What’s the Difference Before and After Installing a Battery for a 20kW Solar PV System?

by | Aug 21, 2025

Here’s a real-world example that shows the impact clearly:

 

🔋 Before Installing the Battery

  • PV system: 20kW
  • Average night-time electricity usage: 12.34 kWh
  • Quarterly electricity bill: $234 AUD (to pay)

 

🔋 After Installing a 10kWh Battery

  • Average night-time usage drops to: 4.38 kWh
  • Quarterly electricity bill: –$190 AUD (credit)
  • Total quarterly savings: $234 + $190 = $424 AUD

 

This is with just a 10kWh battery. If you install a larger 50kWh battery, your energy independence and savings will multiply, especially for homes with high energy usage or EV charging needs.

Energy storage isn’t just about backup—it’s a smart way to maximize your solar investment and take control of your electricity bill.