Green Transformers

An industry analysis on what makes a green transformer eco-efficient

Green transformers is a concept which show new way to the customers who want to preserve the environment by offering a lower carbon footprint, limited pollution risk and optimised life cycle costs thanks to less maintenance. Other advantages include reduced ageing, lower noise levels, increased fire safety and reliability. To further maximise operational management and prevent faults and damages, advanced on-line monitoring systems can also be added.

“Green transformer is the concept of 3E; Eco-friendly, Efficient and Economical,” says Divyansh Kohli, Executive Director, NDL Power Limited. “The transformer offers to be eco-friendly, by minimising the carbon footprints for its consumers. For instance, the oil used in such transformers is Ester oil produced from vegetables instead of the conventional mineral oil; Easter oil has been reputed for their eco-friendly properties and also for a high flash point of up to 350 degree C.”

One of the key benefits offered by the green power transformers is the prevention of pollution through the use of ester oil instead of mineral oil. Ester oil is biodegradable and less toxic, limiting pollution risk during operation, installation and end of life.

Rajesh Doraiswamy, Jt. Managing Director, Salzer Electronics Ltd states, “We are manufacturing transformers since the last 15 years. Transformers we make are highly efficient and result very low power loss so that can be called as a green transformer.”

Sanjib Mitra, Country Head and Sr VP – Transformer Division, Electrotherm (India) Ltd states, “In conventional transformer design, the HV and LV windings are immerged in a metal tank with sufficient cooling capacity to keep the temperature inside the tank within limit. Mineral oil is used in conventional transformer design which comes from natural resources after processing of the mother earth raw materials taken from Mines. Modern technology and innovations are helping society to extract oil from various vegetable seeds which are of similar property and otherwise is a waste or remains as an extracted by products.”

He also adds, “The conventional transformers can be easily designed with vegetable oils which can be termed as Green Transformers. Natural ester oils are very well accepted solution in this regard.”

Noise reduction
Environmental benefits include reduced noise levels to limit disturbance in urban or ecologically sensitive areas. Noise level reduction above 10 dB (A) is made possible due to selection of high-performance materials and equipment, optimised design of active parts and innovative mechanical structures.

Increased safety and reliability
With a Green Power Transformer, fire safety is improved considerably, offering increased security, not only for operators but also for those in close proximity. Ester oil has a fire point above 350 degree C, more than twice as high as mineral oil. Green transformers are less flammable and reduce fire spreading.

Divyansh believes, “One who already maintain a fleet of transformer, they can also benefit from being green. Leakages of your oil, for instance – not only harms the environment, and may cause toxicity in case of PCB; but also causes the CCA of your transformer to be damaged through high moisture ingress in the tank. These are a few of many activities that one needs to understand and perform; to ensure the upkeep and reliability of your transformer assets. Our team of experts at NDL Power Limited, have been then reliability partners to our clients for past 35 years, jointly ensuring that the transformers are monitored, efficiently managed and maintenance.”

Sanjib informs, “Online monitoring system with nitrogen purging in higher rating help the transformer surroundings to get protected from any fire in most unlikely situation like electrical fault generated within the transformer. Hermetically sealed tanks design helps to protect the surroundings from any splash of oil due to uncertain temperature rise within the tank and thus contributes for green design.”

High eco-efficiency
“Eco-efficiency is majorly the designing factor of the transformers CCA. By using concepts such as amorphous cores or finer grads of CRGO, the No load and Load losses reduces significantly; saving both the ownership cost of the asset as well as the carbon-foot print from power generation. A combination of these factors co-efficiently, increase the investment cost of the transformer but on the other hand significantly reduces the cost of ownership of the asset. Regular condition monitoring, right from the stage of its factory testing to installation and commissioning is the key factor to ensure that the system is reliable and in turn efficient,” says Divyansh.

Sanjib informs, Eco-efficient transformer design includes use of ester or equivalent vegetable oils for cooling medium which has adequate dielectric property to replace mineral oil. It not only avoids use of mineral oils, but also signifies higher efficiency and lower loss design which implies reduction of T&D loss and thus leads to national savings and higher GDP. The life of transformers also increases due to less noise and low temperature rise.

Rajesh says, “The 3-phase dry type transformers are the product of technical collaboration with Trafomodern of Austria. As, transformer application is very critical in nature, the product we make is highly reliable in terms of design. I think reliability is the number one USP in design.”

Achievement in this area
Sanjib shares his views on achievement, “BIS has already stipulated low loss transformer manufacturing in India for last 3 years. More and more distribution networks are getting connected with low loss transformers while replacing the existing high loss transformers and thus line capacities are indirectly growing to handle denser network without replacing existing line conductors and connected cables.”

He further adds, “We are supplying Level 2 transformers since last 2 years after GOI has replaced level 1 standard loss to level 2 with further reduction of transformer losses. Thanks to the central Govt. for quick implementations of BIS NORMS across the length and breadth of distributions transformer industries in the country. Without such genuine step it would have remained as a wishful thinking. I strongly believe that transformers industries will be able to manufacture more and more eco-friendly transformers and GOI’s challenging ‘UDAY’ and ‘Power for ALL’ mission will be a great success as the journey for eco-efficient transformers has already started awarding the Discoms in terms of capacity utilisation and loss minimisation in a much better and efficiency manner.”

Rajesh believes “It has been six months, since we have launched this product. Our transformers are approved by GE Locomotive in USA, and this can be regarded as an achievement in terms of transformers. We should be supplying transformers to GE Locomotive in USA in upcoming six months, as we regard this as another achievement.”

Green transformer is the concept of 3E; Eco-friendly, Efficient and Economical.
Divyansh Kohli, Executive Director, NDL Power Limited

The conventional transformers can be easily designed with vegetable oils which can be termed as Green Transformers.
Sanjib Mitra, Country Head and Sr VP – Transformer Division, Electrotherm (India)

Transformers we make are highly efficient and result very low power loss so that can be called as a green transformer.
Rajesh Doraiswamy, Jt. Managing Director, Salzer Electronics