In this paper we extend the energy-shaping controller design technique, which has been successfully used for single-loop excitation regulation of synchronous generators in power systems, to the exciter - governor dual configuration. As in the simpler excitation problem, the aim of the controller is to shape the total energy function via modi. cation of the energy transfer between electrical and mechanical subsystems -but in this dual scenario we also have to take into account the energy contribution of the governor control loop dynamics. Motivated by practical considerations we also present a partial state feedback version of the controller that is derived applying thoe immersion and invariance technique recently reported in the literature. Representative simulations show how the tuning parameters effectively shape the domain of attraction of the desired stable equilibrium enhancing the transient stability of the power system.