Potential of Size Reduction of Flat-Plate Solar Collectors when Applying Al<sub>2</sub>O<sub>3</sub> Nanofluid

Abstract

The source of fossil fuel is decreasing. The price increased rapidly. Population and demand of energy increased significantly over the years. Carbon pollution and global warming are becoming major issues. The best way to overcome this problem is by changing to renewable source of energy. One of it is solar thermal energy. However, a solar technology is currently still expensive, low in efficiency and takes up a lot of space. Nanofluid is recognized as a solution to overcome this problem. Due to the high thermal conductivity of nanofluids, the thermal efficiency of a solar collector can be increased and thus decreasing the size of the system. This paper analyzes the efficiency of using the Al 2 O 3 nanofluid as absorbing medium in flat-plate solar collector and estimated the potential of size reduction. When applying the same output temperature of Al 2 O 3 nanofluid as with water, it can be observed that the collectors size can be reduced up to 24% of its original size.