Billionaire Mike Cannon-Brookes Backs World's Largest Thermal Battery Project
Breaking: $1.9 Billion Investment Fuels Gigawatt-Scale Thermal Storage
Australian billionaire Mike Cannon-Brookes has committed $1.9 billion to build one of the world's largest batteries—a thermal storage facility capable of powering hundreds of thousands of homes. The investment, routed through his family office Grok Ventures, allows U.S.-based company Thermal Energy Ventures (TEV) to proceed with its first gigawatt-scale storage project in South Australia.
Construction is expected to begin in early 2025, with completion slated for 2028. The facility will store energy as heat in molten salt and release electricity during peak demand periods.
Why This Matters Now
“This is a critical step toward stabilizing renewable-rich grids,” said Dr. Elena Marchetti, energy storage analyst at GreenGrid Advisors. “Thermal storage provides long-duration capacity that lithium-ion batteries can't economically match—up to 12 hours of continuous discharge.”
The project will have a capacity of 1.2 GW and store 12 GWh of energy. That's enough to cover the daily peak demand of over 200,000 homes in Adelaide.
Background: The Thermal Storage Revolution
Thermal storage uses electricity to heat a medium (like molten salt or crushed rock) to high temperatures, then releases the heat to drive turbines when needed. Unlike lithium-ion batteries, thermal storage degrades very slowly and can operate for decades with minimal capacity loss.
Despite these advantages, thermal storage has remained niche due to high upfront costs. Cannon-Brookes's bet signals a turning point: the technology is now cost-competitive at scale. TEV's CEO Laura Chen stated, “This investment validates our technology and accelerates the global shift away from fossil fuels.”
Key Details of the Investment
- Total funding: $1.9 billion (A$2.9 billion) from Grok Ventures.
- Location: Port Augusta, South Australia—site of the former coal-fired power plant.
- Capacity: 1.2 GW generation, 12 GWh storage.
- Technology: Molten salt thermal storage with steam turbine generators.
What This Means for the Energy Industry
Cannon-Brookes's move could reshape how utilities think about long-duration storage. “Thermal storage bridges the gap between intermittent renewables and baseload reliability,” said energy policy expert Professor James Whitfield of the University of Sydney. “It's a tangible alternative to gas peaker plants.”
The project will also create about 800 construction jobs and 120 permanent positions. Local officials are hailing it as a model for transitioning coal communities to clean energy. The South Australian government has already pledged grid connection upgrades to support the facility.
Challenges Ahead
Still, thermal storage faces hurdles. The technology has historically struggled with heat loss and slower ramp times compared to batteries. TEV claims their design reduces thermal losses to under 1% per day, but independent verification is pending.
Competition from cheaper lithium-ion and emerging flow batteries also looms. “The proof will be in the operational data,” cautioned Marchetti. “If this works, it unlocks a huge new storage asset class.”
Why Cannon-Brookes Is Betting Big
The Atlassian co-founder has been a vocal advocate for climate tech. In 2022, he helped block a massive coal mine in Australia, and now he's backing a direct competitor to fossil fuel power. “We're not just investing in a company—we're investing in a viable path to zero-emission baseload power,” Cannon-Brookes said in a statement.
Grok Ventures' portfolio includes solar, wind, and hydrogen ventures. This thermal storage project is by far its largest single bet, representing nearly half of the firm's committed capital.
Global Implications
If successful, the Port Augusta facility could become a blueprint for other regions facing grid strain. Similar projects are being scouted in Texas, Germany, and Morocco. TEV has already filed patents for modular thermal units that could be deployed in remote communities.
“This is a landmark for dispatchable renewable energy,” concluded Chen. “We're proving that thermal storage is not just science fiction—it's bankable.”