It is a concept where oil is used as a coolant. The oil is heated by the object it cools and then usually passes through a cooling unit such as an oil cooler. The cooled oil flows back into the hot object to cool it continuously. Advantages: -Oil has a higher boiling point than water, so it can be used to cool items at a temperature of 100ÃÂ°C or higher. -Oil is an electrical insulator, thus it can be used inside of or in direct contact with electrical components. -Oil is already used as a lubricant, therefore it may serve in a double use arrangement.