Thermoeconomic optimization of a dual-purpose power and desalination plant

The thermoeconomic optimization of an actual steam power plant coupled with a MSF desalination unit is reported. A global optimization of the whole sy stem is performed based on separated local optimizations of different plant units. The local optimization procedure described herein requires fewer co mputing resources and deals with simpler mathematical problems than convent ional optimization methods. On the other hand, the local optimization metho d requires a thermoeconomic model providing the exergy and economic costs o f all mass and energy flows of a plant, including those corresponding to fr esh water and electricity produced. This application can be very useful, ei ther for the plant management in order to achieve a cost-effective operatio n, and for a better plant design. In the example given, approximately 11% o f the total cost was saved according to the optimization results in the nom inal operating conditions of the plant.