Natural Ester Oil a Sustainable Alternative Insulation Oil to Mineral Oil for Power Transformer Industries and Electric Power System


  • Amit Kumar Electrical Engineering Department, Gautam Buddha University (GBU)


Natural ester oil, mineral oil, polychlorinated biphenyls (PCBs), transformer insulation oil


Natural ester oil is an important concern for power transformer industries, commercial and electric power system to explore sustainable technology. It is most suitable alternative to mineral oil for insulation and coolant medium for electric power transformer to operate efficient. Mineral oil is paraffin and naphtha based insulating oil derived from petroleum crude oil by fractional distillation method and have been banned due to polychlorinated biphenyls (PCBs). The disadvantage was its toxic nature and the lack of biodegradability while the natural ester oil is renewable energy source, easily available and eco-friendly in nature, derived from plant, animal fats, crops, fruits and their seeds, such as soybean oil, olive oil, mustard oil, sunflower oil, palm oil, coconut oil, cottonseed oil and canola oil etc. PCBs are harmful for human tissue, many species of birds and fishes, persistent biodegradability in soil and water. This paper explores the physical, chemical and electric properties to find better natural ester oil source instead of mineral oil. The purpose of utilization natural ester oil is to save the environment from toxic, dioxin, hazards and fire. Natural ester oil is deliberated to be one of the feasible substitute for mineral oil and silicone oil due to non-toxic, not produce any dioxin and toxic hazards in environment, low explosion risk, high flash, less flammable, low sludge in transformer tank, less time take to biodegradable processing, high value of pour point, good dielectric strength breakdown voltage, long paper aging life indicates better insulation oil medium for transformer.


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