How many Batteries DO you need? Good question. It depends on what you want your solar batteries to achieve. Most people set out with the aim of reducing their grid electricity imports to zero. As you'll soon see, this lofty energy storage aim will actually be very expensive for most households.
Let's do a crash course on how much energy storage an ordinary Australian household will need. The average Australian home uses roughly 16kWh of electricity per day! Naturally, if you have a house that has a big air-conditioner and pool pump etc, you'll use a lot more than that.
Assuming that most Australians work a 9-5 job and are not home during the daytime, they'll probably only use only around 30% of their electricity during the day, when the sun is up and their solar panels are producing electricity.
That means that they need to buy the other 70% from the grid; so how many solar batteries do you need to need to cover that 70%?