Best practice in the use of short-term forecasting. Results from 2 workshops organised by the Pow'Wow project

This paper was intended to be the updated version of the similar paper presented at EWEC 2007 in Milan after the second workshop had been held. However, the planned second workshop was moved after the abstract deadline to after EWEC 2008, therefore we will not repeat last year's paper, but just summarise the main findings.International audienceShort-term forecasting of wind power for about 48 hours in advance is an established technique by now. Any utility getting over a few percent wind power penetration is buying a system or a service on the market. But which system? Also, once the system is installed and running day-to-day in the control room or on the trading floor, what is the best way to use the predictions? Which pitfalls are there to be aware of, and how can one maximise the value of the short-term forecasts

Best Practice in short-term Forecasting. A users Guide

http://powwow.risoe.dk/publ/giebelkariniotakis-bestpracticeinstf_156_ewec2007fullpaper.pdfInternational audienceShort-term forecasting of wind power for about 48 hours in advance is an established technique by now. Any utility getting over a few percent wind power penetration is buying a system or a service on the market. However, once the system is installed and running day-to-day in the control room or on the trading floor, what is the best way to use the predictions? Which pitfalls are there to be aware of, and how can one maximise the value of the short-term forecasts? For this purpose, a workshop was organised in Delft in October 2006. The aim of the paper is to present the results of this study and analyse how practices are influenced by the initial choice of the prediction approach or prediction system, the level of penetration, the intended use of the forecasts, the acceptance operators may have for wind energy, the power system management tools or functions where the forecasts are used, and many more 1

Estimation of turbulence intensity using rotor effective wind speed in Lillgrund and Horns Rev-I offshore wind farms

AbstractTurbulence characteristics of the wind farm inflow have a significant impact on the energy production and the lifetime of a wind farm. The common approach is to use the meteorological mast measurements to estimate the turbulence intensity (TI) but they are not always available and the turbulence varies over the extent of the wind farm. This paper describes a method to estimate the TI at individual turbine locations by using the rotor effective wind speed calculated via high frequency turbine data.The method is applied to Lillgrund and Horns Rev-I offshore wind farms and the results are compared with TI derived from the meteorological mast, nacelle mounted anemometer on the turbines and estimation based on the standard deviation of power. The results show that the proposed TI estimation method is in the best agreement with the meteorological mast. Therefore, the rotor effective wind speed is shown to be applicable for the TI assessment in real-time wind farm calculations under different operational conditions. Furthermore, the TI in the wake is seen to follow the same trend with the estimated wake deficit which enables to quantify the turbulence in terms of the wake loss locally inside the wind farm