Transforming Power Supply in Mining: Rio Tinto’s Innovation at Koodaideri

Transforming Power Supply in Mining: Rio Tinto’s Innovation at Koodaideri

This is a Midel Case Study. See the original article here

Project Overview

In Western Australia, Rio Tinto is developing one of the most technologically advanced iron ore mines in its portfolio. The Koodaideri mine, a key part of the company’s ‘Mine of the Future’ initiative, integrates cutting-edge mining technology alongside extensive infrastructure. This includes a new 220kV transmission line, 39 transformers rated at 33kV, 166km of railway, an airport, and essential road access to support the site’s operations.

With the high level of electrification required, traditional transformer risk management approaches needed to be reconsidered.

Challenges in Mining Power Supply

Delivering reliable power to remote mining sites comes with several challenges:

• Logistics & Accessibility: Remote locations make transportation and maintenance costly and complex.
• Space Constraints: Mining sites have limited space, and transformers traditionally require significant clearance due to fire safety regulations.
• Fire Hazards: Mineral oil, commonly used in transformers, is highly flammable. If ignited, it can cause extensive damage and major disruptions to power supply.
• Costly Safety Measures: Fire suppression systems and additional civil works can be extremely expensive and take up valuable installation space.

To mitigate these issues, Rio Tinto opted for a safer and more efficient alternative—ester-based transformer fluids.

The Solution: MIDEL 7131 Ester Fluid

For the Koodaideri project, engineers selected MIDEL 7131, a synthetic ester fluid, instead of conventional mineral oil. This innovative solution provides several advantages:

• Enhanced Fire Safety: With a fire point of 316˚C—far higher than mineral oil’s 170˚C—MIDEL 7131 significantly reduces fire risk.
• Reduced Infrastructure Requirements: The improved safety profile eliminates the need for fire walls and allows for simpler bunding.
• Environmental Benefits: As a readily biodegradable fluid, MIDEL 7131 is a more sustainable option, making it ideal for both above- and below-ground transformer installations.

Impact & Industry Adoption

By switching to ester-based transformer fluids, Rio Tinto has not only saved millions in infrastructure costs but also set a new benchmark for transformer safety and efficiency in mining projects. The company has since expanded the use of MIDEL 7131 across other sites.

Beyond this, Rio Tinto was nominated for a Safety and Health Resources Sector Award by the Government of Western Australia. The recognition came for its innovative approach to monitoring substation safety and asset reliability, including the use of on-line partial discharge (PD) screening across over 1,000 switchgear panels at 25 mining locations.

A New Era of Mining Electrification

The Koodaideri mine is a prime example of how embracing innovative transformer technology can enhance safety, reduce costs, and improve environmental sustainability. As electrification in mining continues to grow, the industry is likely to see wider adoption of ester-based fluids as the preferred choice for transformer insulation.