In this paper the concept of a new method for the estimation of the heat flux distribution and the total power in CSP applications is presented. This method requires appropriate analysis of the temperature evolution on a target, or directly on a receiver. A 3-D thermal conduction model with boundary conditions to take into account the convection and radiation losses has been developed. A parametric analysis was performed and we checked how the physical parameters affect the applicability of the method. Having proven numerically the potential of this method, it was experimentally implemented in the central tower CSP plant of The Cyprus Institute at PROTEAS facilities successfully. The experience gained from the numerical and experimental application of this method is discussed.