How to solve our looming energy storage fix? These companies are exploring high-tech solutions

When Jonathan Fievez, chief executive of Carnegie Clean Energy, had his first child he’d just finished a long stint with Australia’s national rowing team, based in Varese, Italy. It was around the time of the 2006 Kyoto Protocol and he decided, “I’ve got to do something about this climate thing”.

“Even though it wasn’t big news back in Australia, it was certainly big news in Europe,” says Fievez, who returned home and joined wave technology firm Carnegie Clean Energy. Now, Carnegie is about to embark on an ambitious project to prove its heavily patented technology can convert waves to electrons.

Jonathan Fievez is CEO of wave energy technology company Carnegie Clean Energy.
Jonathan Fievez is CEO of wave energy technology company Carnegie Clean Energy.Credit: Trevor Collens

The life of Australia’s ageing coal-fired plants is shrinking faster than expected adding to the urgency of delivering alternative energy storage systems that can store the excess renewable energy needed to power the country’s homes and industries when the wind isn’t blowing and the sun isn’t shining – a process known as “firming”.

Australia will need four times its current firming capacity by 2050, the energy market operator estimates.

Big utility-scale lithium battery storage projects are advancing rapidly and the federal government’s troubled and costly Snowy 2.0 pumped hydro scheme often grabs headlines.

But other innovative systems are also aspiring to fill the firming gap, including Carnegie’s wave tech, a graphite alloy block that glows orange at 650 degrees, vanadium flow batteries, and compressed air generators.

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Compressed air

A decade ago, engineer Curtis VanWalleghem co-founded Canadian energy innovator Hydrostor, a company specialising in storing energy as compressed air.

VanWalleghem previously worked in the nuclear and wind industry and was grappling with a long-standing problem – how to provide the longer-duration energy storage required for balancing electricity grids powered by intermittent sun, wind and, in Canada’s case, nuclear power that couldn’t easily be dialled down.

Big lithium batteries are currently the go-to storage solution for major generators. However, they typically only store about two hours of dispatchable energy. Operators also need long-duration storage that can reliably release between eight and 12 hours of power when needed.

Using compressed air to store energy isn’t a new idea. A 300-megawatt plant, whose compressors are driven by gas, has been operating in Germany for 40 years, but the Canadians patented an emission-free version that they will now build in Australia, the first of its kind here.

Their proprietary technology will light up Broken Hill, an outback mining town that relies on back-up power from ageing diesel generators which need replacing.

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NSW’s transmission monopoly Transgrid recently signed Hydrostor to build a 200 megawatt emissions-free compressed air plant called Silver City. The company’s billion-dollar generator, expected online in 2027, will have reserve capacity of 250 megawatt-hours and provide eight hours of back-up during outages.

The plant takes electricity from the grid when it’s cheap, converts it to compressed air underground, and sells it back when demand and prices are higher, using a technique that’s surprisingly simple.

Electric-powered compressors force air down a narrow underground shaft, displacing water from a subterranean cavern through a different, larger gooseneck shaft where the liquid rises to the surface. When power is needed, gravity does the work. A valve releases water in the other direction, pushing the stored compressed air back up through electricity turbines on the surface.

Hydrostor will fashion its generator from a disused section of Broken Hill’s Potosi zinc and silver mine, allowing it to build a smaller and cheaper version. “We’ve leased from Perilya [the mine’s owner] that space which allowed us to do a smaller project as our first project in Australia,” VanWalleghem said.

Backed by Goldman Sachs and a Canadian pension fund, VanWalleghem said the company was in talks to construct six or seven similar generators with 500-megawatt capacity at various sites around the country.

“We will sink shafts down 600 metres and hollow out the rock. Once you get to 500 megawatts it is probably about a quarter of the load of Sydney, or 20 per cent of the load. They’re pretty sizable plants.”

Flow batteries

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About 38 per cent of energy flowing into the national electricity market now comes from renewables, with coal generating 56 per cent and gas around 4 per cent. The Australian Energy Market Operator says it will soon face times when the grid is powered almost entirely by renewables, whose variability has implications for the system’s security and strength.

Another company wanting to smooth the load during peaks built Australia’s first commercial vanadium-flow battery earlier this year in Bungama, outside Port Pirie in South Australia.

Vanadium-flow batteries were invented at the University of New South Wales in the mid-1980s. Their main advantage over their grid-scale lithium counterparts is their longevity, large storage capacity, and ability to charge and discharge without limitation, says Michael Rutt, the regional director for UK-based Invinity Energy Systems.

Invinity’s two-megawatt-flow battery is connected to a solar farm at Yadlamalka Energy’s Spencer Energy Project. Unlike solid state lithium-ion batteries, it relies on a liquid electrolyte infused with vanadium, a relatively abundant, conductive metal that can hold electrons, has a long life cycle, and doesn’t degrade over time.

