The Central Electricity Authority (CEA) on May 15, 2026, issued an Advisory on the use of Ester Oil as a Technological Option in Transformers, Reactors, etc.
The following has been stated:-
•The Central Electricity Authority (CEA) has advised power utilities to consider Ester Oil as an alternative insulating and cooling medium in transformers, reactors, and other electrical equipment, alongside conventional mineral oil, wherever technically feasible.
•Ester Oil is recognized for its higher fire safety, biodegradability, and environmental benefits, while both Mineral Oil and Ester Oil are permitted under applicable Indian Standards.
•Utilities adopting Ester Oil must ensure suitable transformer design, OEM certification, and compliance with relevant standards and maintenance requirements.
•In view of the current West Asia crisis and India's dependence on imported crude oil, all Central, State, and Private Transmission Utilities have been advised to use Ester Oil in at least 10% of newly procured or installed transformers and reactors of 33 kV and above.
The detailed notification is given in the document below.
[Notification No.: CEA-PS-16/13/2025-CEI DivisionI/64705/2026]
