Australia’s energy transition hinges on a single figure: up to 95% variable renewable energy (VRE) penetration in the National Energy Market by 2030, according to CSIRO and AEMO modeling. Reaching that threshold, necessary for the country to hit its 43% emissions-reduction target by 2030 and net zero by 2050, requires storage technologies that can deliver reliable, multi-hour power far beyond the capabilities of lithium-ion systems.
Yet long-duration energy storage (LDES) remains a structural bottleneck. Existing solutions—pumped hydro, compressed air, advanced chemistry systems—have faced constraints around cost, scalability, permitting, or geography. For utilities balancing soaring VRE uptake with an aging coal fleet, the gap between renewable generation and round-the-clock reliability is becoming more apparent each year.
This is the context in which Allegro Energy, a Newcastle-based startup, is advancing a water-based microemulsion electrolyte for redox flow batteries and supercapacitors. While claims of transformative storage technologies are common, the company’s approach targets several of the sector’s entrenched barriers: electrolyte cost, system safety, and multi-hour duration flexibility.
Allegro’s system uses a mixture of water, oil and surfactants as the electrolyte—an unusual formulation compared to conventional vanadium redox flow batteries, whose performance is strong but whose reliance on expensive metal inputs keeps costs high. By using a water-based medium, Allegro is positioning its product for safer operation, simpler sourcing and potentially lower costs, though no commercial pricing data has been published to date.
The company reports storage durations ranging from 4 to 24 hours, placing it in the mid-range LDES category relevant for mitigating evening ramps, multi-hour wind lulls and day-ahead supply risk. If performance metrics hold at scale, this duration flexibility could support the type of VRE-dominated grid outlined in national energy forecasts.
Testing at the Edge of the Coal Era
The most consequential test of the technology is underway at Origin Energy’s Eraring Power Station, the largest coal plant in Australia. The pilot project is designed to scale from 800 kWh to 60 MWh, a significant step for an early-stage technology and an indicator of utility-level interest in diversifying beyond lithium-ion.
The Eraring deployment is strategically notable: long-duration storage is widely viewed as critical to replacing retiring coal units, but few technologies have yet demonstrated multi-MWh performance on-site at fossil assets. Success here would strengthen the case for water-based flow systems as a complement to lithium-ion in firming VRE.
Allegro Energy has drawn public and private funding, including a $1.85 million Commonwealth Industry Growth Program grant and a $17.5 million Series A round. Both provide runway to validate and scale the technology, but commercial viability—capex, opex, lifetime cost per kilowatt-hour delivered—remains unverified beyond pilot statements.
The underlying science originated at Victoria University of Wellington, with the commercial entity established in Australia in 2021. As with most early-generation LDES platforms, the transition from lab success to multi-year commercial operation will determine its real impact.
Australia’s LDES Demand Curve Is Steep
With roughly a decade to replace coal with firmed renewables, Australia’s need for economically workable LDES is sharpening. Pumped hydro remains a key pillar, but major projects—most visibly Snowy 2.0—have faced delays and cost escalations. Lithium-ion continues to expand rapidly, but its economics tilt toward 1–4 hour durations rather than the longer intervals required for deep system reliability.
In this context, Allegro’s technology functions as one of several potential puzzle pieces. Its water-based chemistry could lower system risk and cost, while duration flexibility aligns with grid needs identified by AEMO’s Integrated System Plan.
Whether it ultimately scales will depend on demonstrated performance at Eraring, competitive pricing against established chemistries, and the ability to manufacture systems at utility volume. But the company’s inclusion as a finalist in the InnovationAus 2025 Awards for Excellence underscores the growing industry attention on diversified long-duration storage solutions as Australia accelerates toward its 2030 and 2050 climate targets.
Stay updated on the latest in energy! Follow us on LinkedIn, Facebook, and X for real-time news and insights. Don’t miss out on exclusive interviews and webinars—subscribe to our YouTube channel today! Join our community and be part of the conversation shaping the future of energy.
