Improving security of power system operation applying DG production forecasting tools

The integration of renewable energy sources (RES) into the electric energy system has become an important challenge for the utilization and control of electric power systems, because of the fluctuating and intermittent behaviour of wind and solar power generation. The reliable operation of future energy supply structures with high share of distributed generation and renewable energy sources is an important and highly complex task. Supply of energy always means to find an optimal mixture of different sources. The main issues are economic effectiveness, environmental sustainability and reliability in supply. Any energy source has its own advantages and disadvantages. Over the last years the structures of electrical power supply changed noticeable. Centralistic conventional power generation is supplemented by distributed renewable energy resources. It is obvious that Germany will only meet the ambitious greenhouse gas-reduction targets - with phasing out nuclear energy at the same time - by a major increase in renewable energy usage. The pooling of large on- and offshore wind farms into clusters in the GW range will make new options feasible for an optimized integration of wind power. For this purpose, a new structure, the wind farm cluster will be introduced. All wind farms, which are directly or indirectly connected to one transmission network node, will be associated to one wind farm cluster. Major arguments against a massive penetration of RES are the intermittent generation, the poor predictability and the missing controllability. These arguments are disproved by adapting a virtual power plant (VPP) the Renewable Combi-Plant (RCP) which aggregates and controls large wind farms, PV plants, biogas fired CHP and pumped-storage hydro power plants making use of powerful RES prediction tools. Wind farm clusters are major members of the Renewable Combi-Plant, a VPP which aggregates and controls RES to face the demand at any time.