CIS-backed big battery hits full power and passes final tests to join the grid

More than five years since it was first proposed as what would have been, at the time, Victoria’s biggest battery, the Mornington battery energy storage system (BESS) has officially reached its full nameplate capacity of 240 megawatts (MW).

The 240 MW and 480 megawatt-hour (MWh) project’s owner, Valent Energy, on Tuesday announced that the battery – which started the commissioning process nearly a year ago – has successfully completed its final hold point test and reached its full nameplate capacity.

Each hold point test is a commissioning approval mandated by the Australian Energy Market Operator (AEMO), allowing new energy assets to progress from limited operation to full commercial operations and output through a stepped process that ensures the project is safe and reliable.

“This milestone marks a major step in the journey of the project, adding valuable dispatchable energy capacity to the Victorian Transmission network,” Valent Energy said in a LinkedIn post.

The Mornington BESS was originally proposed in 2021 by developer Maoneng before Hong Kong real estate private equity firm Gaw Capital Partners acquired a majority stake in late 2022, forming the Gaw Maoneng Renewables (GMR) joint venture.

Ownership of the Mornington BESS changed hands again in 2024 when Gaw Capital Partners and BW ESS, a leading global investor in the energy storage sector and part of BW Group, pooled their resources to create Valent Energy.

The Mornington BESS was one of seven batteries and one solar PV farm that formed Valent Energy’s initial pipeline of projects.

Construction of the Mornington BESS was completed last year, a month after the project was announced as one of 16 to win an underwriting agreement in the federal government’s Capacity Investment Scheme.

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