Software OPTIMAL is a fundamental tool for core reload optimization within the core design of VVER-440 reactors. The software have been developed specifically according to the needs of DUKOVANY NPP. Since its first version release in year 1994 it is being continuously developed and improved regarding the optimization algorithm itself and the user comfort.

The primary task of the core reload optimization software is minimization of the fuel cost while fulfilling all the operational (fuel cycle length, energy production) and safety (power peaking factors) restrictions.