Control systems engineering partner for APA's Diamantina Power Station
Keeping the lights on in Mount Isa
- Location: Mount Isa, Queensland, Australia
When you’re running the only major power station in a remote grid, there’s no room for error. APA’s Diamantina Power Station (DPS), located near Mount Isa in north-west Queensland, plays a critical role in supplying power to both industry and residents in the region. Isolated from the National Electricity Market, the area relies on a localised grid – the North West Power System – meaning DPS must deliver stability, reliability and precision with every watt it generates.
But early in the plant’s life, the collapse of the original Engineering, Procurement, and Construction Management (EPCM) contract during commissioning left APA without the documentation, support or system insights needed to operate the plant with confidence. Without a stable control systems foundation, the challenges of load variability, tight modification windows, and an inflexible DCS made day-to-day operations complex and high risk.
A long-term partnership built on trust
Mipac was first engaged in 2014 to help APA bridge the gap between the delivered Siemens control system and what was needed for stable, efficient operations. What began as a role in commissioning and historian integration soon developed into a long-standing relationship. Over nearly a decade, Mipac has acted as the lead control systems engineering partner for APA DPS – becoming a trusted extension of the site’s team and a consistent source of engineering clarity in a complex environment.
Tailored solutions for a unique grid
Working in close collaboration with APA, Mipac has delivered a wide range of services – all focused on stabilising the plant, simplifying operations and improving long-term asset performance. Key areas of work include:
Unblocking system limitations
- Upgraded overloaded T3000 architecture by splitting into three systems for improved performance
- Integrated third-party PLC/SCADA systems into the existing DCS
- Wrote and implemented new standards for graphics and configuration
Boosting operational resilience
- Addressed challenges of frequency and voltage control on an isolated grid
- Designed and commissioned modifications across systems including steam range operation, cooling water bypass, fire systems and ultrafiltration
- Enhanced control diagnostics and documentation, making maintenance easier and less time-consuming
Unlocking data-driven insights
- Integrated diverse data sources into the AVEVA PI Historian, replacing manual Excel reporting
- Built dashboards and analytics tools using PI Vision and PI Analytics to support operational decisions and strategic reporting
Customising to business context
- Developed a Master Load Shed System tailored to the commercial agreements of the regional grid
- Helped APA standardise DCS/SCADA specs across their power generation group
- Supported the site’s gradual shift from gas-based to renewable energy inputs
Outcomes that matter
The results of this ongoing collaboration speak to both technical excellence and deep operational impact:
Stability
More consistent operation, reduced operator intervention and greater system resilience to load variability
Efficiency
Decreased maintenance time thanks to better diagnostics and improved control system documentation
Insight
Enhanced visibility of production and consumption data, improving fault-finding and decision-making
Trust
A high-stakes site now operates with confidence, thanks to a dependable control environment and long-term engineering support
A partner you can build on
Operating a major power asset in an isolated grid isn’t just about technology – it’s about trust, responsiveness and continuity. Over nearly ten years, Mipac has stood beside APA as a committed, adaptable and expert control systems engineering partner – one that understands the stakes and delivers practical, forward-looking solutions that work.
Whether it’s stabilising core systems, enabling better data use or preparing for a renewable future, Mipac brings the experience and clarity that mission-critical infrastructure demands.
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