dynamics of gold deposits were quantitatively and synthetically analyzed,namely:NCC destruction,metallogenic events,genetic models,and exploration models.Three-dimensional(3D)and four-dimensional(4D)geological modeling was performed using the big data on the districts,while the district-scale 3D exploration criteria were integrated to construct a quantitative exploration model.Among them,FLAC3D modelling and the Geo Cube software(version 3.0)were used to implement the numerical simulation of the 3D geological models and the constraints of the fluid saturation parameters of the Jiaojia fault to reconstruct the 4D fault structure models of the Jiaojia fault(with a depth of 5000 m).Using Geo Cube3.0,multiple integration modules(general weights of evidence(Wof E),Boost Wof E,Fuzzy Wof E,Logistic Regression,Information Entropy,and Random Forest)and exploration criteria were integrated,while the C-V fractal classification of A,B and C targets in four districts was carried out.The research results are summarized in the following four areas:(1)Four gold districts in the study area have more than three targets(the depth is 3000 m),and the class A,B and C targets exhibit a good spatial correlation with gold bodies that are controlled by mining engineering at depths greater than 1000 m.(2)The Boost Wof E method was used to identify the target optimization in 3D spaces(at depths of 3000–5000 m)of the Jiaojia-Sanshandao,Southern Zhaoping,and Wulong districts.(3)The general Wof E method is based on the Bayesian theory in 3D space and provides robust integration and target optimization that are suitable for the Jiaojia-Sanshandao and Southern Zhaoping districts in the Jiaodong area;it can also be applied to the Wulong district in the Liaodong area using a quantitative genetic model and an exploration model.Random forest is a multi-objective integration and target optimization method for 3D spaces,and it is suitable for the complex exploration model in the Qingchengzi district of the Liaodong area.The genetic model and exploration criteria associated with the exploration model of the Qingchengzi district were constrained by the common characteristics of the gold fault structure,magmatic rock emplacement in North China,and the strata fold and interlayer detachment structure.(4)Based on the gold reserves and the 3D block unit model of the Sanshandao gold deposit in the Jiaojia-Sanshandao district,the gold contents of the 3D block units in class A and B targets of the ore concentration were estimated to be 65.5%and 25.1%,respectively.The total Au resources of the optimized targets below a depth of 3000 m were 3908 t(including 1700 t reserves),and the total Au resources of the targets at depths from 3000 to 5000 m were 936 t.The study shows that the deep gold deposits in the four gold districts of North China exhibit a strong"transport-deposition"spatial correlation with potential targets.These"transport-deposition"spatial models represent the tectonic-magmatic-hydrothermal activities of the metallogenic system associated with the NCC destruction events and indicate the Au enrichment zones.