A lack of battery storage across the electricity network in Perth and surrounds is the most significant energy problem facing the state, according to recent research from the University of Western Australia.
A lack of battery storage across the electricity network in Perth and surrounds is the most significant energy problem facing the state, according to recent research from the University of Western Australia.
UWA school of design professor Bill Grace expects that solar power, which produces electricity with a low variable cost but on an intermittent basis, will be found on the rooftops of around 60 per cent of households and half of all businesses by 2050.
Many will also use decentralised battery storage.
It means about 85 per cent of Perth’s electricity demand would be supplied by solar, Professor Grace estimates, requiring the state’s South Western Interconnected System to supply electricity only to complement private power supplies.
“If private solar generation exceeds total demand in the middle of the day (which is predicted to occur from the early 2020s), solar generation will be restricted by the network operator due the lack of network storage capacity,” Professor Grace said.
“Emission free power would then be substituted by highly polluting, expensive fossil fuel based generation, simply to enable the network to operate conventionally.”
A large amount of storage would then be required to ensure that the extra solar energy generated during the day could be reused at night, with Professor Grace estimating about 32 gigawatt hours of storage capacity would be needed by 2050.
He said pumped hydro storage at Perth's major dams, similar to the $2 billion investment planned by the federal government to expand the Snowy Hydro scheme, would be the best option for smoothing power supplies.
To put the numbers in context, Prime Minister Malcolm Turnbull has predicted Snowy Hydro phase 2 could store up to 350GWh.
Professor Grace said the strong projected take up of private solar in WA raised questions about the need for large-scale investment into renewables.
He estimated that about 2.25GW of renewable capacity would be needed for the south-west network by 2050.
There are currently about 5GW of installed capacity on the system, so Professor Grace’s research indicates that it may not be necessary to replace all of that with centralised renewable generation in order to achieve even a 100 per cent renewable energy target.
“It may be more appropriate to allow private generation to largely meet this (greenhouse gas reduction) objective while planning for a completely renewable system by 2050,” Professor Grace said.
“By then it is likely much less renewable energy of network scale will be required to supplement private solar generation.”
Storage capacity
WA has been a leader in storage take-up.
Earlier this month, two WA companies announced they will bid to build a $150 million battery storage facility in South Australia, competing with internet billionaire Elon Musk.
Alinta Energy is currently installing a 30 megawatt battery at its Newman power station, which has a generation capacity of around 180MW.
That station supplies BHP’s grid at the Mt Newman operation, which does not connect into the rest of the North West Interconnected system.
Government owned generator Synergy has installed a 1MW capacity battery at Alkimos, while Australian Vanadium installed the first commercial scale vanadium battery in Australia near Busselton last year.
