Australia is undergoing one of the most dramatic energy transformations of any country in the world and in 2025, that transformation accelerated sharply. Coal plants are retiring, renewable capacity is scaling fast, and battery storage has moved from a supporting role to the centrepiece of the country’s grid strategy. For investors, the opportunity is significant.
The scale of what happened in 2025 is difficult to overstate. Australia’s utility-scale BESS market commissioned 11 energy storage projects totalling 1.9 GW / 4.9 GWh during the year a figure that surpasses the combined output of all storage projects commissioned between 2017 and 2024 combined. The market didn’t just grow; it effectively started over at a new baseline. In 2025, Australia surpassed the United Kingdom to become the third-largest market for utility-scale battery energy storage systems globally, behind only China and the United States. It now hosts 14 GW / 37 GWh reportedly at or nearing financial close, and the pipeline of battery projects jumped by 45 GW in just twelve months. Australia is also the first nation to surpass 1 GWh of utility battery capacity per million people, placing it far ahead of China and the United States. Policy has been a decisive driver. The Australian government’s Capacity Investment Scheme (CIS) and New South Wales’ Long-Term Energy Services Agreements (LTESAs) played a pivotal role in providing financial incentives and reducing price uncertainty for investors.
So who is deploying capital? After analysing deal activity across Australia, we identified the following companies as the most active and noteworthy renewable energy investors in 2025.
Australia`s most active BESS investors in 2025
1) Iberdrola Australia
Iberdrola is one of the world’s largest electricity companies, headquartered in Bilbao, Spain, and active across more than 40 countries with a renewables portfolio exceeding 100 GW in operation or development globally. Its Australian subsidiary, led by CEO Ross Rolfe, has become one of the most assertive foreign investors in the country’s energy storage sector, with a stated commitment to invest €1 billion in Australia through 2028, focused primarily on large-scale battery storage.
In 2025, Iberdrola made two landmark acquisitions in Australia. In October, it acquired the 270 MW / 1,080 MWh Tungkillo Battery Energy Storage Project in South Australia from RES Australia for €275 million (approximately AUD 495 million). The four-hour duration system is expected to begin operations in 2028 and will support grid stability and renewable integration in the National Electricity Market. The Tungkillo project adds to Iberdrola’s expanding Australian battery portfolio, which now totals over 5 GW and 9 GWh across 12 projects. Iberdrola also agreed to acquire 100% of the 242 MW Ararat Wind Farm in Victoria from Partners Group and OPTrust. The operational wind farm supplies the majority of its output under long-term power purchase agreements, providing immediate contracted revenue alongside Iberdrola’s growing pipeline of development assets.
2) Potentia Energy
Potentia Energy is a joint venture co-owned by Italian renewable energy giant Enel Green Power and Japan’s INPEX, operating in Australia since 2017 under its former name Enel Green Power Australia before rebranding in December 2024. The Sydney-headquartered company has positioned itself as one of the most ambitious growth stories in the Australian renewables sector. With rights secured for a development pipeline exceeding 7 GW across Australia, Potentia is targeting a substantial increase in installed capacity across wind, solar, storage and hybrid projects.
In early 2025, Potentia completed a landmark acquisition that significantly reshaped its scale. The company acquired controlling stakes in a portfolio of over 1 GW of renewable energy assets from infrastructure investor CVC DIF and superannuation fund Cbus Super, comprising approximately 700 MW of operational wind and solar projects across multiple states and the Australian Capital Territory, alongside more than 430 MW of late-stage developments including battery energy storage systems in South Australia and Queensland. The deal made Potentia one of the largest renewable energy companies in Australia and significantly expanded its capabilities across both the National Electricity Market and the Wholesale Electricity Market in Western Australia.
3) AMPYR Australia
AMPYR Australia operates under the backing of AGP Sustainable Real Assets, an independent global investor and asset manager with over 860 MW of data centre capacity under development and 13 GW of clean energy assets operating or under development globally. The company is led in Australia by CEO Alex Wonhas, a former senior executive at the Australian Energy Market Operator who led the development of its Integrated System Plan. AMPYR has set an ambitious target of delivering 6 GWh of battery storage to the Australian grid by 2030. AMPYR closed two significant BESS transactions in 2025. In February, the company acquired Shell Energy’s 50% stake in the Wellington BESS in New South Wales, taking full ownership of the combined 1,000 MWh project, comprising a 300 MW / 600 MWh first stage and a 100 MW / 400 MWh second stage. AMPYR subsequently reached financial close on the Wellington Stage 1, securing AUD 340 million in debt financing from a lender group including Commonwealth Bank, HSBC, Rabobank, Bank of China, Société Générale and United Overseas Bank. Then, in November, AMPYR acquired the Northern Battery project in South Australia from Green Gold Energy, a 270 MW, up to eight-hour duration BESS to be built on the site of the decommissioned Northern Power Station in Port Augusta. The Northern Battery will incorporate grid-forming inverter technology, enabling it to provide voltage and frequency control services independent of conventional generation sources.
4) Intera Renewables
Intera Renewables is an Australian renewable energy developer and investor focused on utility-scale projects across solar, wind, and battery storage. The company is active across multiple states and has built a reputation for advancing large-format storage projects through the development and construction stages. In 2025, Intera acquired the 250 MW / 500 MWh Limestone Coast North Battery Energy Park in South Australia from Pacific Green, a strategically located project in one of Australia’s most active renewable energy zones that will contribute to South Australia’s ambitions to maintain its position at the global frontier of grid-scale storage deployment.
5) Greenleaf Renewables
Greenleaf Renewables is an Australian renewable energy developer focused on wind, solar, and storage projects across the country’s eastern states. The company gained full ownership of the Stony Creek Wind Farm project in Queensland’s North Burnett Region in 2025. The project will host up to 27 turbines and is designed to produce clean energy for approximately 100,000 homes annually, adding to Queensland’s growing renewable energy capacity and supporting the state’s transition away from coal-fired generation.
Source: Energy-Storage.News; Energy Storage News; PV-Magazine
