Tesla Powerwall 3 home battery
Powerwall 3 pairs 13.5 kWh of storage with an integrated solar inverter. Start with what you want to run after sunset, then decide which circuits should stay on during a power cut. Those are two different sizing decisions.
Powerwall 3 versus a Powerwall 3 Expansion
| Equipment | Energy capacity | What changes |
|---|---|---|
| One Powerwall 3 | 13.5 kWh | Includes a solar inverter |
| One Powerwall 3 + one Expansion | 27 kWh combined | Adds storage, not a second inverter |
These figures are stored energy. Available output, reserve settings, phase arrangements and site conditions affect what the house can actually draw.
One Powerwall or an Expansion unit?
Tesla lists Powerwall 3 at 13.5 kWh. A Powerwall 3 Expansion adds another 13.5 kWh of storage. The extra energy can extend run time; it does not add a second inverter. Ask for both available energy and configured backup output on your proposal.
Already have solar or a Powerwall 2?
Send your solar inverter model and any existing Powerwall details. A Powerwall 3 Expansion is an accessory for Powerwall 3; we assess an existing Powerwall 2 installation separately. For new solar, we can compare a design using the integrated inverter with a retrofit that retains suitable equipment.
Choose what the gateway will back up
List the fridge, lights, internet and any larger loads separately. Your supply phase, circuit layout and proposed gateway arrangement determine what can actually run. We’ll show the included circuits and any switchboard changes before you decide.
How long could the essentials stay on?
If 8 kWh is available for backup and the fridge, lights and router draw an average of 0.5 kW, the simple estimate is 16 hours before losses. Add a 2 kW heater and the same calculation falls to about three hours. Your starting charge and actual loads matter more than the headline capacity.
Tell us if you have three-phase power, a pool pump or ducted cooling. We will identify the backed-up circuits and gateway arrangement in the quote rather than promise whole-home or three-phase backup from the battery name alone.
What will the installed system cost?
A useful Tesla quote separates the battery and inverter from switchboard work, backup wiring and commissioning. Ask for the total installed price, any eligible federal battery discount and the balance you pay. Future bill savings are a separate estimate, not a deduction from the invoice.
We check the proposed equipment and your property against the Clean Energy Regulator’s battery eligibility rules. We also identify the manufacturer’s warranty for the quoted model and who to contact for warranty support.
Tesla battery questions
Tesla product information · Tesla guidance for existing Powerwall 2 owners
Local installation and connection advice: Melbourne · Sydney.
