Lead researcher Vanika Sharma, a doctoral candidate at UniSA's School of Engineering, found that an optimally sized battery could be economically beneficial in SA due to the government subsidies, abundant sunlight, high electricity costs and relatively low feed-in tariffs.
“The crucial thing is to ensure you are getting the right size battery, and getting it at the right price,” said Sharma, who published a paper on her findings in the journal Renewable Energy.
“But if you are, then you can now have a battery that will pay itself off in the warranty period, which is the main concern for most people.”
Sharma has developed a method whereby people can calculate whether it would be economically wise to obtain an optimally sized battery, the cost of which could be paid off.
“The optimal battery size depends on various factors, such as load and PV generation patterns, battery cost and characteristics, retail price and feed-in-tariff of grid electricity,” she said. “But this method can assess this all efficiently, and that allows people to make the right choice for their circumstances.
“Right now, in South Australia, the break-even cost for installing a battery using this method is about $400 per kilowatt hour of battery capacity, and with the current subsidies of $500 per kilowatt hour, and retail prices on some batteries lower than $900 per kilowatt hour, you can have a cost-effective system.”
Sharma and her fellow researchers, Dr Mohammed Haque and Professor Mahfuz Aziz, are now trying to find out if storage alternatives, such as shared "community" batteries, may be better as far as both cost and system efficiency go.
“The focus of the research is to minimise the waste of PV, and so we’re also looking at whether it is more effective to have batteries on every home, or a central battery that could accommodate more PV, which would then also save distribution costs for providers,” said Sharma.
Added Dr Haque: “The residential battery energy storage systems not only provide financial benefit to the customers but also address some of the operational issues associated with power generation, transmission and distribution."
And Prof Aziz said: “The use of battery energy storage systems is likely to proliferate in the years to come. Future research and development should focus on how to leverage such storage to improve power system operation.”