In the 2016 South Australia Blackout , a storm lead to a cascading failure, with in turn left 1/6 of the continent without electricity. Fortunately, this is not a densely populated area even for australian circumstances, so it affected some 1.5 mio people (out of 20 mio total for all of Australia) - still quite a lot of people. The news of a 73-year-old Tesla Powerwall owner powering through this outage without even noticing made the headlines in the aftermath, and in consequence demand for PV + Battery combination surged. In total, more than 50GWh have been installed in 2016 alone, and demand is climbing.
This ties into a three year old discussion about the grid death spiral which is scaring electricty providers: As more and more households become grid-independent, cost for maintaining the grid and providing electricity becomes higher, making the grid eventually economically infeasible, and making going off-grid mandatory - which for some consumers may be impossible:
The risk for the companies is that when people get the option of putting solar panels on their roofs and installing batteries and cutting the cord, demand will fall sharply. The people who end up left on the network will be the only ones left paying.
They will be stuck with extremely high network charges, forcing even more people off the network, pushing network charges higher still. It is what Ms Carter calls “your death spiral scenario”.
On the other hand, savings through a Powerwall or other battery devices on top of a PV installation can be spectacular - one owner in Australia reports a 92% bill reduction .