Hourly comparative assessment of photovoltaic thermal collector subjected to nanofluid for complete year: A case study of major cities in Pakistan

Abstract

This research targets to present a case study on the annual comparative assessment of photovoltaic thermal collectors (PV/T) by using water and Ag/water nanofluid for five different cities in Pakistan. The assessment is conducted at monthly, daily, and hourly resolutions. PV/T collector is imitated through a set of energy balance based physical models which are solved numerically for two working fluids (i.e. water and Ag/water nanofluid) in a yearly simulation format (with hourly, daily, and monthly predictions) for five major cities of Pakistan (Taxila, Peshawar, Multan, Lahore, and Karachi). Detailed comparative assessment is carried out based on the performance indicators such as electrical efficiency, thermal efficiency, heat gain, and net electricity power generation. In the results section, hourly, daily, and monthly patterns of performance indicators using water and Ag/water nanofluid are reported, followed by a comparative study between the different cities having different climatic conditions. The sensitivity of nanofluid's mass flow rate and its particle concentration on the performance indicators is also reported, and the analysis of the sensitivity of the nanofluid characteristics on the pumping and the net useful power is also presented. Assessment has indicated that the overall efficiency for Taxila, Peshawar, Multan, Lahore, and Karachi cities are similar and around 66% despite having different latitude and longitudinal locations. While using silver nanofluid as a working fluid, compared to the usage of pure water as a working fluid, overall lesser efficiency is seen at around 63.80%, for selected cities.