Stanwell Battery Energy Storage System

The Stanwell Battery Energy Storage System is a landmark $747 million clean energy project located near Rockhampton. Featuring a 300 MW / 1,200 MWh battery made up of 324 Tesla Megapack units, the project represents a major step in Stanwell’s plan to transform the Stanwell and Tarong sites into Clean Energy Hubs. Designed to provide large‑scale energy storage, fast response, and grid stability, the project relies on robust high‑voltage infrastructure to operate reliably at this scale. Insulect supported the project by supplying critical medium‑ and high‑voltage equipment to underpin safe and dependable grid connection.

Challenge

Battery energy storage systems of this size place significant demands on electrical infrastructure. The Stanwell Battery needed to manage large power flows, frequent charge and discharge cycles, and rapid responses to grid events, all while meeting strict safety and compliance requirements. Operating across multiple voltage levels added further complexity, making reliable switching, strong insulation performance, and accurate monitoring essential. Any weakness in the high‑voltage network could impact system availability, grid stability, or asset lifespan, so proven, future‑ready equipment was critical.

Solution

Insulect delivered a coordinated package of electrical infrastructure designed to support the scale and performance requirements of the project. This included 33 kV disconnectors and post insulators for the medium‑voltage network, along with 275 kV disconnectors and post insulators to support high‑voltage transmission. To improve network visibility and performance, Insulect also supplied power quality sensors and a 33 kV instrument voltage transformer, enabling accurate measurement and monitoring of grid conditions. By supplying compatible equipment across voltage levels, Insulect helped ensure seamless integration into the battery system’s broader electrical design.

Benefits

The supplied infrastructure enables safe and reliable switching, strong mechanical and electrical support, and improved insight into system performance under fast‑changing load conditions. Accurate monitoring helps operators respond quickly to disturbances while protecting critical assets. Using proven, high‑quality components reduces operational risk and supports long‑term reliability, while Insulect’s integrated approach simplified procurement and installation across the project.

Results

With Insulect’s high‑voltage equipment in place, the Stanwell Battery Energy Storage System is positioned to deliver reliable, large‑scale energy storage and fast‑response grid support for Queensland. The project strengthens system stability while supporting Stanwell’s transition toward cleaner energy and future energy hubs. This case study demonstrates Insulect’s capability to support complex, high‑capacity battery projects with dependable infrastructure solutions that perform reliably at scale.