April 24, 2012
Munich’s utility company SWM (Stadtwerke München, or Munich City Utilities) has joined with Siemens AG to operate 12 small power stations, including 6 renewables installations, as one “virtual power plant” from which SWM balances loads and sells excess generation to outside its grid area. Their aim is to improve the reliability of planning and forecasting for decentralized power generation sources.
The companies have integrated 20 megawatts of capacity from the 12 plants including 5 hydro stations, 1 wind farm, and 6 “unit-type cogenerating stations”. The technology from Siemens helps the utility make use of increases in renewable power generation that could otherwise go to waste or overload the grid.
SWM is using a Siemens “distributed energy management” system (DEMS), which is used to note weather forecasts, current electricity prices, and demand, and then plans production accordingly. The calculated deployment schedule minimizes the costs of generation and operation in the interconnected plants making up the virtual power station.
The system makes use of software in communications technologies that connect the 12 plants, including LAN, WAN, GPRS and ISDN. The technology comes largely from the Smart Grid division of Siemens’ Infrastructure and Cities group.