Combined-Cycle CHP stations are highly flexible energy plants, supplying simultaneously electricity and heat to connected electricity grids and disctrict heating networks. Due to the large variability of the operating conditions of different Combined-Cycle CHP stations, which becomes even wider when several such plants supply simultaneously large district heating networks, it is necessary to optimize the operation of these stations towards improving their cooperation and mutual matching in the supply network. In this manner overall fuel inventories and operating costs can be reduced, while supply reliability is improved and environmentally sound operation is guaranteed. For local electricity supply systems in particular, increased use is made of the natural gas-fired combined heat and power cycle using combined Gas-Steam Cycles. These power plants often replace older heat-only production stations which originally operated with coal or heavy fuel oil. This old equipment may be partially retained for peak-load operation or as reserve plant.

Goal of the project was to seek the optimization of the operation of the CHP station. For every anticipated operating requirement in power production and heating demand, which depend among other things on the daily and seasonal characteristics of the network, the most economical plant operation was determined, taking into consideration the currently applicable fuel costs and heat prices. Inherent requirement in this process was to also safeguard that the prescribed emission limits were fulfilled in all situations and under all operating conditions.

In the Institute of Energy Systems of the TUHH an energy management system has been developed, which can be used at any given time independently of the current power station operating condition to quantitatively guide the optimized plant operation. All decisions on operating the plant are retained by the personnel on-site.

The philosophy behind developing this software system was to make it easily adaptable to different practical applications in the Power Industry.