Do you manufacture transformers with ester (biodegradable) fluid? — Transformer FAQ

Ester-based transformer fluids represent one of the most significant advances in transformer technology over the past two decades. At ETS, we have been manufacturing ester-filled transformers since 2015 and have delivered hundreds of units across the Middle East, Africa, and Europe.

Natural Ester is derived from vegetable oils (typically soybean or rapeseed). Key advantages include: fire point of 360°C (vs 170°C for mineral oil), making it classified as K-class (less flammable) under IEC 61100; full biodegradability (>97% in 28 days per OECD 301B); and the remarkable ability to absorb moisture from cellulose paper insulation — reducing paper ageing by 5–8× and dramatically extending transformer operational life.

Synthetic Ester offers similar fire safety benefits plus superior performance in extreme cold environments (-56°C pour point vs -40°C for natural ester). It is the preferred choice for arctic and sub-arctic installations.

Retrofilling — existing mineral oil transformers can be converted to ester fluid. The process involves draining mineral oil, flushing the tank and windings, verifying gasket compatibility, and refilling with ester. This is often more cost-effective than replacement and immediately improves fire safety and environmental compliance.

Ester technology is increasingly mandated by specifications in fire-sensitive environments (data centres, hospitals, urban substations), environmentally protected areas (water catchments, nature reserves), and ESG-conscious organisations seeking to reduce their environmental footprint.

Ester-based transformer fluids represent one of the most significant advances in transformer technology over the past two decades. At ETS, we have been manufacturing ester-filled transformers since 2015 and have delivered hundreds of units across the Middle East, Africa, and Europe.

Natural Ester is derived from vegetable oils (typically soybean or rapeseed). Key advantages include: fire point of 360°C (vs 170°C for mineral oil), making it classified as K-class (less flammable) under IEC 61100; full biodegradability (>97% in 28 days per OECD 301B); and the remarkable ability to absorb moisture from cellulose paper insulation — reducing paper ageing by 5–8× and dramatically extending transformer operational life.

Synthetic Ester offers similar fire safety benefits plus superior performance in extreme cold environments (-56°C pour point vs -40°C for natural ester). It is the preferred choice for arctic and sub-arctic installations.

Retrofilling — existing mineral oil transformers can be converted to ester fluid. The process involves draining mineral oil, flushing the tank and windings, verifying gasket compatibility, and refilling with ester. This is often more cost-effective than replacement and immediately improves fire safety and environmental compliance.

Ester technology is increasingly mandated by specifications in fire-sensitive environments (data centres, hospitals, urban substations), environmentally protected areas (water catchments, nature reserves), and ESG-conscious organisations seeking to reduce their environmental footprint.