The packaging materials (especially the backsheet) directly affect the performance and reliability of photovoltaic (PV) modules, especially when exposed to locations with prolonged elevated temperatures. The scope of this work is to analyse the thermal behaviour of different crystalline silicon (c-Si) PV modules manufactured with innovative packaging components capable of reducing the operating cell temperatures and in parallel, to assess their energy yield under warm outdoor climatic conditions. In particular, the outdoor evaluation was performed with different backsheet material modules installed side by side as grid-connected systems and monitored at the PV Technology Laboratory, University of Cyprus (UCY), in Cyprus. The thermal operation comparative analysis for each system, based on acquired cell temperature measurements over a three-year period, verified that backsheets can be designed in order to keep PV modules operating at cooler temperatures, in some cases, by up to 10 °C during clear sky days. Finally, the annual energy yield results showed clearly that the systems equipped with the white control and black color thermal management backsheet systematically produced the highest annual energy yield.