# Computational Modeling of Passive and Active Cooling Methods to Improve PV Panels Efficiency
## 1 Introduction  
One of the great concerns in the world is the energy crisis that could occur on the planet since in most countries conventional sources are still used for power generation [1]. This situation is due to the accelerated growth of the world population and industrial progress, which has led to an increase in energy demand, causing major environmental problems because of the overexploitation of fossil fuels such as oil, coal, and gas. With this panorama, interest in renewable energy sources such as solar or wind energy has increased [2, 3].  
Photovoltaic (PV) solar energy is one of the most studied technologies today, which is based on the direct conversion of radiant energy from the sun into electrical energy to be used by consumers directly. Some main characteristics of PV solar energy are: (1) It is a clean energy source, (2) surplus energy can be exported to the grid, (3) it is modular, (4) PV panels are very durable, with a lifespan that can exceed 30 years, (5) the implementation costs have decreased in recent years, and (6) it has few maintenance costs [4].  
The development and subsequent use of PV panels for the conversion of solar energy have been a great advance in modern engineering, but despite this, there are still several challenges to reach a complete massification [5]. Among the aspects to improve is the dependence of the PV panel performance with the temperature increase of cells. The rise in photovoltaic panels operating temperature causes an almost linear reduction intheir performance. Therefore, continuous efforts are necessary to improve the panels' efficiency by controlling their temperature [6; 7]. There are two types of methods to reduce the operating temperature of solar panels, passive methods [8] and active methods [9]. In passive methods, cooling strategies that do not consume electrical energy are used [10; 11], whereas the active methods work with electrical energy [12; 13; 14; 15; 16].  
In tropical places such as the Colombian Atlantic coast, where the solar radiation is close to the solar constant, the performance of the PV panels is affected because of the high operating temperatures. In this context, this work presents the analysis and results of the computational modeling of cooling strategies to improve the efficiency of the solar panel when it is exposed to environmental conditions such as those existing on the Colombian Caribbean coast.  
In this research we analyze three cooling systems, passive, active and hybrid, that can be used to minimize the negative impacts of the increased temperature while attempting to enhance the efficiency of PV solar panels operating beyond the recommended temperature of the standard test conditions (STC). The computational simulations were developed using the COMSOL Multiphysics software [17]. The implementation of the solar panel and the thermal study were simulated considering factors such as solar irradiation, ambient temperature, heat transfer, surface-to-surface radiation, turbulent fluid flow, and wind speed. Finally, a quantitative analysis of the output power of the PV panel and a mathematical model that represents the I-V relationship were implemented in Matlab.  
This work is structured as follows: Section 2 presents the computational details of the PV panel modeling and the physical processes considered in the simulations. Section 3 shows the results obtained for the passive, active, and hybrid panels. Finally, Section 4 summarizes the main conclusions of the research.