Ecofys was assigned to perform the update of the All Island Grid Study in order to include a detailed cost benefit analysis focused on the impacts of Demand Side Management (DSM) measures in the context of 2020 scenarios with high penetrations of renewable energies in Ireland. The study included the detailed analysis of the operation of the Irish power system including energy saving actions and load flexibility (peak shifting and peak clipping) with the potential to support the integration of variable renewable energy sources.