A Study of Energy Production Change according to Atmospheric Stability and Equivalent Wind Speed in the Offshore Wind Farm using CFD Program

CFD를 이용한 등가풍속 산정과 대기안정도에 따른 연안풍력단지 발전량 변화 연구

  • Ryu, Geon-Hwa (Division of Earth Environmental System, Pusan National University) ;
  • Kim, Dong-Hyeok (Institute of Environment Studies, Pusan National University) ;
  • Lee, Hwa-Woon (Division of Earth Environmental System, Pusan National University) ;
  • Park, Soon-Young (Institute of Environment Studies, Pusan National University) ;
  • Kim, Hyun-Goo (Korea Institute of Energy Research)
  • 류건화 (부산대학교 지구환경시스템학부) ;
  • 김동혁 (부산대학교 환경연구원) ;
  • 이화운 (부산대학교 지구환경시스템학부) ;
  • 박순영 (부산대학교 환경연구원) ;
  • 김현구 (한국에너지기술연구원)
  • Received : 2015.09.17
  • Accepted : 2015.12.22
  • Published : 2016.02.29


To predict annual energy production (AEP) accurately in the wind farm where located in Seongsan, Jeju Island, Equivalent wind speed (EQ) which can consider vertical wind shear well than Hub height wind speed (HB) is calculated. AEP is produced by CFD model WindSim from National wind resource map. EQ shows a tendency to be underestimated about 2.7% (0.21 m/s) than HB. The difference becomes to be large at nighttime when wind shear is large. EQ can be also affected by atmospheric stability so that is classified by wind shear exponent (${\alpha}$). AEP is increased by 11% when atmosphere becomes to be stabilized (${\alpha}$ > 0.2) than it is convective (${\alpha}$ < 0.1). However, it is found that extreme wind shear (${\alpha}$ > 0.3) is hazardous for power generation. This results represent that AEP calculated by EQ can provide improved accuracy to short-term wind power forecast and wind resource assessment.


Equivalent wind speed;Atmospheric stability;Wind shear;Wind energy;AEP;CFD


Supported by : 부산대학교


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