Applications power system designed to supply usable solar
Applications of Smart Materials in Renewable Energy Technology1 Background1.1 Distribution of Solar RadiationThe intensity of solar radiation outside of the Earth’s atmosphere depends upon the distance between the sun and the Earth, the Earth’s atmosphere reduces the insolation through reflection, absorption (by ozone, water vapor, oxygen and carbon dioxide) and scattering (caused by air molecules, dust particles or pollution). The solar irradiance (Insolation) from is the power per unit area produced by the Sun in the form of electromagnetic radiation. Irradiance may be measured in space or at the Earth’s surface after atmospheric absorption and scattering. In good weather at noon, irradiance may reach 1000W/m2 on the Earth’s surface. This value is relatively independent of the location. The maximum insolation occurs on partly cloudy, sunny days; because of solar radiation reflecting off passing clouds, insolation can peak at up to 1400W/m2 for short periods. Fig. 1.1 shows the solar irradiance in the Earth, measured in 2008 by NASA. Fig. 1.1: Solar resource map of the World. Source: United Nations Environment Programme (UNEP), NASA Surface meteorology and Solar Energy (SSE), 2008.1.2 PV-Solar SystemA photovoltaic system, also solar PV power system, is a power system designed to supply usable solar power by means of photovoltaics. It consists of an arrangement of several components, including solar panels to absorb and convert sunlight into electricity, a solar inverter to change the electric current from DC to AC, as well as mounting, cabling and other electrical accessories to set up a working system. Solar panel electricity systems, also known as solar photovoltaics (PV), capture the sun’s energy using photovoltaic cells. These cells do not need direct sunlight to work – they can still generate some electricity on a cloudy day. The cells convert the sunlight into electricity, which can be used to run household appliances and lighting. Using of a solar tracking system could be improved the system’s overall performance.1.3 Solar Tracking TechnologyThe absorption of light by a PV panel is dependent on its angular position to the sun. A PV-solar panel must be perpendicular to the sun for maximum solar absorption, which is done by using a tracking system. Multiple tracking systems exist, which vary in reliability, accuracy, cost, and other factors. Tracking system must be chosen wisely to ensure that the tracking method increases the power gained instead of decreasing it. The use of a tracking system greatly improves the power gain from solar radiation. In many systems, a cheap microprocessor such as a Programmable Interface Controller (PIC) will have the algorithm for tracking, while information is fed to a computer, for analysis purposes. Regarding to Roth et al. (2007) the microcontroller has two primary modes, clock mode and sun mode. The clock mode calculates the position of the sun and makes any modification to the algorithm based on the solar error sensors. In the sun mode, the algorithm actively positions the solar panels. If the solar intensity decreases below a set value, the clock mode is activated. This variety of modes helps in better positioning and therefore a higher gain.1.4 Smart Materials “Shape Memory Alloys”The shape-memory alloys are alloys that “remember” its original shape and that when deformed returns to their pre-deformed shape when heated. This material is a lightweight, solid-state alternative to conventional actuators such as hydraulic, pneumatic, and motor-based systems. The two main types of shape-memory alloys are copper-aluminum-nickel, and nickel-titanium NiTi alloys but SMAs can also be created by alloying zinc, copper, gold and iron. SMAs can exist in two different phases, with three different crystal structures (i.e. twinned martensite, detwinned martensite and austenite) and six possible transformations.The difference between the heating transition and the cooling transition gives rise to hysteresis where some of the mechanical energy is lost in the process. The transformation is reversible over temperature ranges determined during the formation of the material. NiTi alloys change from austenite to martensite upon cooling; Mf is the temperature at which the transition to martensite completes upon cooling. Accordingly, during heating As and Af are the temperatures at which the transformation from martensite to austenite starts and finishes. 2 Design of Solar-Panel Tracking SystemThe exclusive smart properties, one-way, two-way shape memory effects and superelasticity, exposed by SMAs offer the possibility of producing smart sun tracking mechanisms for solar panels, even PV panels. An experimental design-model of an active solar panel tracking system actuated by SMAs elements, instead of electro-mechanical devices such electrical motors, should be the research idea in this proposed research project. A model should be designed, in terms of the technical aspects of SMAs, and should be issued as a prototype, subsequently testing.A typical existing sun tracking mechanism use closed-loop system: the sensor senses the position of the sun and sends a signal to the controlling unit, which determines the amount of actuation required and sends an appropriate signal to the motor, which tilts the solar device towards the sun. Fig. 2.1 shows the conceptual diagram