The Ultimate Guide to Tesla Powerwall Sizes

The Ultimate Guide to Tesla Powerwall Sizes

Tesla’s Powerwall is a next-gen piece of technology that allows for storing power off-grid, but finding out about the different options can be confusing. Depending on home size, electricity needs, location, and other factors, the number of Tesla Powerwalls necessary can change dramatically.

Tesla’s Powerwall 2 is only available in one size, but multiple can be connected together to expand the power available. Each one has a 13.5 kWh capacity. The original Powerwall was available at a smaller size but has been discontinued in favor of the upgraded model.

Tesla’s Powerwalls have a lot more to them than simple size, thanks to the nature of electricity and storage. For more information about what size and amount are right, read below.

The Powerwall 2 Is the Ideal Choice for Any Home

The Powerwall 2 is the leading choice for almost anyone looking to get a Powerwall installed in their home. The original Powerwall stopped production in 2017 when the 2nd model was announced; with the included upgrades and sleek new look, there is little reason to ever seek out the original. It is no longer sold, either, meaning Tesla has fully moved on to this 2nd addition.

The Tesla Powerwall 2 has a 13.5 kWh energy capacity and can provide continuous power of 5 kW.The exact numbers will vary depending on location, temperature, and general climate, but numbers around these can be expected. Across the United States, most homes consume an average of 28 kWh of electricity per day. This means that, on average, a single Powerwall 2 unit can power a home for 12 hours off of a full charge.

The main differences in size between Tesla Powerwall units are how many are chained together. We’ll get into more detail about the specifics of how linking together multiple units works in the next section, but most homes end up installing two or three Powerwall 2 units.

What to Know About the Powerwall 2

There are some essential basics to cover about the Powerwall 2 and general rechargeable battery banks. Understanding how the Powerwall works will help you figure out if the Powerwall is a good option for you, how many you need, and what additional technology is necessary to get the full experience.

The Powerwall 2 is a rechargeable lithium-ion battery. Lithium-ion batteries are relatively new technology, especially when used at the size of the Powerwall. They are incredibly efficient at storing energy, which is what the Powerwall strives to do.

The reasons to get something like the Powerwall 2 can be numerous, including:

  • Powering your home with solar energy at any time
  • Reducing power-grid usage
  • Saving extra power for future use
  • Use as a backup during outages

Many people will likely end up using the Powerwall for all of these reasons. Of course, to get the maximum use out of the technology, some other systems are required.

In addition to the Powerwall, customers will want solar panels and need an officially licensed electrician to install them. If you are using an older model Powerwall, such as the original, an inverter will also need to be purchased. Although prices will change depending on your location, those in the United States can expect to spend roughly 3,000 to 5,000 dollars more than the price of the Powerwall to get it up and running.

Although solar panels or another form of alternative energy are not required to use a Powerwall, the vast majority of users will likely want something set up. Otherwise, the Powerwall will not be able to charge energy itself and will mostly serve merely as a backup generator.

Compared to other power bank units from Tesla, the Powerwall 2 is the only one currently available for home use. They initially launched the Powerwall, which has now been replaced entirely by the Powerwall 2. Tesla also offers the Powerpack, a much larger alternative for corporations or businesses which use much more power.

Comparing the Powerwall And Powerwall 2

When Tesla switched entirely over to the second generation of their Powerwall units, they did so thanks to some tremendous technological improvements over the first. Traditionally, Tesla prefers to apply upgrades to its offerings through virtual firmware updates that improve efficiency or introduce new features. Introducing a whole new hardware line meant that some changes were significant.

Some of the main differences between the Powerwall and Powerwall 2 include:

  • The inclusion of an inverter
  • A larger power capacity
  • A sleek new design
  • Tesla app Integration
  • General hardware upgrades

The Included Inverter

An inverter is a piece of technology that, in the simplest terms, converts energy from one source into electricity the battery can actually store. For the vast majority of Powerwalls of either generation, this is most applicable when converting solar panel energy into stored electricity.

