This paper describes a novel type of solar concentrator - a mirror symmetrical dielectric totally internally reflecting concentrator (MSDTIRC). This new concentrator type has been designed to satisfy the following objectives: (i) to provide optimum gain in two different planes, therefore increasing the electrical output of a solar photovoltaic (PV) system, and (ii) to reduce the amount of the PV cell material needed, hence minimising the cost of the system. The concentrator is capable of having two different acceptance angles on different planes. The procedure of designing an MSDTIRC is explained and the geometrical properties are analysed in detail. In addition, the optical concentration gain is presented for various angles of incidence. Through simulation results, it is demonstrated that the MSDTIRC provides significant optical concentration gain within its acceptance angle, as high as 13.54x when compared with non-concentrating solar cell. It can be concluded that the MSDTIRC can be a way to produce a low cost solar PV system and can be chosen as an alternative design for the BIPV systems. (C) 2013 Elsevier Ltd. All rights reserved.