Nowadays, studies on energy-efficient datacenters, especially the DataCenters powered by Renewable Energy mix (DCRE), have gained great attention. DCREs are large-scale, geo-distributed, and equipped with on-site renewable energy generators. For these features, it is expensive to perform empirical evaluations of proposed algorithms and solutions on the real-world DCREs, while the state-of-the-art datacenter simulators are not applicable for DCREs. In this paper, we present CloudSimPer (CLOUD SIMulator hybrid-Powered by rEnewable eneRgy), a general-purpose simulator that comprehensively supports the simulation of DCREs. Besides the functions such as renewable energy, geo-distribution, and long-term simulation, we also design evaluation metrics and an integrated simulation case for experimental studies in the future. The main challenge of CloudSimPer lies in designing a new model and software layer upon CloudSim, to solve the complexity of traceable and comparable simulations which connect renewable energies, datacenters, workloads, regions, and schedulers. We use the term schedulers broadly, encompassing any optimization approaches on DCREs for energy saving. We prove CloudSimPer and integrated case to be valid, so that simulation results are scientifically sound, by examining the expectation and the simulation results, and comparing the simulation results with selected competitors. CloudSimPer offers simulation services to datacenter designers, datacenter administrators, and academics.