This paper presents an optimization problem for the 3-degrees-of-freedom RRR fully planar parallel manipulator (3-RRR) based on the actuator power consumption. The optimization purposes to determine the optimal link and platform masses in order to minimize the electrical energy consumed by the actuators subject to the kinematic, geometric and dynamic constraints. The Particle Swarm Optimization (PSO), increasingly being used in various engineering applications, has been considered as the optimization tool. A discrete-time PID control scheme is designed for demonstrating the energy saving by means of the mass optimization. Finally the optimization results for the eight working modes of 3-RRR have been compared to each other and given in tables. (C) 2012 Elsevier Ltd. All rights reserved.