The thesis aims to study the Enhanced Quasi Static method (EQS) , developing the already existing work. New discretization procedures are showed and a more complete mathematical formulation is presented. The possible discretizations are then tested on simple case studies and their differences and anologies are analyzed. The tool used for the numerical computations is OpenFOAM®. This implementation leads to the creation of simple solvers for the evaluation of the power that, starting from the distribution of the flux in steady state, end with the amplitude behaviour on time. The EQS method is proposed as an alternative procedure for the evaluation of the power in a nuclear reactor; it is based on the fact that amplitude depends on time and another variable relevant for the process studied..