The photovoltaic-thermal (PVT) collector system is a relatively mature technology to harvest energy from the sun and convert to electrical and thermal energy. Recent developments in this field have shown that the PVT system can yield electrical, thermal and combined PVT efficiencies of 13.8%, 54.6% and 68.4% respectively. This introduces the application of a semi-transparent PV to a photovoltaic thermal collector (PVT) system. A new design is proposed with two semi-transparent PVs (STPVs) to enhance the PVT performance. The semi-transparent PV (STPV) will replace the conventional glass cover, and hence will permit a certain percentage of solar radiation to pass through it. The performance of the new PVT configuration with double and single glazing was analysed, where in the double glazing, the STPV replaces the lower glazing. The thermal and electrical efficiencies of the new design configuration were investigated under different climatic conditions at Malaysia, Sudan and UK. The simulation results reveal that the new PVT system could achieve electrical, thermal and combined PVT efficiencies of 20.76%, 65.7% and 86.5% respectively, enhancing the electrical efficiency due to the use of two semi-transparent PV panels and thus improving the energy harvested per unit area, putting a positive step toward the application of a multilayer semi-transparent mono-crystalline silicon PV. However, the PVT glazing is more effective in locations with relatively low ambient temperature, while it is found not feasible in locations with considerably higher temperature. Moreover, the study indicates that the PVT system is not effective for sites with low solar radiation and ambient temperature.