**5.1. DIFFERENTIAL TEMPERATURE SCOPE**

The efficiency of a PV module changes in a straight line with temperature [1, 9]:

**pv = reference[1-(Temperature of cell-Temperature of reflectivity)] (3)**

An item's value is determined by the materials from which it is crafted. Valued at 0.0045°C-1 for crystalline silicon. At the reference temperature Tref, the photovoltaic (PV) efficiency of a solar cell is denoted by the symbol ref. The value of ref is 15% when temperature is 26 degrees Celsius.

In the first, the PV efficiency is maintained at a constant reference value while the cells are fed with a constant heat flow. It can be seen from the data that the module's cells are 64.9 degrees Fahrenheit hotter in the middle than at the edges. When a PV cell is heated, its efficiency drops as shown in Eq. (3). Because of the series connection between the cells, the overall efficiency of the module is always going to be the same as the efficiency of the cell in the module's centre. At 64.9 °C, the PV efficiency of a cell may be calculated using equation (3) to provide a result of 12.3 percent. The actions performed to identify cases with comparable characteristics are summarized in 3. To make up for the decrease in PV efficiency, the heat loss from the PV cells was reduced to 760.2 W m-2 in the second iteration. This procedure is continued until the desired maximum temperature is attained in the cells and PV efficiency is achieved. Within 1% of the theoretical maximum, the cell's maximum temperature reached 66.0 °C by the third repetition, and the PV efficiency reached 12.2%.

The temperature profiles of the glass, cell, and back sheet layers are shown in Figures 3-5. PV laminates have a temperature gradient of less than 1 °C throughout their width because of the low thermal resistance between their layers. Despite the fact that convection only cools the rear of the laminate half in addition to the front, the temperature difference between the glass and the Tedlar back-sheet is just 0.12 °C.

When the border cells are enclosed in a frame, their temperature drops more quickly. According to the contour plots, the blue areas are where the metal frame completely protected the glass and back sheet from the sun. Those pieces are dispersed along the PV lamination's outside edges. By examining the temperature profile of the cells as they spread across the surface of the module, you can gain understanding of the frame cooling procedure. The cells along the building's length are separated from the framework by 6 mm, while across the width, they're set back 21 mm. Figure 4 demonstrates that the proportion of cells located in the lower temperature range is greater throughout the length of the graph than it is along its width. It has been theorized that bringing the frame closer to the cells would increase their cooling efficiency.

**Tina and Abet et al. [11]** measured the average temperature of a framed PV module by taking measurements from three different points on the module's back sheet using PT100 temperature sensors. Module surface temperature was measured, and it was found to be highest in the center and lowest on the edges. Regardless of the kind of light utilized for the measurement, a difference of around 5 °C was found. The finite element analysis results reported here also show that temperatures fluctuate throughout the system. They do their calculations and comparisons depending on where on their module the temperature sensors were placed (the centre of the corner cell and the centre of the cell in the middle of the module). A difference of 5.5 °C was computed using finite elements, which is quite similar to the value found in the experiment.

**5.2. CONVECTIVE LOSS COEFFICIENTS AND THEIR EFFECT ON TEMPERATURE AND PV CELL OUTPUT**

It is generally accepted that convection is the most unreliable means of heat dissipation in operating machinery. In order to evaluate how the convective coefficient changes with module length when subjected to forced convection, we employ the finding from Mitchell . It may also be expressed as

**h = (8.6 v 0.6) / L 0.4 (4)**

The front convective coefficient for a 2 m PV module at 1 m s-1 wind speed is determined to be 6.52 W m-2 K-1. The front convective coefficient for two parallel PV modules of the same length and wind speed is 4.94 W m-2 K-1. We assume that the convective loss coefficient at the back of the module is around 50% less than it is at the front under the identical circumstances. The results are summarized in 4. The effective convective loss coefficient is controlled by the length of the array, which in turn affects the temperature and, by extension, the efficiency of a PV system. In terms of PV efficiency, the difference is 0.22%.