Presentation Skills By Derreck E Jennifer Macfarlane Laura B

Presentation Skillsderreck E Jennifer Macfarlane Laura Barden Renu

Presentation skills Derreck E, Jennifer Macfarlane, Laura Barden, Renu Kumar Intro 5 Strategies TIPs Presentations & Important info Conclusion Q&A Lab Report 2 Solar Collector 4. What would happen to the efficiency if the azimuth angle of the panel is increased? The literature states that a solar collector facing south has an azimuth angle of 180 degrees, while 0 degrees when facing north. In the northern hemisphere, where we are currently located, between the latitudes of 23 and 90, the sun is always in the south. For this reason, panels are often directed to the south to get the most out of the sun’s energy.

The azimuth angle of a collector has an important effect in the efficiency of a solar collector. Different values of the Azimuth angle for a panel will play a role in increasing or decreasing its efficiency. There are a series of equations that relate the efficiency of the solar collector to the azimuth angle. This relation will help us understand how the efficiency changes with the azimuth angle. First, the efficiency Æž of a solar collector is given by Equation 1 where represents the useful heat gain, Ac the area of the collector and Ic the irradiance measured on the tilted plane of the collector.

The irradiance (Ic) measured on the tilted plane of the collector is calculated by adding the direct beam radiation (IBc) striking a collector’s face, the diffuse radiation (IDc) on the collector and the radiation (IRc) reflected by surfaces in front of the panel as seen in Equation 2 below. The direct beam radiation (IBc) is the portion of IC that accounts for the solar azimuth angle of the collector. The translation of direct-beam radiation (IB) into direct beam insolation striking a solar collector (IBc) is a function of the angle of incidence Ï´, which is located between a line drawn normal to the collector face and the incoming solar beam radiation.

The angle of incidence θ will be a function of the collector orientation and the altitude and azimuth angles of the sun at any time. Similarly, the solar collector is tipped up at an angle Ʃ and faces in a direction described by its azimuth angle φC, as shown in Figure 8 below. The incidence angle is given by Equation 3 which describes the cosine of the incidence angle (ϴ) where β represents the altitude angle, φc the collector azimuth angle, φs is the solar azimuth angle and Ʃ the tilt angle.

Similarly, the cosine of the incidence angle is used to calculate the direct-beam radiation striking the collector as shown in Equation 4. Equation 4 where IB represents the direct beam radiation. As we can see from the relations given, if we manipulate the value of the collector’s azimuth angle the angle of incidence will change and so the value for IBc. Consequently, IC will also change, and so the efficiency will vary. Now, if this angle is increased it will go through a cycle of positive and negative values.

Since cosine is periodic between 0 and 2π, it cannot increase. Therefore, if we go through the calculations, we will find out that increasing the azimuth angle can increase or decrease the value of Ic. Since Ic is in the denominator of the formula to calculate efficiency, when IC is decreased, the efficiency of the collector will increase and if IC is increased, the efficiency of the collector will decrease. Using different values in the calculation of the Azimuth angle shows that the optimal azimuth angle is with the collector facing south. Also, the array facing east would generate slightly more energy than the one facing west. Finally, if the panel is installed facing north, the energy production could be reduced up to 35%.

Paper For Above instruction

The impact of azimuth angle adjustment on solar collector efficiency is a pivotal aspect of optimizing solar energy systems. The azimuth angle, defining the compass direction that a solar panel faces, influences the amount of solar radiation that the panel receives throughout the day and consequently affects its overall efficiency. In the northern hemisphere, where the sun predominantly resides in the southern sky, panels are typically oriented towards true south (azimuth angle of about 180°) to maximize solar gain. However, variations from this optimal position can either enhance or diminish energy production, depending on the specific circumstances of installation and local solar path.

Fundamentally, the efficiency (Æž) of a solar collector can be expressed as the ratio of useful heat gain to the incident solar radiation on the collector surface. Mathematically, this is represented by the equation:

Æž = Q / (A_c × I_c)

Where Q is the useful heat gain, A_c is the collector area, and I_c is the irradiance incident on the tilted collector surface. The irradiance (I_c) alone comprises three components: direct beam radiation (I_Bc), diffuse radiation (I_Dc), and reflected radiation (I_Rc), as expressed in:

I_c = I_Bc + I_Dc + I_Rc

The direct beam component (I_Bc) is critically affected by the angle of incidence (Ï´), which depends on the collector’s orientation and the sun's position, characterized by the solar azimuth angle (φ_s) and altitude angle (β). The incidence angle θ between the incoming sunlight and the normal to the collector surface determines the amount of direct radiation striking the panel, and is calculated via the cosine law:

cos θ = sin β × cos (φ_s – φ_c) × cos Æ© + cos β × sin Æ©

This equation highlights how adjusting the azimuth angle of the collector (φ_c) influences θ, and hence the cosine of the incidence angle, directly affecting the incident direct radiation (I_Bc) and ultimately the overall irradiance (I_c). As I_c appears in the denominator of the efficiency equation, changes in irradiance will inversely affect the collector's efficiency, with reduced incident irradiance leading to higher efficiency in some cases due to decreased heat losses and vice versa.

Graphical and numerical analyses of the relationship between the azimuth angle and solar irradiance reveal that the maximum efficiency is attained when the panel faces south (azimuth of 180°). Deviating eastward or westward results in slightly less optimal energy capture, while facing north can lead to significant reductions, up to 35%, in energy output. These findings are supported by empirical studies indicating that the east-facing arrays yield marginally higher energy than west-facing ones, due to the sun's path and the angle of incidence throughout the day.

The periodic nature of the cosine function governing the incidence angle means that increasing the azimuth angle beyond the optimal south-facing position first decreases efficiency, then increases upon passing the cycle's extremities. Consequently, for most northern hemisphere applications, optimizing the azimuth close to south maximizes energy harvest. Proper tilt and orientation, along with considerations of local solar trajectories and shading factors, are crucial in system design to harness maximum solar energy efficiently.

In conclusion, the azimuth angle plays a vital role in the performance of solar collectors. Adjusting it away from the optimal south-facing position generally reduces efficiency, with the greatest reductions observed when panels face north. System designers should prioritize south-facing orientations with appropriate tilt angles to maximize energy production and reduce costs associated with oversized systems or underperforming panels. Additionally, incorporating adjustable or tracking systems can further optimize the angle of incidence throughout the year, increasing overall system efficiency and energy output.

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