الفهرس 
Chapter 1: IntroductionOnly 14 pages are availabe for public view
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Abstract
The increasing demand on clean electrical energy necessitates expansion in the research and development of sustainable energy sources. Solar energy offers a great resource for green energy due to its abundance. Photovoltaic panels suffer from low electrical efficiency leading to losses in the harvested energy. Thus, concentrated photovoltaics are mainly used in order to compensate the energy lost due to commercial panels low efficiency. An optical concentrator is attached to photovoltaic panel in order to increase the irradiance at the panel surface. In order to decrease costs for electrical generation in addition of using solar concentrators, tracking systems needs to be eliminated. Tracking systems requires at least one motor to rotate photovoltaic panels. Further, mechanical systems require continuous maintenance, elevating costs for electrical generation.
The aim of the presented work is to introduce tracking free solar concentrators for photovoltaic applications. The concentrator should feature maximizing effective concentration ratio, illumination uniformity and acceptance angles range with minimum concentrator area. The main issue is to minimize as possible electrical power generation costs. Concentrated photovoltaics take advantage of using concentrating optics in order to increase irradiance at photovoltaic cell to improve efficiency and decrease electricity generation cost. The complex design structures, periodic maintenance and power consumed in tracking systems motivate the development of tracking-free systems.
The thesis is divided into six chapters as follows:
Chapter 1:
This chapter present a brief introduction to thesis work, introduction work motivation, aims and objectives. Major contribution and organization of the thesis are introduced.
Chapter 2:
This chapter concludes the literature survey for the state of the art of concentrated photovoltaic design, especially low concentrated photovoltaics suitable for tracking free applications. The development in photovoltaic technology is briefly introduced. Comparison between low concentration ratio concentrators is presented. Cell efficiency as a function of concentration ratio is discussed, favoring low concentrated photovoltaics for passive cooling systems. Introduction to ray tracing used in this work is also concluded. Finally, solar light analysis including solar geometry and solar radiation quantities are briefly introduced.
Chapter 3:
This chapter starts by offering an extensive ray analysis for the concentrator chosen for tracking free applications which is the v-trough concentrator. Acceptance and rejection mechanisms for rays and concentrator geometrical and optical properties are analyzed. Effect of skew rays is investigated deeply on concentrator performance for three-dimensional concentrators. High illumination uniformity concentrator design is then achieved by applying edge ray limitation concept on 3D v-trough. For critical applications requiring very high uniformity, integrating optical diffusers with 3D v-trough is proposed. Experimental work is conducted to test concentrator performance with integrated diffuser.
Chapter 4:
Modeling and design optimization for the three-dimensional v-trough concentrator accounting for meridional and skew rays are presented. Concentrator geometrical parameters are related to optical properties for the concentrator using ray tracing to obtain empirical equations using response surface methodology. Response equations are then used to optimize concentrator performance under different constrains, including tracking free situation. Optimum designs are obtained using desirability approach technique. Optimum designs are verified using ray tracing to insure the fitting between ray tracing results and RSM prediction
Chapter 5:
This chapter aims to extend the performance of v-trough concentrator after exploring its limits in terms of concentration ratio and illumination uniformity. Proposing using multiple stacks of v-trough concentrators to tune acceptance function for concentrator. Reshaping concentrator stack is finally introduced as a solution for efficiency decrease due to shading effect.
Chapter 6:
This chapter provides a conclusion for the work presented in thesis. Recommendations for future work are also provided.