Bengaluru: As climate concerns increasingly influence infrastructure planning worldwide, Karnataka Power Transmission Corporation Limited (KPTCL) has taken a noteworthy step towards greening its transmission network. Away from the public spotlight, the utility recently conducted a pilot project at its 110 kV substation in Gangavathi, Koppal district, replacing conventional mineral oil with biodegradable natural ester oil in a high-voltage power transformer.The experiment marks the beginning of what could become a silent green revolution in Karnataka’s electricity sector. If scaled up, the initiative could gradually reduce the transmission network’s dependence on petroleum-based transformer oils, making it cleaner, safer and more sustainable.Sources in KPTCL told TOI that for nearly a century, transformers powering Karnataka’s homes, industries and cities have largely relied on petroleum-based mineral oil. “The move is aimed at enhancing grid safety, reducing environmental risks and extending the operational life of critical transmission assets while supporting Karnataka’s broader commitment to sustainable energy infrastructure,” said a senior technical officer at KPTCL.KPTCL currently operates 3,754 transformers across substations in Karnataka. As part of its efforts to modernise infrastructure and meet rising electricity demand, the utility has identified 45 high-voltage transformers across the state, including the one at Gangavathi, for conversion from mineral oil to natural ester oil.“Rather than replacing ageing transformers and incurring huge capital expenditure, KPTCL has adopted a cost-effective approach by upgrading existing transformers that are over 15 years old with this eco-friendly initiative, thereby improving their performance and extending their service life,” the officer added.Ram Prasath Manohar, managing director, KPTCL, said: “This green initiative is expected to enhance thermal efficiency of ageing grid assets while significantly reducing environmental risks associated with petroleum-based transformer oils. Natural ester oil, derived from vegetable sources, offer several advantages over traditional mineral oil — a derivative of petroleum products. It is fully biodegradable and has higher fire point, providing for superior thermal performance and making it particularly suitable for densely populated urban areas and remote substations where operational safety is critical.”
Key Differences Between Mineral Oil and Natural Ester Oil
Energy and tourism minister KJ George said it will reduce the environmental risks associated with pollution-causing petroleum-based products.“Karnataka has been at the forefront of adopting sustainable policies that balance infrastructure modernization with environmental responsibility. By introducing biodegradable natural ester oil in its transmission network, KPTCL has demonstrated a significant technological milestone besides ensuring fire safety across critical power installations,” he added.
