Correlation between wind generation output and hydro inflows

Integration of wind generation is seen as a key issue for the power system. One area of concern is the possible interaction between wind and hydro generation.

New analysis shows that:

    New Zealand wind generation appears to be seasonal - with output typically being high from October to January and low from April to July;

    there is a moderate correlation between wind generation output and national hydro inflows (i.e. a “dry period”¯ is more likely to be a “calm period”¯). This correlation holds for wind farms throughout most of New Zealand, with the exception of Taranaki and the upper North Island.

In assessments of dry-winter security, the assumed contribution of wind should be reduced by 10% to reflect these findings.

There may also be implications for the economics of wind generation.

The Meridian dataset was prepared using NIWA weather station data, available from the National Climate Database.