Dalvik Virtual Machine is Open Source Software and an important part of the Android OS and its better understanding and energy optimization can significantly contribute to the overall greenness of the mobile environment. With the introduction of the OSS solution, named Android Runtime (ART) an attempt of performance and energy consumption optimization was made. In this paper we investigate and compare the performance of the Dalvik virtual and ART from energy perspective. In order to answer our research questions we executed a set of benchmarks in identical experimental setup for both runtimes, while measuring the energy spent and percentage of battery discharge. The results showed that in most of the use case scenarios Ahead-Of-Time compilation process of ART is overall more energy efficient than the Just-In- Time one of Dalvik.