of a proposed sun tracking mechanism, using SMAs. Fig. 2.1: Schematic illustration of the proposed smart sun tracking mechanismIn this proposed smart sun tracking mechanism would be to keep the solar-panel always facing the sun directly from sunrise to sunset. To accomplish this, a tilting device consisting of SMA actuators would be fitted into the solar-panel assembly. This device would be activated by the sun’s heat, whenever the solar receptor gets out of alignment with the sun, causing a tilting of the solar receptor such that it is brought face to face with the sun. Once the alignment of the solar receptor with the sun is accomplished, the actuator would cease to act until the receptor again registers a misalignment with the sun to a degree detectable by the SMA device. The most important element of this sun tracker is the SMA actuator; this could be e.g. SMA-springs.3 Research Goals and AimsMain goal of this research project is improving the efficiency of the PV solar modules by tracking the PV-solar Panel with the aid of SMAs. Furthermore, an interesting research opportunity concerning the usage of SMA and its applications in RE will be amplified. 3.1 Gaza Strip and its Suitability for constructing photovoltaic systems Palestine is located within the solar belt countries and considered as one of the highest solar potential energy; the climate conditions of the Palestinian Territories are predominantly very sunny with an average solar radiation on a horizontal surface about 5.4 kWh/m2 day.Gaza Strip is 360km2 with a high-density population of about 4,118 persons/km2, so Gaza Strip represents one of the most densely populated areas in the Middle East. Therefore, the need for renewable energy sources such as solar energy becomes essential trend especially in the political situation of Gaza Strip. From previous data, it is clear that the climate of Gaza Strip is very suitable for constructing photovoltaic system, hence it is enjoy with high global radiation degree and suitable energy.3.2 Specific objectives? Generating the required electricity from renewable resources with best energy efficacy.? Provide educational benefits regarding renewable energy and its applications for students at IUG and US colleges, universities and research institutes.? Support the growth of the renewable energy industry, with the design benefits of SMAs.? These smart materials are not available Gaza anyway; on the contrary, many US research institutes are doing very interesting research in this area.4 MethodologyThe systematic, theoretical analysis of the methods applied to the research project shows understanding which method, “best practices” can be applied to this proposed research project. It has been defined as follows:1. Problem assessment: Identifying the problem going to be studied through the research.2. Research and review: Researching more references and collecting other information and literature reviews about the assessed problem, and analyzing these information to set appropriate solutions for it.3. Knowledge acquisition: Gaining experience to be capable to design the needed prototypes.4. Design and implementation: Designing the prototype, and identifying and ordering the required materials and components.5. Testing: The testing stage is important for monitoring and evaluating the progress.6. Documentation: Periodic progress reports and a final report is going to documented, to enable the coming generations to resume operating the prototype.7. Management: The head researcher is going to be responsible for every stage of the research.5 Timeframe State the broad timeframe for the action and describe any specific factor that has been taken into account.It is expected that this project and its various activities will be implemented in 12 months. No. Activity Year Q1 Q2 Q3 Q41. Field survey of existing systems X 2. Theoretical study, Studying the solar power sys. and various tracking techniques, smart materials X X 3. Definition of system needs and selecting the (solar panels, motors, controller card, smart materials, etc.) X 4. Purchase of needed materials, equipment and supplies X X 5. Building the mechanical part, installation of sensors, solar panel, electrical wiring, X X X6. Designing, implementing, programming the controller X X X7. System integration, Implementation and testing X X9. Evaluation of Results (Workshops and Seminar) X10. Progress Final Reports and publications (conference) X6 Bibliography1 Abu-Zarifa, A., Shabat M., Implementation of low cost motion controller with input of passive Sun-position Data for PV- Solar tracking in Gaza strip, Asian Journal of Engineering and Technology, Vol. 2, (5), 466-472, 2014.2 Abu-Zarifa, A., Status and Trends of Renewable Energy Development in Gaza, 3th Asian Conference on Sustainability, Energy and the Environment, The International Academic Forum IAFOR, Osaka, Japan, June 20133 Eggeler, G., et al. “Structural and functional fatigue of NiTi shape memory alloys.” Materials Science and Engineering: A 378.1 (2004): 24-33.4 Neuking, K., Abu?Zarifa, A., Youcheu?Kemtchou, S., & Eggeler, G. (2005). Polymer/NiTi?composites: Fundamental Aspects, Processing and Properties. Advanced Engineering Materials, 7(11), 1014-1023.5 Gürzenich, D., Mathur, J., Bansal, N. K., & Wagner, H. J. (1999). Cumulative energy demand for selected renewable energy technologies. 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