Tesla Powerwall Voltage Explained

Tesla Powerwall Voltage Explained

The Tesla Powerwall is an energy storage device for use with or without solar energy. There are some big claims as to what the Powerwall can do, particularly about its voltage. It can be hard to explain to those who are not familiar with how voltage works, but it is a good idea to familiarize yourself with the facts either way.

The Tesla Powerwall’s voltage runs at around 350-450 volts. It also holds 14 kWh (kilowatt-hours) of backup energy. These numbers make the Powerwall one of the best home battery systems on the market.

With the price of solar energy cheapening around the world, a battery such as the Powerwall can become a necessity. There is a lot more to the Powerwall than just its voltage, however, so keep reading to find out if this home energy system is for you.

How Powerwall’s Voltage Works

The Tesla Powerwall is a rechargeable battery system. It uses a lithium-ion battery pack to achieve its solar rechargeability. The benefit of a lithium-ion battery is its lightness and the efficiency of its energy use.

The Powerwall boasts a 90% “round-trip efficiency,” meaning it is quite an efficient battery. Comparatively, other brands usually have an 80% round-trip efficiency. This is an important aspect of a good battery system, as this means less energy is being lost in storage.

Tesla’s battery system even allows up to ten Powerwalls for much more storage and to lighten the load on other batteries. To keep its voltage efficient, the Powerwall does supply its power at a low current. This means high-intensity electronic devices can be an issue for the battery early on.

Is the Powerwall’s Voltage Good?

The Tesla Powerwall is considered to be one of the best batteries on the market for voltage. At around 48 VDC (volts of direct current), the Powerwall is very efficient at transmitting energy. Direct benefits based on its voltage can be found below:

  • VDC: VDC is the flow of energy moving in a single direction. Among solar batteries, this places the Powerwall as one of the best in the world. With batteries running at 48 VDC, its one-way efficiency is running at over 90%. This is generally considered amazing for battery efficiency.
  • Nominal Voltage: The Tesla Powerwall is often cited as having a 350-450V nominal. This basically means that this is the amount of energy typically produced by your system. This is a high level of energy potential for a solar battery and can easily compete with some of the world’s top solar battery brands.

To say it in one word, the Powerwall’s voltage is considered great. That 350-450V output is a significant number in the solar energy market and is especially necessary for energy that will be powering your home.

What Voltage Means for You

A battery’s voltage might be its single most important aspect. Voltage is basically a measurement of potential energy within an electrical system. Higher voltage means that a system is more efficient, though it does not mean you necessarily want high voltage.

Some experts even say that since voltage is just a measurement of potential energy or energy pressure, that amperage matters more. Amps are the measurement of the number of electrons flowing through your system. To some, this is the better way to tell the power of your battery, though not necessarily its efficiency.

Electrical current and voltage go hand in hand. If the electrical current is moving fast, then the voltage is the power of this fast electrical energy. For something like a solar battery, this is very important, because high efficiency with a solar energy source means that you are getting the most out of your system.

While voltage is measured with the potential energy of your electrical current as a base, they are not the same thing. To some, high voltage means automatic danger, but a high-voltage system is just a system where there is a lot of efficiency.

How Solar Batteries Work

Solar batteries are a growing market that is seeing people worldwide cutting costs with cheap energy. This energy is not always efficient, however. In recent years big strides have been taken that have allowed the industry to thrive, and the Powerwall is one such stride. If you are confused about how a solar battery operates, read below:

  • Storing Energy: Solar batteries for homes store energy during the day. These batteries work together with solar panels. Throughout the day, your solar panels are collecting energy that you may or may not be using. At any chance they can get, solar batteries are taking excess energy that you are not using to use later.
  • AC Power: Home solar energy batteries typically use alternating current to charge their batteries. This has many benefits, but mainly, AC current can be converted by most solar battery systems into DC or direct current. This allows utilities to be used and electronics to be charged all through one system.

