One of the major challenges of computer system design is the management and conservation of energy while satisfying QoS requirements. This paper considers two methods for reducing energy consumption of the CPU and network interface card by using Dynamic Voltage Scaling (DVS) and Transmission Power Control (TPC) techniques. Moreover, energy fairness is introduced for real-time scheduling. The effectiveness of the proposed scheme is evaluated and compared to Red Task Only (RTO) and Blue When Possible algorithms (BWP) using performance metrics, such as the percentage of energy consumption, successful ratio and total successful task instances. The simulation results show the decrease of variation in energy consumption for proving the idea of fairness. In addition, the energy efficient technique for prolonging lifetime of embedded node leads to an increase in the number of successful transmission messages.