When using a Powerwall to store energy, a converter is necessary for maximizing storage space. They are often expensive, especially when they can support large currents such as what is needed for a multiple-Powerwall-setup. With the original model, the inverter alone frequently added another few thousand dollars, not including the installation cost.

When the Powerwall 2 launched, Tesla opted to include a converter in the build for no additional cost. While customers can opt-out of the inverter if they have one previously set-up or are a particular case, the majority of people are happy to see it included.

The inclusion of a necessary piece of technology to make the Powerwall worth it is an excellent upgrade in its own right. Still, it also represented Tesla becoming a bit more honest with the price of installation of most Powerwall units. Realistically, getting a Powerwall at your home often ends up being 3,000 to 5,000 dollars more expensive than the cost of the unit once installation costs and permits are factored in. Tesla addressed this by reducing it slightly with the inclusion of an inverter, which was a significant step in the right direction.

For more information on the differences between models with an inverter and without, along with what the inverter is actually used for, read here.

A Larger Power Capacity

While each of these is noteworthy, the most considerable benefit for the majority of people is the upgraded size. The original Powerwall had a size of only 6.4 kWh – enough to power the average household for only 6 hours. The upgraded storage capacity of the Powerwall 2 means that some homes will be happy purchasing only one.

The increase in power capacity also came with an increase in efficiency, often reducing the average cost of each kilowatt. This is mainly due to better cooling in the Powerwall, allowing the battery to operate at better efficiency in a broader range of temperatures. The more efficient the device, odds are the less of them you’ll need to fully power your home.

A Sleek New Design

Although the least impressive upgrade between models, many customers will appreciate the new look that Tesla applied to the Powerwall when the second model launched. Abandoning the rounded design has resulted in a piece of technology that looks much more modern and slimmed down.

Initially, the Powerwall shared much with Tesla’s other designs, including an almost bubble-like exterior that extended rounded edges in all directions. It also had a minimalist white design with simple branding, which was kept through the second Powerwall iteration.

When Tesla ditched the awkward edges for a simple, straight rectangle look, it made the whole unit blend better into the vast majority of houses. While a small upgrade, more aesthetically focused people will appreciate the changes.

Tesla App Integration

Tesla’s app integration is a large quality of life upgrade for all of their cars, and the Powerwall 2 is no different. With the upgraded model, users can now track where their power is going, what source it is coming from, how much is left, and change the Powerwall’s mode – all from their smartphone.

It is a considerable upgrade in user experience, and the available information also helps ensure that you can safely monitor the status of your Powerwall in case anything goes wrong.

More information on the Tesla app and customization options for your Powerwall can be found here.

General Hardware Upgrades

Finally, Tesla just generally improved the hardware used in the Powerwall 2 in comparison to the first. Better components and layout have made a few minor upgrades possible, such as now being able to install the unit either standing up or laying down.

Improvements to the batterie’s cooling technology have made the whole unit function much better in a wider range of temperatures and allow higher continuous power. Even the small details such as the now included inverter have better hardware on both the internal and external components.

Connecting Multiple Powerwalls Together Increases Size

Connecting multiple Powerwall units together is the only way to effectively increase the size of a unit and get more power out of it. Before deciding on this course of action, it is important to look at your energy usage and gather quotes from various solar panel specialists. That will help you choose how many you need or want.

For the Powerwall 2, up to 10 units can be connected together. Technically, this means that you can choose to store up to 13,500 kWh of energy at your home. This is, of course, the extreme minority of users and would be an expensive undertaking. For more information on the technical aspects of the Powerwall 2, look at Tesla’s official page here.

Most Homes Will Connect Multiple Powerwalls Together

With the Powerwall 2’s energy capacity of 13.5 kWh, it can power the average home for about 12 hours. Depending on your specific needs and energy usage, you may be more than happy with that amount. However, many others decide that they would like a larger Powerwall grid set up for their home.

