Wind power ramping in the Bonneville Power Administration area

The wind power data in the Bonneville Power Administration (BPA) is analyzed on an hourly and ten-minute time scale. The step changes, ramp event durations and magnitude are examined over the time period of January 2007 through October 2012. The study shows an increase in the magnitude of step changes as a result of the increased installed capacity. However, the percentage with respect to the installed capacity has remained the same.