الفهرس 
Chapter 1Only 14 pages are availabe for public view
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Abstract
Over the past two decades, there has been a steadily increasing required for photovoltaic systems that since petroleum price issues in addition to the negative impact on the global environment. Photovoltaic (PV) electricity as a sustainable form of alternative solar energy draws a growing number of private and governmental sectors investments. In addition to the cost reduction target, there is currently a policy to continuously improve the productivity of photovoltaic systems in order to maintain sustainability and to improve PV systems for future generation of PV systems. Although many PV makers specified that PV modules should work probably at the preferred working standard condition (STWC) of 40º C, often PV panels work in conditions with temperatures far above STWC values, rising as high as (80 ºC). It has been noted that the performance of the PV systems has decreased significantly due to rising of working temperatures, especially the output power of the modules. Literature on this topic has demonstrated that the usage of two types of cooling, water and ambient air to extract the modules excess heat has proved to be marginally efficient. This study develops a heat extraction technique that used a recovering heat transfer system with nanofluid. A new, V-trough concentrated solar photovoltaic CPV system equipped with nanofluid-based cooling channels directly in contact with the backside of CPV is being studied in depth in the current research. Nanofluid operates as a coolant that passes over CPV ’s back to control its optimum working temperatures for the highest performance output. The coolant (Al2O3)/water nanofluids utilized was water as a base fluid mixed with various volume concentration of 1%, 2% and 3%. As a 3 %-(Al2O3)/water nanofluid circulates, the working temperature of the CPV module decreases by 16.50 ° C relative to the uncooled reference module and maintains its working temperature below 45° C throughout the experimental studies. This decrease in the working temperatures of the in addition to the presence of reflector mirrors are both highly improved CPV module overall performance. The results revealed that the daily electrical output power of the uncooled LCPV module was 1646.85 W, whereas, was 1870.55 W with (13.58%) improvement with the case of water cooling. However, cooling with 3%-Al2O3/water nanofluid, the power output of the LPVC was 2319.88 W with (24.02%) and (40.86%) enhancement compared to pure water cooling and without cooling respectively. The rise in the volume fraction ratio of Al2O3 nanoparticles remarkably decreases the operating temperature of the LCPV module and improves both electrical and thermal efficiency. The expectation is that the proposed design would facilitate the installation of photovoltaic concentrators CPV modules on a large scale and allow private individuals and even certain industries to work outside of the electricity grid.