MODULAR REPOWERING OF POWER-PLANTS WITH NOMINAL RATINGS LOWER THAN 180 MW - A RATIONAL DESIGN APPROACH AND ITS APPLICATION TO THE ITALIAN UTILITY SYSTEM

The paper describes the rationale, the technical/economical details an d the results of a study which is part of a large-scale energy conserv ation program enacted by the Italian Public Utility (ENEL), within a b roader framework of structural interventions on the national electrici ty production/transportation/utilization network. The objective of the larger, long-term plan is to increase by a significant percentage (> 5 percent) the net con version efficiency of the national system. The purpose of the present study is to ''recover'' a large number of nearl y obsolete steam power plants by converting them to a combined cycle c onfiguration. The expression ''generalized repowering'' has been used to synthetically describe this plant reconfiguration plan, and will be employed in this paper. After giving a brief description of the exist ing Italian electricity generation situation, we list some possible cr iteria for repowering and describe in detail the configurations which were considered to be feasible. Finally, the proposed options are comp aratively analyzed, and the major parameters which can be of importanc e in the actual decision-making process on the part of the Public Util ity are computed and presented in tabular form. In the conclusions we try to put the present work in the broader perspective of a large-scal e (supernational), economically sound and ecologically acceptable ener gy conservation program.