The need for low-power embedded systems has become very significant within the microelectronics scenario in the most recent years. A power-driven methodology is mandatory during embedded systems design to meet system-level requirements while fulfilling time-to-market. The aim of this paper is to introduce accurate and efficient power metrics included in a hardware/software (HW/SW) codesign environment to guide the system-level partitioning. Power evaluation metrics have been defined to widely explore the architectural design space at high abstraction level. This is one of the first approaches that considers globally HW and SW contributions to power in a system-level design flow for control dominated embedded systems