Numerical wave tanks (NWTs) provide a cost efficient and accurate tool to assess the complex fluid dynamic field around wave energy converters (WECs). In recent years, high fidelity methods based on the Reynolds-averaged NavierStokes (RANS) equations are increasingly applied for this type of analysis. However, the computational cost for a RANS-based analysis of WECs is very high, compared to lower fidelity models based on e.g. potential flow (PF) theory. Nested hydrodynamic models can combine the advantages of RANS and PF solvers. Only the near flow field of the WEC is considered in the RANS solver, whereas the far field is solved using the PF model. Thus, the overall computational effort can be decreased, with respect to pure RANS models, while maintaining a high accuracy of the solution in the region local to the device. This paper presents the development towards a new, two-way coupled, nested hydrodynamic model for future application in wave energy. The proposed nested model is successfully verified and validated against theoretical and experimental data. Some limitations are found, which hamper the applicability of the method with respect to parallelised and three dimensional cases, and should be addressed as part of future work.