“We use a 20-foot container footprint. Multiples of those are interconnected to create an energy storage system,” Rutt said. Inside each container sit two tanks – one positive, the other negative – stacked with cell membranes through which the electrolyte circulates, charging or discharging electric current.

The system stores energy from its nearby solar network and dispatches into the grid. “These batteries can work anywhere from four to 24 hours in terms of storage duration. We’re looking at the Australian market and seeing a very bright future,” Rutt said.

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Wave energy

To successfully transition the grid, Australia needs to triple its renewable energy output by 2030 and increase it seven-fold by 2050, AEMO says in its latest Draft 2024 Integrated System Plan.

About 6 gigawatts, enough to power 540,000 homes, of extra capacity is needed each year, compared to 4 gigawatts currently being built. Many other countries face similar energy dilemmas and Europe, in particular, is keen to tap into the latent power of the oceans.

“Waves are incredibly powerful. They can lift a cruise or container ship up and down effortlessly,” Fievez said.

Carnegie has developed a 20-metre wide, hockey puck shaped, submersible buoy that hovers a few metres under the ocean’s surface. Each unit is capable of generating 1 megawatt of energy. As the wave passes, the buoy lifts and three belts attached to the seabed drive electric winches in the buoy, passing the current generated through cables back to the shore.

The minimum size of an offshore wind farm is around 300 megawatts.
The minimum size of an offshore wind farm is around 300 megawatts.Credit: Getty

Seventy patents cover various parts of the technology. A key element, designed with help from Hewlett Packard, uses an offshore device to feed data to an AI control system that predicts the wave intensity and adjusts the buoys to best extract energy.

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Unlike Australia, Fievez said, Europe is extremely receptive to wave technology.

“We will be extracting energy from waves on a large scale. It’s just a question of when.”

Jonathon Fievez, Carnegie Clean Energy

Countries such as Portugal, Spain, France, Ireland and the UK see waves as a critical alternative to solar and wind, which fade in the depths of the northern winter. Carnegie, with a market cap of just $21 million, is an ASX minnow, but it boasts former AFL commissioner and businessman Mike Fitzpatrick among multiple investors.

Australia’s key wave regions could generate around five times the country’s annual electricity needs, Fievez said. “Sadly, we’re having to go to Europe to get support to continue on.”

The EU is targeting 1 gigawatt of ocean energy deployment by 2030 and a massive 40 gigawatts by 2050 through its Offshore Renewable Energy Strategy. Carnegie has been given $8 million by European governments to deploy and test a smaller version of its system, with buoys about 8 metres wide, as part of EuroWave’s competitive Biscay Marine Energy Platform off the coast of Spain.

The minimum size of an offshore wind farm is around 300 megawatts.“It’s early days, but 100 units is a starting point for a fully commercial project for us,” he said.

“You either spend a huge amount on storage, or you find technologies to fill the gap. We will be extracting energy from waves on a large scale. It’s just a question of when.”

Thermal energy

“When heated to 653 degrees, they glow orange,” said Mark Croudace.

The deputy chief executive of Newcastle-based MGA Thermal was talking about a heavy, rectangular 20-centimetre graphite and alloy block that the company has developed to store heat.

The patented blocks can be stacked and stored in an insulated building, and heated using cheap renewable electricity when it is plentiful in the middle of the day. The heat can be extracted at a later point and converted to high-pressure steam, powering multiple manufacturing processes.

Each block is about five litres in volume, weighs just under 10 kilograms and holds about 1.5 kilowatt-hours of energy.

“The vast bulk of the energy used by industry is in the form of heat,” Croudace said.

Corporate boards are increasingly facing pressure from investors to limit their company’s ongoing contribution to the global climate crisis. The need for rapid decarbonisation and the complexity of cutting carbon emissions from industrial processes is forcing big polluters to look at alternatives.

MGA is banking on a multi-trillion-dollar market emerging between now and 2040 for clean energy in the form of heat, and says it is getting strong interest from offshore manufacturers. Some 450,000 blocks stacked in a six-storey shed would deliver 500 megawatts or energy at a cost of around $100 million, the company estimates.

Industrial processes consume far more of Australia’s energy than residential users, said Croudace, but manufacturers don’t necessarily need decarbonised electricity from the grid – they’re more interested in clean heat or high-pressure steam for making food, chemicals or processing minerals.

“In terms of levelised cost of heat, it [the block technology] is more competitive than gas, electric or hydrogen boilers,” he said.

MGA is backed by venture capital firm Main Sequence and the Australian Renewable Energy Authority. It is building a demonstration plant that will be operational mid next year to prove the company’s technology can heat, store and discharge energy at scale.

“We are looking to be an Australian deep tech, manufacturing, decarbonisation export play,” Croudace said.

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