Thermal management of solar photovoltaic cell by using single walled carbon nanotube (SWCNT)/water : numerical simulation and sensitivity analysis

Abstract

Despite the attractiveness of Photovoltaic (PV) cells for electrification and supplying power in term of environmental criteria and fuel saving, their efficiency is relatively low and is further decreased by temperature increment, as a consequence of absorption of solar radiation. In order to prevent efficiency degradation of solar cells due to temperature increment, thermal management is suggested. Active cooling of solar cells with use of liquid flow is one of the most conventional techniques used in recent years. By use of nanofluids with improved thermophysical properties, the efficiency of this cooling approach is improvable. In this article, Single Walled Carbon Nano Tube (SWCNT)/water nanofluid is used for cooling of a PV cell by considering variations in different factors such as volume fraction of solid phase, solar radiation, ambient temperature and mass flow rate. According to the findings, use of the nanofluid can lead to improvement in performance enhancement; however, this is not significant compared with water. In cases using water and the nanofluid at 0.5% and 1% concentrations, the maximum improvement in the efficiency of the cell compared with the cell without cooing were 49.2%, 49.3 and 49.4%, respectively. In addition, sensitivity analysis was performed on the performance enhancement of the cell and it was noticed that solar radiation has the highest impact on the performance enhancement by using the applied cooling technique, followed by ambient temperature, mass flow rate of the coolants and concentration of the nanofluid, respectively. Moreover, exergy analysis is implemented on the system and it is noticed that lower ambient temperature and solar radiation are preferred in term of exergy efficiency.