Hybrid 3D Finite difference time domain-Monte Carlo ray tracing (FDTD-MCRT) algorithm has been developed to model and optimise small and large scale plasmonically-enhanced luminescent solar concentrator (pLSC) devices for photovoltaic (PV) applications. The configuration parameters (for example, dimensions, shape, and optical properties of metal nanoparticles, luminescent species, and host material) were used to characterise the probability of optical energy transfer and loss processes, as well as reflection, refraction, absorption, emission enhancement, and total internal reflection (TIR) in the pLSC. The algorithm was validated through modelling of various doping concentrations of CdSe/ZnS quantum dots (QD) and gold nano spheres (Au NS) where ∼50% enhancement in optical conversion efficiency (OCE) was observed for a plasmonic composite of 2 ppm Au NS and 0.008 wt. % QD.