The generation of electrical and thermal energy with a single equipment provides many advantages in terms of the deployment of renewable energies for satisfying both electrical and thermal energy requirements. The maximization of the generated power for this type of equipment represents several challenges posed by its non-linear characteristics and the dynamics involved. In this work an optimizing strategy based on Lyapunov theory is proposed for solving this problem in a systematic way. The convergence of the strategy is analyzed in terms of Lyapunov functions and the dynamic characteristic of the thermal behavior. Simulation results considering a PV/T panel illustrate the effectiveness of the proposed approach as well as the requirements in terms of implementation issues. This approach can be refined to consider non-linear dynamics an uncertain description of the PV/T panel.