An energy storage project that has been dubbed the world's smallest version of the Snowy Mountains hydroelectric power plant is taking shape in Western Australia.
Key points:Pumped hydro is long-term energy storage involving the transfer of water between two reservoirsA start-up firm will build the world's smallest pumped hydro project at Walpole in Western AustraliaExperts say long-term energy storage critical to making power systems 100 per cent renewable
Power Research and Development, a WA-based company, wants to build a 1.5-megawatt pumped hydro project capable of powering the town of Walpole on the state's south coast for up to 70 hours.
The proposal, which is backed by state-owned electricity distributor Western Power, would help overcome crippling power cuts that can hit the popular tourist spot for hours at a time.
Pumped hydro projects typically work by pumping water uphill from one dam to another during periods when power is cheap.
The water is then released downhill through a generator to produce electricity when supply is low and prices are high.
In PRD's case, it will install solar panels and batteries to provide its own power for pumping.
Colin Stonehouse from PRD said the need for storage was one of the biggest challenges facing the electricity system as ever-increasing amounts of intermittent renewable energy such as wind and solar power came on stream.
Mr Stonehouse said this was because supply from renewable sources was uncontrolled and often did not match demand.
He said being able to store excess output and use that power when it was needed was crucial to the aims of decarbonising the electricity system.
Energy storage 'like a bank'
"It's like banking your electricity," Mr Stonehouse said.
"You put your electricity into the bank because you've got more than you need.
"And then you take it back out of the bank later in the day because you haven't got as much as you want at that point in time."
Under PRD's plans, it will build two reservoirs — effectively farm dams — with a difference in elevation of about 100 metres.
The company aims to provide energy storage services to commercial and rural businesses in the area.
But it has also secured a contract with Western Power to supply back-up power to Walpole during periods of disruption to the main transmission line from Albany, 120 kilometres to the east.
Mr Stonehouse said the motivation for the project was Walpole's notoriously unreliable electricity supply, which is the result of its position at the edge of the grid.
"We can help with that reliability by putting storage out there at the edge of the grid," he said.
"It helps to stabilise things like the voltage.
"But then we can also provide services back into the centre of the grid for things like capacity during periods of peak demand."
'World's smallest' pumped hydro
WA Energy Minister Bill Johnston said the Walpole project was based on the same principles as the federal government's planned expansion of the Snowy Hydro scheme.
That upgrade is expected to cost more than $5 billion and would have a capacity of 2000 megawatt — enough to power 500,000 homes.
Mr Johnston said that while pumped hydro schemes were normally giant projects, the WA venture was believed to be the smallest of its type anywhere in Australia and perhaps even the world.
Crucially, he said the development would be more robust than a battery, which was only able to provide power for a short amount of time.
"This is a unique installation," Mr Johnston said.
"It allows us to have what in the business we call long-term storage … that will last for hours or days, rather than out of a battery that might last for minutes or an hour."
Despite the project's small size, Mr Johnston said it could serve as a template for other parts of the state and beyond, provided it could deliver reliable power and was competitively priced.
He noted that in many places at the edge of the grid, reliability was a major problem, and these were the locations where "micro" pumped hydro schemes could work.
"There's really lots of opportunities for a lot more projects like this, all over the southwest of the state," the Minister said.
"Obviously, you need a bit of elevation, and you need water.
"So, some parts of Western Australia, and in the more remote areas, there's not a lot of water, and … these projects wouldn't work.
"But in the south-west corner, there's probably a lot of opportunities for these types of projects."
Power fix 'long overdue'
Jennifer Willcox has been campaigning for better power services in Walpole since moving to the town almost 30 years ago, the
As far as she is concerned, the proposed project could not come soon enough.
She noted that "practically everyone" in the town had their own diesel generator to keep the lights on when supplies to Walpole were cut.
But she said a more sustainable and equitable solution was long overdue.
"In recent years, with the huge dependence on communications, power isn't just loss of lights and loss of water for rural areas," Ms Willcox said.
"It is loss of communication and even landlines because our local exchange has a battery back-up; our two towers have battery back-ups.
"But when the power outage is for such lengths of time the batteries become depleted and so then the towers fail, the landline fails and we're out of power.
"So, Walpole is totally isolated from the rest of the world."
Posted 31 Oct 202131 Oct 2021Sun 31 Oct 2021 at 10:37pmShareCopy linkFacebookTwitterArticle share optionsShare this onFacebookTwitterLinkedInSend this byEmailMessengerCopy linkWhatsApp