Wireless sensor networks (WSNs) comprise resource-constrained (e.g., memory, processing, and energy) sensor nodes that are deployed in different areas and are able to monitor environmental conditions. Simulation has been widely used in order to evaluate the network performance. In this context, software designers need to evaluate, refine, and validate high-level models for WSN applications at early stages of development via simulation tools, in particular for WSN applications supporting energy-harvesting devices. In the present paper, we propose a model-based transformation framework that allows the modeling and simulation of a WSN system supporting energy-harvesting capabilities. In this proposal, we start from a high-level specification based on the UML/MARTE profile, which describes an energy-harvesting WSN node. Then a model-to-text (M2T) transformation allows us to generate simulation scripts for analysis purposes by focusing on energy consumption.