When deciding how many Powerwalls are necessary, consider what you wish to use the technology for. 12 hours of power is likely more than enough for people who will treat their Powerwall as a backup, for instance, but will be found lacking by those looking to get most of their power from the units. More information on the length of a charge can be found here.

If you plan on using your Powerwall to provide the vast majority of your energy throughout the day and night, upgrading to two Powerwalls is likely the best option. Heavy users of electricity may want three or even four if the house is large.

Although the Powerwall 2 increased its power capacity over the original, many homes may still want or need two or more units installed. When two Powerwall units are installed together, the size effectively doubles.This holds true regardless of how many are connected, tripling for three or quadrupling for four.

When multiple Powerwalls are daisy-chained together, more solar panels will also be required (unless you elect to not use solar to power them). Choosing to add more Powerwalls ends up being more expensive once again than just paying for another unit – consider the cost of energy and length of return before making a decision.

Finding a local Certified Tesla Powerwall Installer in your area is essential both for installing the units and getting the right information for your home. For common questions to ask them, read here.

Choosing the Right Powerwall Size for Your Home

Figuring out exactly how many Powerwalls you need truly comes down to your intentions with the units. Given their vast and varied uses, consumers are likely to use their Powerwalls for a bit of everything. Even with that information, identifying what you are most interested in will make the process of choosing a size much more straightforward.

Common goals with a Powerwall unit include:

  • Switching to solar energy
  • Having an effective backup

Any Powerwall unit from Tesla is more than capable of doing any of these things, but the size requirements for each are different.

Switching to Solar Energy

Switching to full solar or alternative energy is a great goal, but it is often too lofty and expensive for many people to achieve. As previously stated, the price of installing Powerwall units is quite high. While there are discounts for purchasing multiple units, the cost of becoming fully energy independent is still relatively high.

To switch to full solar energy, you have to capture enough energy during the day to last through the night. This is while also using power during the day, making charging that much more of a challenge.

The majority of households use most of their energy while they cannot get more solar energy – whether at dusk, as the sun sets, or at night. This means that your home must be able to store a significant amount of the energy you receive, likely above 50%.

Figuring out how much power your home uses on an average day is especially important for this purpose. Then, calculate how much energy your solar panels can generate on an average day. The less energy you can generate during the day, the less likely switching to solar becomes – and the more expensive the Powerwall size you need.

It is instead much more realistic for most people to switch to solar energy for some of their needs, reducing what they pay overall for energy. In this case, fewer Powerwalls are necessary, although multiple is still almost certainly worth it, especially if electricity is expensive in your area.

Using the Powerwall As an Effective Backup

Having the security and peace of mind from a Powerwall battery is a great goal and one that can often be achieved reasonably cheaply. In fact, the Powerwall can store energy directly from the grid, meaning that solar panels or another form of energy can be cut entirely if you so choose.

As stated previously, the average home can be powered for about 12 hours off of one fully charged Powerwall. Taking a look at your specific numbers is still essential to ensure you are secure for as long of a period as you wish.

If blackouts in your area often last longer than 12 hours, it may be worthwhile to grab a second Powerwall. This is especially true if you want to continue to use power like normal during a blackout rather than conserving it – doing things like keeping the television and all the lights on will significantly reduce your available backup time.


Tesla’s Powerwalls do not come in multiple sizes anymore. Ever since the release of the Powerwall 2, a single, 13.5 kWh capacity is all that is available – but to increase the amount of available power, multiple can be connected. This is a system that allows for significant customizability to meet your specific needs and goals.

Originally, Tesla released the Powerwall’s first model at the size of 6.4 kWh. This is likely far too small for most people, and Tesla no longer produces this model, so finding one is almost certainly not worth the time or effort.

Deciding what size Powerwall you may need comes down to your goals for the system and budget. Alternative energy storage can quickly get expensive, especially as government subsidies begin disappearing in the coming years.

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The articles here on are created by Greg, a Tesla vehicle and Tesla solar expert with nearly half a decade of hands-on experience. The information on this site is fact-checked and tested in-person to ensure the best possible level of accuracy.

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