ISSN Online: 2377-424X
ISBN Print: 978-1-56700-421-2
International Heat Transfer Conference 15
Solar PV Passive Temperature Control Using Phase Change Materials
要約
The efficiency of solar photovoltaic (PV) panels decreases when their temperature increases; which is the
unfortunate consequence of using solar panels under the hot sun. One passive way of delaying the temperature increase of such system is by using phase change materials (PCMs) placed in a cavity directly under, and in contact, with the PV panel. Using the large latent heat of fusion of the PCM, a large amount of energy can be stored under the panel at a lower temperature effectively reducing the temperature of the assembly. For this research work, a rectangular 2D system, with a cavity filled with PCM (RT25 - melting
temperature = 299.75 K) enclosed on both sides by aluminum layers is studied numerically using COMSOL
Multiphysics (finite elements). The bulk of the PCM melting within the system is dominated by natural
convection heat transfer from the front face initially, then from both sides. However, the impact of natural
convection changes as the angle of the system is varied from 0 to 90° from the vertical; at 90°, natural
convection disappears completely. Results show that for this geometry, temperatures can be maintained at a
lower value for up to 80 minutes. Although the form of the curve for the transient surface temperatures, the
average lower temperature and the duration at which the temperature is kept low all vary with the angle at
which the system is. All pointing directly to the controlling and limiting effects of natural convection within the rectangular enclosure.