Virtual power plant

A virtual power plant is a link-up of small, distributed power stations, like wind farms, CHP units, photovoltaic systems, small hydropower plants and biogas units, but also of loads that can be switched off, in order to form an integrated network. The plants are controlled from one central control room.

Together with Siemens, RWE Deutschland AG carried out trial operations with hydro power plants, combined heat and power units and emergency power systems in a demonstration project until the end of 2010. In the course of this pilot project, Siemens and RWE Deutschland AG demonstrated the technical and economic deployment maturity of virtual power plants and gained insights into further application options.

Since the beginning of February 2012, the electricity produced by the systems of RWE's virtual power plant is traded at the Energy Exchange (EEX) in Leipzig within the scope of the direct marketing of plants under the German Renewable Energy Sources Act (EEG). The basis for this product of RWE's Energiedienstleistungen GmbH is the amendment to the Renewable Energy Sources Act. The market premium model, which has been laid down in the Act since 1 January 2012, provides an incentive to sell electricity generated by EEG plants directly on the energy markets. One key aim of this coordinated utilization of distributed production plants – besides the economic advantages – is to make a contribution toward improving the market integration of distributed generation systems.

Virtual power plants are not only used for marketing energy quantities produced by distributed generation systems but also play a part as regards the power grids. They enable the provision of system services in the transmission network, e.g. of control power in the so-called minute reserve range, to be organised by combining emergency generating units or electrical end-use equipment. The virtual power plant aggregates the electrical output from a multitude of plants and makes this supply available to the transmission system operator. If requested, the virtual power plant controls the immediate dispatch of the connected plants, thus contributing to grid stability.