# The Effect of Heat Sink Properties on Solar Cell Cooling Systems
## 5 Tendency of Heat Sink Properties
The use of a copper-copper heat sink with 15 fins was the best heat sink combination in this study. Table 2 shows that the addition of fins affects the performance of solar panels. The increase in efficiency from 5 to 10 fins was 0.61%, whereas the increase in efficiency from 10 to 15 fins was 0.21%. The increase in efficiency from 5 to 10 fins was better than that from 10 to 15 fins. This difference existed because 10 fins have better air circulation than 15 fins. A narrow fin gap can reduce the air circulation of the heat sink, as shown by the simulation results of the airflow rate that occurs in the heat sink. The intensity of 1100 W/m\({}^{2}\) produces the highest temperature. With this intensity, the use of a cooling system is clearly needed. Table 3 shows efficiency changes at each intensity. The intensity will affect the temperature of the solar cell. The use of a cooling system is to maintain the efficiency change caused by temperature. After the 800 W/m\({}^{2}\) intensity, the cooling capacity is lower than the heat generated. Table 4 shows that the effect of the combination of materials affected the amount of heat transfer. The thermal conductivity, surface area, and thickness of the material affect the conduction heat transfer. Cu-Cu heat sinks have the highest heat transfer rate. At an intensity of 1100 W/m\({}^{2}\), the heat sink with the Cu-Cu material has the lowest temperature, of 53.70 \({}^{\circ}\)C. High thermal conductivity materials can accelerate the rate of heat transfer by conduction, thus reducing the temperature of the solar panels. For comparison, the use of each intensity value causes a change in solar cell performance. This change in performance occurs due to the heat generated. As shown in Table 4, the highest temperature occurs at intensity of 1100 W/m\({}^{2}\). \begin{table}
\begin{tabular}{c c c c c c c c} \hline \hline
**Variation** & **Intensity (W/m\({}^{2}\))** & **Temperature (\({}^{\circ}\)C)** & _Voc_ (V) & _Isc_ (A)_ & **Fill Factor (-)** & **Efficiency (\%)** & **Error (\%)** \\ \hline Without cooling & 1100 & 64.6 & 19.2 & 2.81 & 2.81 & 9.5 & 9.95 \\ No fin heat sink & 1100 & 61.6 & 19.4 & 2.86 & 2.86 & 10.55 & 7.62 \\
5 fin heat sink & 1100 & 57.7 & 19.5 & 3 & 3 & 11.42 & 5.07 \\
10 fin heat sink & 1100 & 55.6 & 19.6 & 3.12 & 3.12 & 12.03 & 1.72 \\
15 fin heat sink & 1100 & 54.4 & 19.7 & 3.18 & 3.18 & 12.24 & 1.75 \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Temperature and efficiency of the solar cell. \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline
**Intensity (W/m\({}^{2}\))** & **Temperature (\({}^{\circ}\)C)** & _Voc (V)_ & _Isc (A)_ & **Fill Factor (-)** & **Efficiency (\%)** & **Error (\%)** \\ \hline
400 & 32.3 & 20.7 & 1.25 & 0.69 & 12.86 & 2.38 \\
500 & 37.2 & 20.4 & 1.41 & 0.76 & 12.56 & 0.39 \\
600 & 40 & 20.4 & 1.7 & 0.71 & 12.61 & 6.17 \\
700 & 45 & 20.2 & 2.18  
Table 5 shows a change in efficiency changes at each intensity. The higher the intensity received, the higher the working temperature of the solar cell. The use of a cooling system will result in not much difference in efficiency values. The decrease in efficiency only occurred after the intensity of 1000 W/m\({}^{2}\). At an intensity of 1000 W/m\({}^{2}\), this means that the additional cooling capacity that has been given has been exceeded.