Solid-state sources have become ubiquitous is many lighting applications. For general lighting, phosphors are typically employed to produce white light from the narrowband light emitted from solid-state sources. As the optical output power from solid-state sources keeps increasing, increasingly higher luminance can be obtained, which, unfortunately, also increases the phosphor's temperature. These materials' colour conversion potential, encoded by the quantum yield, has complex dependencies with temperature. To obtain an accurate assessment of the performance of a high-luminance white light source configuration based on individual solid-state sources, it is imperative to accurately model the temperature distribution inside the phosphor material and consider the effect of temperature on the quantum yield of the phosphor. In addition, the feedback of the varying quantum yield on the generated heat inside the phosphor should also be considered. An opto-thermal framework has been previously proposed to accurately simulate the opto-thermal effects in phosphors when designing lighting systems. In this paper, this framework is applied to a novel optical configuration to investigate thermal bottlenecks and test cooling strategies to avoid them. For the specific configuration tested, using an active cooling strategy and concentrating the laser light on the phosphor region with the best thermal dissipation proved to be the best solutions.