A Review on Palm Oil-Based Nanofluids as a Future Resource for Green Transformer Insulation System

Alternative transformer oil has been investigated universally in the past years. Different types of vegetable oil have been proposed and evaluated as replacements for conventional transformer oil (mineral oil) due to increasing exploitation and depleting petroleum reserves. In response to growing concern about global environmental and sustainable issues, this article discusses the suitability of palm oil (PO) and palm oil-based nanofluids (PO-N) as alternative transformer oils. A brief discussion of environmental concerns is provided in this paper, and the detailed properties of PO are thoroughly addressed. The electrical performance (alternating current breakdown voltage and lightning impulse breakdown voltage), physical behaviour (viscosity, flash point, and fire point), tan delta, and relative permittivity of PO and PO-N are also discussed in this paper. Based on reliable data and research, it has been proven that refined, bleached, deodorised palm oil (RBDPO) has been determined to be the most promising type of PO when compared to others. Furthermore, when CuO nanoparticles are added to RBDPO with the use of CTAB surfactant, the AC breakdown voltage increases by 173.42 % compared to RBDPO without CuO. However, there is still scope for further improvement in nanofluid stability. In addition to these studies, future research should focus on other aspects such as ageing studies, partial discharge breakdown voltage, etc. PO has interesting properties that make the industry and scientific community take notice.