Accommodating High Levels of Variable Generation - NERC

Power System Operations
Std. Dev. of Wind Forecast Error
0.3
0.25
0.2
0.15
0.1
0.05
0
0 6 12 18 24
Forecast Horizon (hours)
Figure 4.1: Forecast error as a function of time horizon 88
The Alberta Electric System Operator (AESO), in conjunction with the Alberta Energy Research
Institute and the Alberta Department of Energy, initiated a wind power forecasting pilot project
in the summer of 2006 to trial three different forecasting products over the course of a year and
to determine an effective approach to wind power forecasting in Alberta. As can be seen from
the results of this study (Figure 4.2), there can be significant variations in the amplitude and
phase (i.e. timing) between the actual and the forecast wind generation output. Improvements to
short term forecasting techniques are necessary to provide the system operator with the needed
tool for the reliable operation of the system. An important conclusion of this research was
accuracy of forecasting was improved when it covered a larger geographic area. 89
While significant effort has gone into developing accurate wind plant output forecasts for realtime
dispatch and hour ahead/day-ahead operational planning purposes, a significant effort is still
needed to integrate the forecasting tools and methods into the actual operational procedures and
supporting software systems. Major software vendors are just now beginning to focus on this
emerging need.
88 Doherty, R. and O’Malley, M.J., “Establishing the role that wind generation may have in future generation
portfolios,” IEEE Transactions on Power Systems, Vol. 21, pp. 1415 – 1422, 2006.
89 http://www.aeso.ca/downloads/Work_Group_Paper_Final_(3).pdf
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