Implementation of phase change materials for thermal regulation of photovoltaic thermal systems: Comprehensive analysis of design approaches

Highlights: • Photovoltaic thermal phase change collectors examined (PVT-PCM). • Design of PVT-PCM based collectors discussed. • Electrical performance improvement ranging from 10% to 20%. • Thermal performance improvement ranging from 30% up to 70%. • Payback period of PTV-PCM systems from 4 to 15 years. This work was focused on the investigation of various photovoltaic thermal (PVT) solar collector designs incorporating phase change materials (PVT-PCM systems) as suitable material for thermal management. In general, the PCM materials utilized in such systems were analyzed along with a discussion regarding the main thermal properties. The experimental works were covered from existing literature and related to PVT-PCM systems in various climates. The results revealed the importance of a PVT-PCM collector design concerning the overall efficiency improvement of systems. Depending on the specific design, as well as on the specific working fluid (water, air, or nanofluids), the electrical efficiency improvement was usually less than 20%, while the improvement in thermal efficiency was usually up to 70%. The electrical efficiency improvement is especially sensitive to the specific PVT-PCM collector design. The economy of the PVT-PCM system was not addressed well in the existing literature as well as its environmental evaluation. The usual payback time of the PTV-PCM systems ranged from 4 to 15 years. The conducted review indicated the necessity for more intense research investigations related to improvements in collector designs (tube geometry and layout, novel absorbers, optimization of the PCM layer) and for an integral assessment of PVT-PCM collector designs, considering performance, economic and environmental evaluations.