Australia’s energy and environment minister has hailed the country’s accelerating residential energy storage sales as a report has emerged from Chief Scientist Dr Alan Finkel which says the “financial equation is straightforward” for adding batteries to home PV systems.

Finkel’s office produced reports during 2017 which advised the government on the power market, opportunities and challenges for renewables and decarbonisation and the role of clean energy technologies in boosting the resiliency of energy networks across Australia. At the tail end of the year, he also published a report on the “transformative role” of energy storage.

Finkel had said that there should be better market designs to incentivise peak shifting of solar and other forms of generation, which could be done with battery energy storage in those reports. Nonetheless, in an Occasional Paper on energy storage which he has just put his name to, the Chief Scientist has said that it already makes financial sense for home PV system owners to combine them with energy storage systems.

“The financial equation [to buy energy storage systems] is straightforward, driven by the difference in the high price to purchase electricity compared with the low price to sell it to the grid,” the paper said.

Over 1.8 million Australian rooftops are fitted with solar PV, most of which are residential. Feeding solar into the grid only makes the seller around AU$0.08 per kWh, to give the ballpark figure quoted in Finkel’s paper, while retail prices the same homeowner would pay for grid power are at around AU$0.30 per kWh. Storing the electricity generated and self-consuming it onsite instead therefore represents a significant potential for savings.

Minister for Energy and the Environment Josh Frydenberg hailed the success of the market. Finkel found that around 21,000 home systems were installed during 2017, which Frydenberg claimed made Australia a world leader for installed capacity of batteries, when taken with large grid-scale projects such as Tesla-Neoen’s 129MWh Hornsdale battery project in South Australia and two others which Frydenberg’s government funded the installation of.

“We are now not only the world leader in the use of rooftop solar, but also the world leader in the installation of residential battery storage by power capacity. As more renewable energy – mainly in the form of solar and wind power – enters our electricity grid, the need for energy storage solutions grows,” Frydenberg said.

“This is why the Turnbull Government put energy storage on the agenda – to deliver a more affordable and reliable energy system for Australians.”

The minister also hailed the arrival of virtual power plant (VPP) projects, of which Australia is already hosting several, backed by Frydenberg’s government.