Wärtsilä to Deliver Australia’s Largest DC-Coupled Hybrid Battery System

Technology group Wärtsilä will deliver a large energy storage system in Australia, which will be Wärtsilä’s second DC-coupled project in the country. Significantly, this will be the largest DC-coupled hybrid battery system in the National Electricity Market (NEM), reflecting a growing trend toward hybridisation of storage assets with co-located renewable generation. Once operational, the battery energy storage system will have the capacity to power up to 120,000 homes and businesses, providing a significant boost to the country’s renewable energy ambitions. The order will be booked by Wärtsilä in Q4 2025.

DC-coupled projects represent a shift in the future of renewable energy integration. By directly coupling solar generation with battery storage through a DC/DC converter, the architecture minimises energy losses to capture solar power that would otherwise be curtailed, significantly improving project economics, system efficiency, and overall grid stability. This helps to stabilise the grid amid growing solar and wind curtailment.

The project has secured approval for its Generator Performance Standards (GPS), marking a critical milestone in integrating renewable generation and storage at scale. Securing GPS approval was crucial to ensure the successful design and approval of the innovative DC-coupled hybrid system, with Wärtsilä’s optimisation technology playing a central role. The project is supported by a 20-year service agreement.

“This project is significantly larger than our earlier DC-coupled project, underscoring the need for this type of technology in expanding at scale,” said David Hebert, Vice President of Global Sales Management, Wärtsilä Energy Storage. “It’s particularly exciting to work on the largest DC-coupled project in the country; DC-coupled technology is a breakthrough for hybrid renewable plants and a critical step towards establishing a financially viable renewable energy future. The project is a prime example of how hybrid renewable energy and storage solutions can help stabilise Australia’s grid while advancing decarbonisation goals.”

Wärtsilä’s intelligent controls and optimisation software, GEMS, will sit at the forefront of the project, managing the integration of both the energy storage system and solar assets with the grid’s connection requirements. The GEMS Hybrid Power Plant Controller (PPC) ensures coordination between the solar farm and storage system. It conducts intelligent power control and optimised energy management operations for the entire plant to meet grid requirements and response times, charge and discharge the battery appropriately, and maximise project value.

Wärtsilä is a Tier-1 leading integrator in Australia. This project will be Wärtsilä’s ninth BESS site in the country, expanding the company’s local footprint to 1.5GW / 5.5GWh of capacity. The project is expected to be operational in 2028 and will contribute directly to Australia’s net-zero by 2045 target.

Wärtsilä | https://www.wartsila.com/