# Analysis of Thermomechanical Stresses of a Photovoltaic Panel Using a Passive System of Cooling
## 4 Conclusions  
As can been seen, the aim of this study was to reduce the operational temperature in order to increase the output power and, thus, increase the life of a panel. To reach this aim, the use of fins on the back panel as a heatsink was studied. Due to this, the free movement of the materials were restricted and thermomechanical stresses appeared. The maximum stress when there are 36 fins as a heatsink is 146.11 MPa, the most critical of the analysed cases. It is noteworthy that although the use of fins as a heatsink in a photovoltaic panel can reduce significantly the operational temperature, micro cracks could \begin{table}
\begin{tabular}{c c c} \hline \hline \multicolumn{1}{c}{**Geometry**} & \multicolumn{1}{c}{**Fins**} & \multicolumn{1}{c}{**Fin Number**} \\ \hline
1 & Conventional panel & Conventional Panel \\ \hline
2 & Rectangular & 51 fins of 30 cm \(\times\) 10 cm \(\times\) 0.005 cm \\ \hline
3 & Rectangular & 14 fins of 1 m \(\times\) 10 cm \(\times\) 0.005 cm EVA 5 \(\times\) 10\({}^{-4}\) m, TEDLAR 4 \(\times\) 10\({}^{-4}\) m \\ \hline
4 & Triangle & 14 fins of 5 cm \(\times\) 5 cm \(\times\) 1 m, EVA 5 \(\times\) 10\({}^{-4}\) m, 5 \(\times\) 10\({}^{-4}\) m, TEDLAR \\  & 4 \(\times\) 10\({}^{-4}\) m \\ \hline
5 & Triangle & 14 fins of 5 cm \(\times\) 5 cm \(\times\) 1 m, TEDLAR 2 \(\times\) 10\({}^{-4}\)m, EVA 2 \(\times\) 10\({}^{-4}\)m, \\  & 2 \(\times\) 10\({}^{-4}\) m \\ \hline
6 & Triangle & 14 fins of 5 cm \(\times\) 5 cm \(\times\) 1 m, EVA 4 \(\times\) 10\({}^{-4}\), TEDLAR 5 \(\times\) 10\({}^{-4}\) m \\ \hline
7 & Triangle & 14 fins of 5 cm \(\times\) 5 cm \(\times\) 1 m, EVA 3 \(\times\) 10\({}^{-4}\) m, 3 \(\times\) 10\({}^{-4}\) m, TEDLAR \\  & 5 \(\times\) 10\({}^{-4}\) m \\ \hline
9 & Triangle & 24 fins of 1 m \(\times\) 10 cm \(\times\) 5 cm, TEDLAR 4 \(\times\) 10\({}^{-4}\) m, EVA 5 \(\times\) 10\({}^{-4}\) m, \\  & 5 \(\times\) 10\({}^{-4}\) m \\ \hline
9 & Triangle & 36 fins of 5 cm \(\times\) 5 cm \(\times\) 30 cm, EVA 2 \(\times\) 10\({}^{-4}\) m, TEDLAR 5 \(\times\) 10\({}^{-4}\) \\ \hline
10 & Triangle & 48 fins of 5 cm \(\times\) 5 cm \(\times\) 30 cm \\ \hline
11 & Triangle & 48 fins of 5 cm \(\times\) 5 cm \(\times\) 30 cm, TEDLAR 5 \(\times\) 10\({}^{-4}\) m, EVA 6 \(\times\) 10\({}^{-4}\) m, \\  & 6 \(\times\) 10\({}^{-4}\) m \\ \hline
12 & Triangle & 48 fins of 5 cm \(\times\) 5 cm \(\times\) 30 cm, TEDLAR 5 \(\times\) 10\({}^{-4}\) m, EVA 4 \(\times\) 10\({}^{-4}\) m, \\  & 4 \(\times\) 10\({}^{-4}\) m \\ \hline
13 & Triangle & 48 fins of 5 cm \(\times\) 5 cm \(\times\) 30 cm, EVA 3 \(\times\) 10\({}^{-4}\) m, 2 \(\times\) 10\({}^{-4}\) m, TEDLAR \\  & 5 \(\times\) 10\({}^{-4}\) m \\ \hline
14 & Triangle & 48 fins of 5 cm \(\times\) 5 cm \(\times\) 30 cm, TEDLAR 5 \(\times\) 10\({}^{-4}\) m, EVA 6 \(\times\) 10\({}^{-4}\) m, \\  & 6 \(\times\) 10\({}^{-4}\) m \\ \hline
15 & Triangle & 51 fins of 5 cm \(\times\) 5 cm \(\times\) 30 cm, EVA, TEDLAR 5 \(\times\) 10\({}^{-4}\) m \\ \hline
16 & Triangle & 51 fins of 5 cm \(\times\) 5 cm \(\times\) 30 cm, TEDLAR 5 \(\times\) 10\({}^{-4}\) m, EVA 2 \(\times\) 10\({}^{-4}\) m \\ \hline
17 & Triangle & 51 fins of 5 cm \(\times\) 5 cm \(\times\) 30 cm, EVA TEDLAR 5 \(\times\) 10\({}^{-4}\) m \\ \hline
18 & Triangle & 53 fins of 5 cm \(\times\) 5 cm \(\times\) 30 cm, EVA de 2 \(\times\) 10\({}^{-4}\) m, TEDLAR 5 \(\times\) 10\({}^{-4}\) \\  & & m, 28 holes \\ \hline
19 & Triangle & 54 fins of 5 cm \(\times\) 5 cm \(\times\) 30 cm, EVA 2 \(\times\) 10\({}^{-4}\) m, TEDLAR 5 \(\times\) 10\({}^{-4}\) m \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Geometries Studied. be induced because of high thermomechanical stresses and this would cause a considerable drop in the output power. To assure the effective operation of the photovoltaic panel, the recommendations mentioned in the guidelines of IEC 61215 should be taken into account, some of which are regarding monitoring the temperature coefficient and the thermal cycle.