COST & EFFICIENCY OPTIMISATION OF THE FLUORESCENT SOLAR CONCENTRATOR

The Fluorescent 1 Solar Concentrator (FSC) is a polymer plate that contains a fluorescent species and that has photovoltaic (PV) cells attached to its small sides. Light that impinges on the plate is absorbed and subsequently emitted by the fluorescent material. Part of the emitted light is subject to total internal reflection and eventually strikes on the PV cells. When a (square) FSC gets longer, both its efficiency and cost decrease. The efficiency decrease can be ascribed to increasing losses due to self-absorption and back-ground absorption. The cost decrease can be attributed to an increasing ratio of the area of the relatively cheap polymer plate to that of the expensive PV cells. These two trends combined lead to a minimum in the cost-per-unit-of-power at a certain size. In this work, we compute both cost [€/m 2 ] and power per unit area [W/m 2 ] as well as the cost-per-unit-of-power [€/W] on the basis of a simple cost model and by simulations using a ray-tracing program. We perform a parameter study and find the optimal FSC. Adopting from another study, a cost-per-unit-area ratio of the polymer plate-to-PV of 1:15, we calculate a cost-per-unit-of-power that is only 35% of that of conventional PV. We identify enhancement possibilities of the device and present the corresponding cost-per-unit-of-power reductions. Moreover, we present results of an FSC with an optimized Cholesteric Top Mirror (CTM) and show that a relative gain in efficiency of 14% is possible.