Studies on climate change typically consider temperature and precipitation over extended periods but less so the wind. We used the Cross-Calibrated Multi-Platform (CCMP) 24-year wind fi eld data set to investigate the...Studies on climate change typically consider temperature and precipitation over extended periods but less so the wind. We used the Cross-Calibrated Multi-Platform (CCMP) 24-year wind fi eld data set to investigate the trends of wind energy over the South China Sea during 1988-2011. The results reveal a clear trend of increase in wind power density for each of three base statistics (i.e., mean, 90 th percentile and 99 th percentile) in all seasons and for annual means. The trends of wind power density showed obvious temporal and spatial variations. The magnitude of the trends was greatest in winter, intermediate in spring, and smallest in summer and autumn. A greater trend of increase was found in the northern areas of the South China Sea than in southern parts. The magnitude of the annual and seasonal trends over the South China Sea was larger in extreme high events (i.e., 90 th and 99 th percentiles) compared to the mean conditions. Sea surface temperature showed a negative correlation with the variability of wind power density over the majority of the South China Sea in all seasons and annual means, except for winter (41.7%).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
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
基金Supported by the National Natural Science Foundation of China(Nos.5171101175,41606196)the Tianjin Natural Science Foundation(No.16JCYBJC20600)+1 种基金the National Marine Renewable Energy Programs of China(No.GHME2016ZC04)the National Marine Function-Oriented Zone Planning
文摘Studies on climate change typically consider temperature and precipitation over extended periods but less so the wind. We used the Cross-Calibrated Multi-Platform (CCMP) 24-year wind fi eld data set to investigate the trends of wind energy over the South China Sea during 1988-2011. The results reveal a clear trend of increase in wind power density for each of three base statistics (i.e., mean, 90 th percentile and 99 th percentile) in all seasons and for annual means. The trends of wind power density showed obvious temporal and spatial variations. The magnitude of the trends was greatest in winter, intermediate in spring, and smallest in summer and autumn. A greater trend of increase was found in the northern areas of the South China Sea than in southern parts. The magnitude of the annual and seasonal trends over the South China Sea was larger in extreme high events (i.e., 90 th and 99 th percentiles) compared to the mean conditions. Sea surface temperature showed a negative correlation with the variability of wind power density over the majority of the South China Sea in all seasons and annual means, except for winter (41.7%).
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.
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.
