Solar energy is one of the renewable energy sources that has shown promising potential in addressing the world's energy needs, particularly via the solar PV (photovoltaic) technology. However, the high cost of installation is still being considered as the main obstacle to the widespread adoption of solar PV system. The use of solar concentrators is one of the solutions that could help to produce lower cost solar PV systems. One of the existing concentrator designs is known as the RADTIRC (rotationally asymmetrical dielectric totally internally reflecting concentrator) which was developed in GCU (Glasgow Caledonian University) since 2010. This paper aims at optimising the existing RADTIRC prototype by increasing its electrical output whilst keeping the cost of the system at minimum. This is achieved by adopting a better material and a different technique to fabricate the concentrator. The optimised RADTIRC prototype was fabricated from PMMA (polymethyl-methacrylate) using injection moulding. It was found that the optimised RADTIRC-PV prototype generated an opto-electronic gain of 4.48 when compared with the bare cell under STC (standard test conditions). A comparison with the old prototype showed that the optimised RADTIRC-PV prototype increased the short circuit current by 13.57% under STC. (C) 2015 Elsevier Ltd. All rights reserved.