Cloud computing is the study of using remote servers which are hosted on the internet to deliver on-demand computing resources on pay-for-use basis rather than a local server. Due to high energy consumption in cloud computing environments, it has become the main area of research. The amount of energy consumption becomes difficult to determine in real cloud computing infrastructure. In recent years some simulation tools have been developed to analyze the energy consumption in cloud computing environments for the researchers. This paper evaluates three different popular cloud energy consumption measuring simulators: CloudSim, CloudAnalyst and GreenCloud. All of these simulators can determine energy consumption according to their ability and capacity. The comparative study indicates that in a cloud computing environment, GreenCloud simulator is better than CloudSim and CloudAnalyst due to reliable measurement of energy consumption. The significance of this comparative study is to help out the researchers who are working on energy consumption in cloud computing environments that how GreenCloud simulator make their work efficient rather than other simulators.