再生エネルギー研究センターパンフレット（英語）

9/20

8Main Research FacilitiesA prototype of nacelle mounted LIDAR manufactured by a domestic manufacturer(The photograph taken with an operation-state monitoring camera on a nacelle)It is a device that allows the measurement and assessment of wind speeds and directions on the upstream side of a wind turbine by irradiating laser light in front of a wind turbine (in nine directions).Research wind turbineKOMAIHALTEC Inc. KWT300Rated power output: 300 kW, rotor diameter: 33 m, and hub height: 41.5 mA wind turbine is designed to withstand severe external conditions in Japan (highly turbulent flow arising from the complex terrains, etc.). AIST also made cooperation and contributions through joint studies at the design stage.Ground based LIDARIt is a device that remotely measures the wind speeds at a height of 50-200 m above the ground.Satellite and meteorological data processing systemIt is a computer system for providing a storage of about 1 PB (petabyte), which stores large-scale satellite and meteorological data and processes these data.Search device for acoustic sourceIt is a measurement system that allows surveys of acoustic sources; it comprises 30 acoustic Microphone and transducers.Doppler LIDARPower supply boxActivities and Achievements①Field demonstration results of the nacelle mounted LIDAR (Fig. 1)　The team succeeded in remotely measuring the wind speed distribution in the upstream side of a wind turbine with a high-performance nacelle mounted LIDAR. The team found that wind energy could be increased by about 6% at the maximum by reducing the appearance frequency of a yaw error larger than ±10° based on the information about the wind direction in front of a wind turbine obtained with the nacelle mounted LIDAR.②Advanced assessment technique (Numerical meteorological model) (Fig. 2)　The team developed a simulation environment for improving the spatial resolution of a numerical meteorological model by using the ASTER (Advanced Spaceborne Thermal Emission and Reflection Radiometer) data obtained from the Ministry of Economy, Trade, and Industry. The team developed the high-resolution sea-surface temperature dataset of Modis-based Sea Surface Temperature (MOSST) (Shimada et al., 2015), which resulted in the significant improvement of the reproducibility of atmospheric stability near the sea surface.③Advanced assessment technology (Satellite remote sensing) (Fig. 3)　The team developed a method for sea surface wind speed retrievals with the use of a satellite-borne Synthetic Aperture Radar (SAR) in consideration of the atmospheric stability. Moreover it is clarified that relations between fetches and retrieval errors when offshore winds blow are remarkably different from those when onshore wind blow because of a land effect. Fig. 1　Histogram of the yaw error (an error in the wind 　　　　 turbine direction against the inflow wind direction)Fig. 2　Comparison between various sea surface temperature datasets and measured data (Osaka Bay)Fig. 3　The difference between a measured value on an ocean observation tower (1 km offshore) and a retrieved SAR wind speed (Hiratsuka)Water temperatureTimeyaw erroryaw error[deg](2015.1-4)Windmill diameter[×10min] ±10°60%±10° 40%AboveBelow±10°60%±10° 40%AboveBelow