Tesla Powerwall 2

Sometimes yes, and the reason is your existing solar. Powerwall 2 is AC coupled. It sits alongside whatever inverter you already have and does not care what brand it is, which makes it the cleaner retrofit on a home with working solar. Powerwall 3 replaces the inverter, so on a retrofit you may be paying to make good hardware redundant. If you are starting from nothing, Powerwall 3 is usually the better build. If you have five-year-old panels and an inverter with warranty left, Powerwall 2 often wins. We set out [why the two will coexist](/learn/compare-tesla-powerwall-3-and-2).

The same two that apply to any eligible battery, and they stack. The federal Cheaper Home Batteries Program discounts the installed price through the STC mechanism, and the WA Residential Battery Scheme pays $130 per usable kWh for Synergy customers, capped at $1,300. Powerwall 2's 13.5kWh is well past the cap, so it attracts the maximum. Virtual power plant participation is mandatory for the WA rebate. Figures move on published timetables and your quote carries the current ones. See [the WA battery rebate options](/solar-battery-rebate).

Yes, and the upgrade path has widened. Additional Powerwall 2 units can be added on the same Gateway, and Tesla has since opened a pathway that changes what an existing Powerwall 2 owner can do next. We have covered what that means in practice in [your Powerwall 2 just got a big upgrade path](/learn/powerwall-2-got-a-big-upgrade-path). Whether it applies to your site depends on your Gateway generation and switchboard, which we check before quoting.

13.5kWh, at 100% depth of discharge, with 5kW continuous output. The depth of discharge figure matters more than people expect. A battery quoted at nominal capacity with an 80% or 90% usable limit gives you less than the number on the brochure, and the WA rebate is paid per *usable* kWh, not nominal. The [Powerwall 2 datasheet](/media/2020/11/Powerwall_2_AC_Datasheet_EN_NA.pdf) and the [Gateway 2 datasheet](/media/2020/11/Tesla_Backup_Gateway_2_Datasheet_EN-NA.pdf) carry the full specifications.

It depends on when you use power, not how much. Under Synergy's buyback scheme, exported energy earns 10 c/kWh between 3pm and 9pm and 2 c/kWh outside that window, while imported power on Home Plan A1 costs around 33 c/kWh. A battery is worth it when it moves a lot of energy from the cheap window into the expensive one, which means high evening use: ducted aircon running past sunset, a pool pump, someone home at night. If your bill is already low because daytime solar covers it, the payback is long and we will tell you so. There is a fuller treatment in [is Tesla Powerwall worth it](/learn/is-tesla-powerwall-worth-it), and buyback rates are reviewed annually.