Solar batteries are one step towards efficient, clean energy. These days they are designed with customization and voltage options in mind. The storage for a Powerwall is around 14 kWh, which is enough to keep a home running for a long time even when your energy is constantly being used.

What Can the Powerwall Do For Your Home?

The Powerwall, when paired with solar panels, is a great way to power your home. Typical Powerwall use involves keeping it dormant and storing energy during the day and then powering your home for the evenings. Listed here are some of the best ways the Powerwall uses its efficient energy:

  • Emergency Power: A Tesla Powerwall, if fully charged and if paired with solar panels for further efficiency, can power an average household for around a week. It could even go for longer. Its ability to cleanly store energy and discharge at a fairly high voltage is key to its use as an emergency battery.
  • Energy Monitoring and Control: The Powerwall monitors your energy use with Tesla’s thorough system. Due to its varied customization options, the Powerwall was designed to handle all of its different settings with efficiency in mind and can meet your needs while consistently delivering the right amount of energy.

The Powerwall was designed as a home-use system that saves on energy costs. So of course will be functioning well no matter the settings you apply to it. Small issues occasionally arise when you are combining systems, but it is otherwise a battery that can handle the task of powering your home.

Powerwall Modes and Voltage

Powerwall comes with innovative software that allows your energy needs to be met specifically. Within the industry, it is one of the most customizable home battery systems there is. These operating modes mainly have to do with different priority options between charging and discharging, according to Tesla:

  • Self-Powered Mode: This mode changes the charging priority of the Powerwall to charge using extra solar energy that has been stored. It uses the stored energy from solar panels. In this mode, the Powerwall’s high average voltage remains constant even though you are switching to stored solar energy.
  • Backup Only Mode: This setting is suggested for use when there is a chance of a power outage. As the mode itself states, it is a backup, powering your home using stored solar energy during an outage.

Thanks to the Tesla app and smart interface options, the Powerwall has perhaps the best customization in the market. But if you have voltage concerns, know that the Powerwall’s settings keep voltage constant.

Tesla Powerwall Voltage Compared to Others

The Powerwall is an impressive home battery system, but other brands boast different power ratings, energy capacity, and voltages. Seeing where the Powerwall stacks up is a great way to put the home battery industry into perspective.

Below are some key features of prominent brands compared:

FeaturesTesla Powerwall 2LG RESU PrimeEnphase Encharge 10
Battery MakeLithium-ionLithium-ionLithium-ion phosphate
Nominal Voltage350-450V400V (depending on size)240V
kWh Capacity14.0 kWh16.0 kWh10.08 kWh
Roundtrip Efficiency90%90%89%

The features chosen here are some of the most general, and this is in no way a comprehensive comparison. However, the difference and similarities of these brands are a great way to begin your search for what works for you. It is also important to note that other brands usually offer different sized batteries, so voltage varies.

To meet the needs of your home, you would probably need more than what Enphase Encharge 10 offers, but the Tesla Powerwall and LG RESU prime are fairly even. It could be up to your personal opinion as to which is more efficient that you make your purchase.

The Efficiency of Powerwall and Solar Panels

A Powerwall works best with solar panels. This is true of all solar battery systems. With solar panels installed, the excess energy produced by the panels, the energy not being used during the day, is stored within the battery.

It is suggested for a Tesla Powerwall that your home has a system of over 15 solar panels for peak efficiency. When solar panels are pooled together, their voltage can increase. When low-current, high-voltage solar energy is distributed to your Powerwall system, you could be looking at more energy for yourself at a lower cost.

Without solar panels, the Powerwall’s rate of storage is slow. It can only take energy from the grid at this point and only when energy rates are slower. This is not to say that it will not work, but the battery is better at storing energy from solar panels. You may even notice hits to your voltage efficiency if you use energy from the grid exclusively.

Solar panels are recommended not just because they are the Powerwall’s intended energy supply, but because the output from solar panels with the Powerwall’s storage capabilities saves on your costs. This is not to mention that solar panels are better for the environment than conventional energy sources.

