The fluctuations in wind power entering an electrical grid (Irish grid) were
analyzed and found to exhibit correlated fluctuations with a self-similar
structure, a signature of large-scale correlations in atmospheric turbulence.
The statistical structure of temporal correlations for fluctuations in
generated and forecast time series was used to quantify two types of forecast
error: a timescale error (eτ) that quantifies the deviations between
the high frequency components of the forecast and the generated time series,
and a scaling error (eζ) that quantifies the degree to which the
models fail to predict temporal correlations in the fluctuations of the
generated power. With no apriori knowledge of the forecast models, we
suggest a simple memory kernel that reduces both the timescale error
(eτ) and the scaling error (eζ)