Bantrel

Bantrel Lauds Edible Oil

Bantrel is continually searching for new, environmentally friendly technology and processes.

The Bantrel Electrical Group has begun recommending to our clients that edible vegetable oil, called Envirotemp FR3 or equal, be specified for all future projects where liquid filled transformers are required.

In the past, large electrical power transformers used to be filled with Polychlorinated Biphenyl (PCBs) to provide electrical insulation and cooling. PCBs have very good electrical and fire resistance properties, but these same properties make PCBs essentially chemically inert. They are now classified as "persistent organic pollutants" which bioaccumulates in animals.

In the 1970s PCBs were banned and replaced by transformer grade mineral oil, which is still specified today. These oils are much less toxic than PCBs and are, therefore, much better for the environment, however they still take considerable time to biodegrade should there be an oil spill. They also exhibit a poor fire safety record with the result that transformers filled with mineral oil must be installed outdoors away from non-fire rated buildings and equipment. In addition, extensive containment systems must be specified to capture the oil should it leak from the transformers.

Recently there has been a new class of transformer oils developed that is based on edible vegetable oil. In addition to being much more biodegradable (biodegradable index of greater than 99 vs. 25 for mineral oil per the 21 day CEC L-33 -A-93 (U) primary biodegradability test), these edible vegetable oils also have higher dielectric strength (56 kV vs. 45 kV per ASTM D877) and a much higher flash point (330 Celsius vs. 147 Celsius per ASTM D92), making transformers filled with this type of oil suitable for installation in indoor environments.

This class of oils also prolongs the life of the transformers by reducing the rate of transformer aging. Also, the vegetable grade oil eliminates the need to provide expensive secondary containment for the transformer.

This is another example of Bantrel's innovation and progress toward designing facilities with a focus on sustainability and reduced environmental risk.