66kV Supply Redundancy — Bowen Basin Coal Mine

Overview

An operating coal mine in the Bowen Basin was reliant on a single 66kV power feed. Any unplanned outage on that supply — whether due to a fault, maintenance, or network event — had the potential to shut down the entire operation. The mine engaged Grid Dynamics to lead the design and delivery of an additional 66kV connection to provide the supply redundancy the site needed.

The project was complex from the outset. The proposed new supply route traversed the mining leases of several different companies, requiring coordination across multiple landholders, the mining operator, and the electricity distribution network operator. Existing infrastructure along the route had deteriorated and required repair as part of the scope.

Scope of Work

Grid Dynamics served as both Subject Matter Expert and Project Manager across all phases of the project:

• Coordination with multiple mining lease holders to establish access and agreement for the new supply corridor
• Liaison with the electricity utility to establish connection requirements and manage the approval process
• Inspection and assessment of existing overhead line and underground cable infrastructure along the proposed route
• Management of infrastructure repair works to bring existing assets to a serviceable standard
• Overhead line and underground cable testing and commissioning
• Protection studies to assess the impact of the new connection on the existing network
• Protection setting modifications to ensure correct fault clearance with the new supply arrangement in place

Outcome

The project brought a second 66kV supply into service at the mine, eliminating the single point of failure that had been a key operational risk. The mine now has the ability to maintain operations — or execute a controlled shutdown — in the event that the primary supply is de-energised for any reason, whether planned or unplanned.

The project required careful stakeholder management across a large number of parties with different interests and priorities. Keeping the scope, schedule, and technical requirements aligned across that group was a central challenge that Grid Dynamics managed throughout delivery.