Ellen Phiddian
Cosmos science journalist
The South Australian state government is on the brink of announcing how a colossal hydrogen electrolyser at Whyalla is to be developed.
At 250MW, it might become the biggest in the world – although in a rapidly expanding field like green hydrogen energy, this title changes frequently.
The largest currently operating electrolyser in Australia is 1.25MW, at Hydrogen Park SA.
The Whyalla electrolyser is part of the $593 million hydrogen power station being developed by the state government in the regional steel city, which also includes a 200MW hydrogen power plant and hydrogen storage.
It’s due to be operational by December 2025.
The state government launched a tender for partners to develop the power station in December 2022, and has been assessing the applicants since March.
“It’s big by world standards,” says Professor Gus Nathan, director of The University of Adelaide’s Centre for Energy Technology.
“There’s a number that are either under construction or in the process of being of being commissioned, which will be similar scale or bigger than the one that the South Australian Government is building – because we’re in a stage where basically, there’s rapid upscaling.”
Green hydrogen can be used to store and transport renewable energy. The most common way to make it is by electrolysis: splitting water (H2O) into hydrogen and oxygen, using renewable energy like solar or wind. The hydrogen can then be burned and turned back into water, releasing electricity, when needed.
“Electrolysis technology itself is not new, it’s old. It’s been around since the 40s,” says Nathan.
“But it hasn’t been very much used, because it’s still currently expensive.”
For now, green hydrogen is significantly more expensive per unit of energy generated than fossil fuels.
“But obviously, the expectation is that costs are coming down,” says Nathan.
“The point is that new research is needed to allow the hydrogen to become cost competitive or cheaper than fossil fuel.”
Nathan is part of a new research centre – the Global Hydrogen Production Technologies, or HyPT, Centre – which aims to lower the cost of large-scale hydrogen production.
“That’s really around accelerating the next generation of technology, which will then aim to meet the US target, which is which is $1 per kilogram,” says Nathan. This would make it cheaper than fossil fuel-based natural gas.
“As technology evolves, that would bring in more of the larger volume, lower cost technologies,” says Nathan.
“Some of that will come from upscaling our current electrolysers, but not a huge amount because the biggest cost of electrolyser hydrogen is from the cost of electricity.”
At this stage, the main way to cheapen electrolyser technology is to make manufacturing cheaper. But other methods of generating hydrogen – like photocatalysis and pyrolysis – could make it cheaper still.
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