Test application of a semi-objective approach to wind forecasting for wind energy applications

Abstract

This report was prepar ed as an acco un t of w o r k spo nsored by an agency of t he Uni ted States Governm en t. Neith er th e Un ited States Government nor any agency th e reo f, nor any o f th ei r em p loyees, m akes any wa rran ty, ex press or i m pli ed , or assum es any leg al lia bili ty or respo nsi bil ity for th e accuracy, comp leteness, or use fu lness of any informati o n, apparatus, p roduct , or pro cess disclose d , o r re pr ese n ts t hat its use w oul d no t i nf rin ge pr ivately owned rig ht s. Reference herein to any speci fi c co m mercia l p rod uct, pro cess , or se rvice by trade name , tr adem ark, man ufacture r, o r oth erw ise, does not necessa rily co nst it ut e o r im ply its end o rseme nt, recomme nd at io n, or favoring by t he Un ited St ates Govern me nt or any agency t hereof. Th e views and opinions of au thors ex pressed herein do no t necessa r ily state or ref lect t hose of the U n ited St ates Governm ent o r an y agen cy t hereof.

Verification of hourly forecasts of wind turbine power output

“…Semiobjective (SO) and objective (model output statistics or MOS) forecasts of ho~rly average wind speed were compared by Wegley and Formica (1983). When these two types of forecasts were verified in terms of their respective abilities to forecast MOD-2 hourly average power output, the results obtained were somewhat different from, though not inconsistent with, the previous wind speed verification by Wegley and Formica.…”

“…Early work in estimating the predictability of the wind dealt with the predictability of hourly average wind speeds for utility operations planning. This work included studies by the International Energy Agency (Bodin and Fredriksson 1981) and studies within the United States Federal Wind Energy Program (Gilhousen [1980], Wegley [1982], and Wegley and Formica [1983]).…”

“…Verification of the wind speed forecasts that have been generated for several DOE candidate WTG sites (Wegley and Formica 1983) required examination of site-to-site variability of the SPT model. For this analysis, four sites of interest were examined:…”

“…As described in Wegley and Formica (1983), the MOS and SO forecasts were 24-hr hourly average wind speed forecasts produced twice daily. The periods for which forecasts were valid were 0600-0600 GMT and 1800-1800 GMT each day.…”

“…Any further work in wind forecasting in WTG operations should only be undertaken when appropriate data in sufficient quantity have been collected specifically for such studies. In the past, the quantity and quality of existing data have been the primary limiting factor in wind forecasting for wind energy applications (Wegley and Formica 1983, Gilhousen 1980, Bodin and Fredriksson 1981. In addition, future work should concentrate upon shorter time frames and on clusters of WTGs in order to help address loadfrequency control problems that could occur when wind energy is used on a large scale.…”