This work presents an integral approach to tackle energy issues in bipedal robots. It introduces three combined ideas to increase these robots' autonomy: First, the exploitation of the inherent equilibrium that should exist in the rest position of a welldesigned mechanism; then, the efficient usage of the energy to walk based on the natural limit cycle of the system; and finally, the harvest of energy based on the new idea of regenerative walking. Simulations and experimental tests show promising results of this approach, built under a delicate equilibrium between appropriate control scheme, suitable mechanical design and proper actuators choice.