Home battery boom: The who, what, where and why behind record storage numbers

Home batteries were installed in record numbers in almost every state and territory in Australia in 2022, as power prices hit record new highs and tens of thousands more households opted to invest – or invest further – in energy independence.

As reported last week on One Step Off The Grid sister site, RenewEconomy, data from SunWiz shows 47,100 home batteries were added to the national total in 2022, which by the end of the year had reached 180,000 – the equivalent to 1920MWh of energy storage capacity or nearly 2GWh.

This is a new annual record for home battery installations in Australia, and a 55 per cent increase on the numbers from 2021.

So what sort of batteries are Australian households installing, and what sort of customers are installing them – and where?

As it happens, SunWiz has some interesting data on that too.

On a state-by-state basis, New South Wales leads the nation on the cumulative number of behind-the-meter batteries installed to date with 51,629 (see map below) of the national total.

Second is Victoria, which has a total of 44,284 small-scale batteries installed, according to SunWiz – no doubt boosted by that state’s own ongoing home battery subsidy.

Third is South Australia, which SunWiz managing director Warwick Johnston says is “certainly punching above its weight” on batteries, thanks in part to the state’s high rooftop PV uptake and virtual power plant leadership.

To break the locational data down further, SunWiz has used data from the Australian Energy Market Operator’s DER Register to get a postcode-level look at where batteries are being installed in the NEM.

The chart below shows the top 40 postcodes in the nation for battery connections according to the DERR, with a “leaderboard dominated by SA,” SunWiz says, and a small number of Queensland and ACT postcodes in the mix.

As for the who, SunWiz says of the customers behind this year’s record sales, the majority – 55% – were buying a battery at the same time as a new rooftop solar system, going for the whole package on home energy independence straight off the bat.

This is hardly surprising, given the direction energy prices have been headed, and the increasing number of solar and battery package and finance deals on offer from both solar companies and energy retailers.

For the remaining 45% of sales and installations for the year, 5% added more battery capacity to existing energy storage systems, 25% added a battery to existing rooftop solar system, 5% added a battery to an expanded rooftop solar system and 10% added a battery to a replacement rooftop system.

On the type of batteries people are buying, SunWiz doesn’t divide the sales into brands, but it has put together a chart tracking the size of the home batteries people are installing, which offers some clues to which brands these size-ranges might include.

The chart shows that, just as rooftop solar system sizes have been getting bigger, customers are making a shift towards bigger home batteries, ranging between 9kWh and 14kWh – and averaging out to 12.5kWh/system.

For interest’s sake, we note that the 9-14kWh capacity range takes in the Tesla Powerwall (13.5kWh), the SonnenBatterie hybrid, which ranges in size up to 15kWh, Sungrow’s 12.8kWh battery, and LG Energy Solution’s latest RESU prime range, which starts at 9.6kWh – just to name a few.