According to legal framework developed by European Commission all EU Member States shall employ 15-minute time resolution for imbalance settlement no later than 18th of December 2020 (or 1st of January 2025 in case of derogation). For intermittent energy sources that are traditionally associated with less precise generation forecasts this might result in considerable increase in imbalance costs. This presents a unique challenge for wind power station operators as there is lack of adequate forecasting tools supporting 15-minute time-resolution. The objective of this paper is to test and provide comparative analysis of alternative data interpolation methods in order to determine approach associated with the lowest mid-term imbalance costs for wind power station operators. The results of this study support wind power station operators and grid operators in transition towards 15-minute imbalance settlement period.