Powerwall System Combination

The Powerwall can be used in combination with other systems, such as with the grid, to provide you energy. It can be added to many different systems as backup power or even for general use. For your voltage efficiency, some combinations will be better than others:

  • Powerwall-Grid Combination: As stated earlier, the Powerwall can be used without solar energy. This involves limiting your settings, but it is still possible for the battery to charge from the grid to capacity. This is suggested as an electricity bill tool to help save money and for outages but can harm your voltage.
  • Powerwall and Electric Cars: The Powerwall can be a benefit for electric car owners. A Powerwall system can be used to charge an electric vehicle through the Powerwall’s home panel. Since an electric car can be charged anywhere from 110-600V, your Powerwall can easily meet this voltage demand.

The Powerwall is a great battery that works with various other systems in order to keep your utility bills low and your energy use efficient. While solar power is the best possible combination with the product, other options do exist that still manage to keep the Powerwall’s efficiency as worth the cost.

Is the Powerwall Price Worth the Voltage

The Tesla Powerwall is considered a well-priced battery for what you’re getting. However. total costs can vary as it might be up to local professionals. In general, you could be looking at between $14000 and $15000 for your install, hardware, the Powerwall itself, and a 10-year warranty.

These costs do not include solar panels, which are suggested to own in tandem with these battery services for peak voltage. The Powerwall can also be a money-saving tool, as Tesla states that it is designed for Federal Tax Credit upon installation. If charged with solar energy, you could qualify for thousands in rebates.

The key feature of the Powerwall is its great efficiency. Without solar panels, it would not be suggested to purchase the Powerwall. You could see less nominal voltage from using energy from the grid, and if your voltage is not consistent with the average, you will not even be saving as much money as you could be switching to solar.

Does Efficiency Remain Consistent Over the Years?

A well maintained Tesla Powerwall can last up to ten years. This is also the length of its warranty. The Powerwall is relatively new to the solar battery scene, and so some might think this 10-year prediction is off. Even if it is, general knowledge of battery lifespan has helped experts predict what may happen to a Powerwall over the years:

  • 1-5 Years: Within four to five years, your Tesla Powerwall will probably be losing some efficiency. If your system is being maintained correctly, this will not be a major hit to your energy needs. The Powerwall will still probably be able to save you money and remain at a solid nominal voltage.
  • 6-10 Years: Within this timeframe, you may notice some significant changes to your battery system. This is common with any kind of battery. Efficiency will be on the decline, and it is even suggested by Tesla that your Powerwall is replaced within this timespan.

Your Powerwall model can also matter, as the Powerwall’s second version can possibly last longer than the first. With any battery system, a loss of efficiency is expected over the years. So consider how long you may be saving money with your system and plan around it.

Powerwall as a Backup-Generator

There may be some who believe the Powerwall can be used as a dedicated home generator, but this is not the case. Batteries that get their power from solar energy or the grid may be able to keep key components of your home running, such as lights and the refrigerator, but if your needs are greater, then a dedicated generator would be best.

The Tesla Powerwall can be used with other backup systems to provide your home with power during emergencies. During an outage, the Powerwall will activate and keep power running until it is out of energy at height efficiency or at the settings you have it on.

Home batteries are not usually equipped to be able to keep powerful equipment running, and certain equipment in a home, such as well pumps, would require more intensive power than a low-current Powerwall can provide.  It should be noted that the Powerwall does not charge from the generator, only through solar panels or the grid.

It is suggested that those who are interested in a Powerwall as a backup generator use the battery as a step between an outage and your generator. A Powerwall will keep your home running. This allows key components of your home to continue to run on electricity without a sudden breakdown, and the generator can easily pick up the slack afterward.


The Tesla Powerwall is a high-performance solar battery with a number of customization options. How its voltage efficiency allows it to function as a top of the line solar battery is through Tesla’s innovative approach to the battery market. Voltage may not be the most important aspect of a solar battery, but it should certainly be considered.

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The articles here on ThatTeslaChannel.com 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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