This study investigates the operational efficiency of a concentrated solar photovoltaic thermal flat-plate collector system equipped with heat-resistant triple-junction photovoltaic cells and two-dimensional tracking. The collector system employes linear receiver made of aluminum and copper cooling tubes. Both aluminum and copper tubes were assessed for their impact on the electrical and thermal efficiencies of the concentrated solar photovoltaic thermal system.

The study results indicated that, despite aluminum tube heat absorbers being more cost-effective and readily available in local markets, they may not be the most suitable choice for achieving optimal performance in concentrated solar photovoltaic thermal systems. The electrical to thermal energy ratio for aluminum tube absorbers was approximately 18% to 50%, while it averaged 18% to 65% for copper tubes. Copper tubes demonstrated superior heat transfer performance compared to aluminum tubes, irrespective of the maximum temperature.

However, it is important to note that copper is vulnerable to solar radiation absorption, which can lead to elevated temperatures and subsequent alterations in heat transfer properties. These changes can have an impact on the overall thermal efficiency. In contrast to copper tubes, aluminum tubes experiences a lower temperature increase when exposed to solar radiation within the concentrated solar photovoltaic thermal collector receiver. On the other hand, the electric output was slightly higher in the copper case when compared to aluminum tubes. Furthermore, the rate of water flow had a minimal impact on electrical efficiency, whereas thermal efficiency saw an improvement with an increase in flow rate.