Transitions and transformers: Reducing fire-risks in urban areas

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According to the UN, nearly two-thirds of the global population are set to live in cities by 2050. Coupled with environmental concerns that are pushing trends such as digitalisation and electric vehicle uptake, energy infrastructure operators are faced with a double-sided coin. On one side is smarter, more efficient infrastructure, on the other is higher loads and increased pressure on existing power infrastructure.

As urban intensity increases and users demand more from the grid, it’s no surprise that the MIDEL Transformer Risk Report found that over 80% of professionals surveyed are concerned about transformer failure. Safety will always be a top priority, so what more can we do to protect highly-populated urban environments from the risk of fires at substations?

Dehli, India’s most populous city, which has an estimated population growth trend of 67.6% to 2035 is a case in point. Transformers are being put to the test by an influx of people and power companies must continue to operate safely under these testing conditions.  

Take CESC Limited for example, India’s oldest utility based in the Kolkata region of India. Serving approximately 3 million consumers including domestic, industrial and commercial users, CESC operates a wide range of assets in power generation and distribution. There are more than 8,000 distribution transformers in their system, the majority of which are rated between 315 and 500 KVA. In previous decades CESC needed to install dry-type transformers in densely populated areas in order to mitigate the risk of fire. However dry-types are much more expensive than oil-based transformers, and no longer represent the most cost-effective solution for managing public safety in built up areas. 

Instead CESC has opted to trial a highly fire-resistant fluids in some of their transformers: esters. With a fire point of 316 °C in comparison to mineral oil’s 170 °C, esters provide a greater level of fire safety to protect against the trend of ‘popping’ (exploding transformers), which can cause catastrophic consequences in such a highly-populated environment.

“At CESC we are working towards the future of India’s energy infrastructure – so using a synthetic ester fluid such as MIDEL 7131 is much more than just selecting a transformer coolant”, mentioned Mithun Roy, Assistant Manager at CESC Ltd. “MIDEL’s fire safety and biodegradability properties actively facilitate our mission to protect people, the environment and the transformer assets themselves.”

Trial locations include a manufacturing workshop near a school and a plastics factory in a densely-populated area.

To help supply this demand, M&I Materials has opened its ester transformer fluid manufacturing plant and state-of-the-art laboratory near Mumbai, India. The move creates a high quality, local supply chain of the company’s MIDEL ester fluids for utilities and transformer manufacturers across the country.

With a locally manufactured product, Indian utilities will have direct access to a flexible and responsive supplier, meaning less dependence on imports for this key transformer component. As a biodegradable alternative to mineral oil, the availability of MIDEL fluids across India marks another step forward in creating a sustainable electricity grid for the future.  In addition, the M&I Materials investment in local manufacturing is a clear endorsement of the Indian Government’s “Make in India” initiative.

The operation, based in Maharashtra, is the result of a new strategic alliance with ACME Synthetic Chemicals, and will help Indian utilities and OEMs to deliver safer, greener transformers and substations. Ester transformer fluids are far more environmentally friendly than the traditional mineral oil. The company has had a presence in India, providing product and technical support, for almost a decade.

Raw materials for the manufacturing of the fluids will be sourced from locally grown soybean and rapeseed crops, providing new opportunities for local farmers and their families, in addition to creating jobs at the factory. This local facility will be able to supply ester fluids to CESC and other utilities across the continent.

Many companies are in a similar boat to CESC with the older parts of their transformer fleet currently filled with mineral oil. However, the switch to esters is an easy one for many. Through the process of retrofilling, the transition to esters doesn’t have to be an instant wholesale change to a transformer fleet – utilities can prioritise the most at-risk assets whilst keeping the rest of their transformers running. In a sector where professionals value the impact of transformer failure on business continuity only behind safety and revenue, the avoidance of downtime due to retrofilling can’t be understated.

In short, there’s no doubt that the energy transition is delivering numerous benefits and with esters being fully biodegradable, there’s no reason why companies can’t enjoy a boost to their sustainability and safety while also looking after their bottom line.

Major utilities such as Torrent Power, CESC, DMRC, GETCO, Tata Power Delhi, TNEB, Reliance Infra – to name a few – have been successfully using MIDEL ester transformer fluids throughout their networks. Manufacturing MIDEL locally will mean Indian utilities benefit from a leaner, more flexible and responsive source of supply.