Tesla Powerwall battery: A buying guide

The latest Tesla battery to hit Australian shores is the Powerwall 3; it comes with a built-in inverter and has the same capacity as the original Powerwall unit. Tesla’s Powerwall 2 is no longer available, but remains a reliable solar battery for Australian homeowners that own one.

The Tesla Powerwall 3 battery is approved by the Clean Energy Council which means that homeowners and businesses that install the unit can claim the federal battery storage rebate.

In this guide we cover:

• Tesla Powerwall cost
• Tesla battery specs
• How the Powerwall works
• What savings will the Tesla Powerwall deliver
• Installation

Telsa Powerwall costs and prices

The Tesla Powerwall costs between $12,000 – $14,000, which includes full installation. The price for the Tesla Powerwall is for the battery alone and does not include the cost of solar panels. A 6.6kW solar panel system is typically a good accompaniment for the Tesla battery and would increase the full system cost to between $18,000 – $22,000.

The Tesla Powerwall 3 price is slightly more expensive than its competitors, but it has a few more features to make up for the additional cost.

Tesla Powerwall prices:

The price range reflects the variance in the cost of solar panels and not solar battery prices.

Our side-by-side comparison of the Tesla Powerwall 2 and Powerwall 3, reveals a few key differences in the latest version of the battery.

Tesla Powerwall battery specifications

The Australian Powerwall is a lithium-ion phosphate (LFP) battery with a usable capacity of 13.5kWh. The Tesla Powerwall 2 battery was scalable up to 10 units, while the Powerwall 3 is stackable for up to four units.

The table below shows the full specs for the Tesla battery:

Tesla Powerwall battery specs table:

Design and install capabilities

The Powerwall features a slim, attractive design that is compact enough to install in most households: typically, outside on a wall. The Tesla Powerwall battery is currently not suitable for off-grid solar installations. It is also not possible to install a Powerwall 2 with a Powerwall 3 battery.

How the Tesla battery works

Tesla’s Powerwall battery can either be installed with an existing solar system or combined with an entirely new system purchase. The battery stores the excess solar power that is generated by your solar system. Power from the battery can then be used at a later time when your panels are not producing electricity, ie. During the evening.

The Powerwall battery operates as most solar batteries do; except that it has its own built-in inverter. It requires a solar panel array and it comes with a backup gateway. The solar panels convert solar energy into usable electricity. The Powerwall unit stores the excess power that your panel array generates throughout the day.

The Powerwall 3 works in the much the same way as its predecessor. They key difference is, it has its own built-in inverter.

Compatible inverters

For existing solar panel owners, one key feature of the Tesla Powerwall is that it can be paired with any inverter or brand of micro-inverters.

Back-up power

The Tesla Powerwall can provide power back-up during the event of a grid outage.

Take advantage of market prices

The Tesla batteries' ‘Advanced time-based control’ mode allows you to take advantage of fluctuating electricity prices. You can set your Powerwall to this mode using the Tesla Mobile App, which also allows you to keep track of your energy use. You can then minimise your electricity costs by selling power back to the grid when spot prices are very high.

What savings will I be able to make?

Calculating the savings effect of the Powerwall battery is complex, results depend on your specific household circumstances. The split of your electricity use between day and night is a factor, as is, the amount of solar power that your panels generate.

To highlight the savings and payback potential of the Tesla battery, we consider a typical household in Brisbane. For this scenario, we pair a Tesla battery with 8kW of solar panels. Assuming a quarterly electricity bill of $750, the graphic below shows savings and payback results from our calculator:

Solar panels deliver faster payback

Typically, solar panels deliver faster system paybacks. If you are investigating an entirely new hybrid solar system (solar panels and Tesla battery), you can use this calculator to estimate your solar savings.

Already own solar panels?

If you already have solar panels, you need to perform a different calculation, as you purely want to assess the merit of adding a battery to your existing system. The solar battery calculator will allow you to weigh up the effectiveness of the Powerwall unit.

Installation of the Tesla Powerwall

You need to purchase a Tesla Powerwall battery through one of Tesla’s certified installer partners, many of which you can access via our quote service. As with any solar installation, conducting a thorough review of the various warranties and not simply buying on price alone is key to the longevity and ongoing operation of your panel and battery system.