International audience; Concentrator photovoltaic (CPV) systems that use silicone-on-glass Fresnel lenses as their primary optical element have reduced power output at high and low lens temperatures. We show that incorporating a nanostructured surface on the solar cell stabilizes best module performance over an extended operating temperature range. We model the optical properties of a self-organized monolayer of glass beads deposited on a polydimethylsiloxane (PDMS) encapsulated solar cell in a CPV sub-module. Our model combines transfer matrix method (TMM), rigorous coupled wave analysis (RCWA), and ray tracing to quickly and accurately simulate the system. We find the short-circuit current gain increases as the lens deviates from its designed working temperature for all bead sizes, and that 400 nm diameter beads submerged halfway into PMDS have the highest gain (up to 2.6%).