<div>By implementing a solution based on wireless sensor networks one of the main aspects taken into account is the system’s energy use, so in the design phase covers various methods that seek to balance the benefits of the network with its energy consumption against the target system. This article describes on a qualitative level, routing protocols based on the hierarchical network structure, to find that balance, where the protocols are intended to improve the operation, processing and transmission of information algorithms, likewise seeks to provide a simplified overview of progress in this aspect that is now widely studied due to the rise of this technology. Its should be noted that there are other methods for saving energy and increasing the life time of such networks, methods that are mentioned but not addressed in this paper, which include the design and implementation of ultra-low power electronics, the use of long life batteries and use of new technologies on energy generation.</div>