In this work, a coupled optical, electrical and thermal model of a concentrated photovoltaic-thermal (CPV-T) collector with a geometrical concentration ratio of 11 is developed. To estimate the accuracy of the coupled model, this is first validated against data of known collectors in the existing literature. Results show that the model can predict the optical and thermal performance of these collectors with a deviation under 8%. The model is then used to predict the performance of a new collector design. Simulation results reveal that the collector achieves a thermal efficiency of 68% and an electrical efficiency of 14% at a direct normal irradiance of 1000 W/m2, an ambient temperature of 25 °C, an inlet water temperature of 25 °C and a mass flowrate of 0.01 kg/s. The characteristic thermal and electrical efficiency curves of the collector are also generated. Based on this CPV-T collector design, a prototype is being constructed and tests are being performed in Mexico.