Containerization with Docker has become the standard for the deployment of software in recent years since it is a lightweight method to isolate applications. However, the selection of a Docker image brings different dependencies, which can introduce energy inefficiencies that are often not documented. Recent work performs a comparative study between different base images and finds certain patterns in which some images tend to be less energy efficient for certain tasks. In this thesis, we propose a methodology to find the reason behind observed energy inefficiencies in a Docker image by using tracing to study how a workload makes use of the dependencies provided by the image. We apply this methodology to test the energy efficiency of Redis when using different base images. This leads to finding and raising awareness of energy inefficiencies in some functions from musl, the C standard library implementation used by Alpine.