Large-diameter　monopiles　are　widely　used　as　the　foundation　to　support　offshore　wind　turbines　(OWTs)　in　shallow　coastal　waters.　The　benefits　of　small-to-medium　diameter　tapered　piles　have　been　reported　in　the　past.　The　potential　use　of　large-diameter　tapered　monopiles　installed　by　impact　driving　to　support　OWTs　is　thus　presented,　and　then　comparatively　assessed　by　numerical　analyses　in　terms　of　energy　balance　and　installation　mechanisms.　A　three-dimensional　large　deformation　finite　element　(3D-LDFE)　model　of　monopiles　driven　in　clay　was　developed　using　a　Coupled　Eulerian-Lagrangian　(CEL)　approach.　An　advanced　user-defined　hypoplasticity　clay　(HC)　model　was　employed　to　model　undrained　kaolin　clay,　featuring　nonlinear　behavior　from　small　strain　to　large　strain.　The　force-time　curve　defined　by　the　operating　data　of　a　state-of-the-art　hammer　in　the　offshore　industry　was　inputted　to　explicitly　model　impact　driving.　Better　agreement　between　the　measured　and　the　simulated　results　was　observed　to　validate　the　accuracy　of　the　numerical　model.　The　numerical　results　obtained　give　greater　confidence　to　the　future　use　of　large　diameter　tapered　monopiles　for　OWTs.