The Tesla Powerwall is a popular battery storage option considered by many American homeowners looking to add energy storage in an effort to reduce their electricity bills and protect themselves from outages. This article will explain what it costs, how it works, and what else you should know if you’re considering a Powerwall for your home.
This is an unbiased review: EnergySage is not paid to review brands or products, nor do we earn money from affiliate advertising in this article. The content of this blog is based on research and information available at the time of writing. Learn more about our mission and how we make money as a company.
Find out what solar + storage costs in your area in 2023
Key takeaways
The Tesla Powerwall costs approximately $10,600 to $12,850 before installation and approximately $14,600 to 16,850 as a total cost (before incentives and taxes).
The Tesla Powerwall’s 13.5 kilowatt-hours (kWh) lithium-ion home battery can help you become more grid-independent and protect you from power outages.
You may need several Powerwall batteries to truly go “off the grid.”
A qualified EnergySage-approved installer can give you the best information about the Tesla home battery system and other energy storage options available for your home.
What’s in this article?
What Tesla Powerwall models are currently available?
Tesla currently offers two Powerwall models: the Tesla Powerwall (also known as the Tesla Powerwall 2) and the Powerwall+. The main difference is that the Powerwall+ includes an integrated inverter and system controller. Most certified installers currently install the Tesla Powerwall+, but you may still be able to install a Powerwall.
How much does the Tesla Powerwall cost?
According to Tesla’s website, the Tesla Powerwall costs approximately $10,600 to $12,850 before installation. Installation is an additional cost that varies based on location and home layout. You can expect an additional $4,000 or so for installation costs, but installation costs can vary widely depending on your electrical setup and other factors.
While this may sound like a lot of money, installing a solar-plus-storage system that includes a Tesla Powerwall can be a worthwhile investment: it helps you harness renewable energy while protecting you from power outages and saving money! You can determine whether the Tesla Powerwall makes sense for you based on a few factors, including:
How your electric utility or retail energy provider structures its rates
Your reasons for installing a solar power battery
If you experience a high number of power outages or blackouts in your area
The solar and storage incentives available in your area (like net metering)
Suppose you want to move towards energy independence truly. In that case, you’ll likely need to install several Powerwall batteries to increase your energy storage capability – this will substantially increase the cost of your solar battery system. However, depending on where you live, you may have access to financial incentives that can reduce your home energy storage installation costs.
Incentives and rebates available for the Tesla Powerwall
While batteries usually require a substantial upfront investment, it’s important to note that the above-mentioned installation costs are before incentives. There are both federal and state or local incentives you may qualify for, including:
The federal investment tax credit
A Powerwall or any energy storage device, aka battery, installed in your home between January 1, 2023 and December 31, 2032 qualifies for the investment tax credit (ITC). This provides a 30 percent tax credit on your Tesla Powerwall installation and is the same credit you get if you install a solar system. Whether you install your Powerwall as part of a solar-plus-storage system, add it to an existing solar system, or want it as stand-alone storage, you’ll be able to receive this incentive.
The only caveat for a battery to qualify for the federal solar tax credit is that it must have a battery capacity of 3 kilowatt-hours (kWh) or greater. So, since a Tesla Powerwall provides 13.5 kWh of backup energy, it qualifies for the ITC.
State-specific incentives
Many states offer additional incentives that can help reduce the cost of your Powerwall, so you’ll want to check to see what’s available in your area – your installer can likely help share information on current programs. For instance, if you live in California, the Self-Generation Incentive Program (SGIP) available through the California Public Utilities Commission (CPUC) offers a rebate of $250/kWh (totaling $3,375 for a Powerwall). You may also qualify for additional rebates through the SGIP based on income and medical eligibility.
In some states like Massachusetts, there are also programs available to incentivize you to connect your Powerwall to the grid – this enables your utility company to draw energy stored in your battery when there’s peak electricity demand to help balance the electric grid.
How the Tesla Powerwall works
The Powerwall pairs well with solar panel systems, especially if your utility has reduced or removed net metering, introduced time-of-use (TOU) rates, or instituted demand charges. A Tesla Powerwall can help power a home, and you can stack up to 10 Tesla Powerwall batteries to increase the capacity of your home energy storage system.
Like many other home battery products, the Tesla Powerwall is sized for day-to-day use and often paired with a solar panel system. When your solar panels produce more electricity than you consume, you can store the excess electricity in the battery system instead of sending it back into the grid. Later, when your panels aren’t producing enough electricity to meet your home’s needs, you can use the electricity stored in your battery instead of buying it from your utility company.
You can also use a Powerwall without solar, but this isn’t as common. If you live in an area with TOU rates, you can charge your Powerwall when your electricity rates are low and discharge it when energy costs are high, providing automatic savings. It will also provide seamless backup power by detecting if there’s an outage and automatically switching to become your home’s main power source.
Is the Tesla Powerwall worth it?
The Tesla Powerwall is one of the market’s most popular home battery options: its price, storage capacity, and continuous power are key metrics that make the Powerwall a competitive home battery option. If you’re looking for a reliable battery that can provide some backup during short outages, the Tesla Powerwall battery could be a great option.
While issues arise with just about every electrical product out there, it’s worth mentioning that some customers have reported communication issues from Tesla when installing these products and service outages.
Key things to know about the Tesla Powerwall
With its launch of the Powerwall in April 2015, Tesla was one of the first companies in the residential energy storage market to make small-scale batteries for home energy storage. Since then, Tesla has released updated Powerwall 2 models in October 2016 and November 2020. In addition to battery storage, you can also purchase Tesla solar panels or a Tesla Solar Roof – though Powerwalls are compatible with just about any solar panel or shingle model, so you don’t have to stick with a full Tesla suite of products.
When evaluating the Powerwall, various metrics and technical specifications are important to keep in mind. Among the most important are the size of the battery (power and capacity), its chemistry, depth of discharge, and round trip efficiency. POWERWALL (ALSO KNOWN AS POWERWALL 2) Powerwall+ (includes integrated solar inverter) Usable capacity13.5 kWh13.5 kWh Continuous maximum power 5.8 kW7 kW (no sun) / 9.6 kW (full sun) Weight 251.3 lb310 lb Dimensions 45.3 in x 29.6 in x 5.75 in62.8 in x 29.7 in x 6.3 in Operating Temperature -4 to 122°F -4 to 122°F
Size
The Tesla Powerwall models offer the same amount of usable energy: 13.5 kWh. Power and usable capacity are two important metrics to keep in mind when comparing the Powerwall to other home storage options.
Power (measured in kilowatts, or kW) determines the maximum amount of electricity that can be output at a single time, while usable capacity (measured in kilowatt-hours, or kWh) is a measure of the maximum amount of electricity stored in your battery on a full charge. The Tesla Powerwall+ boasts a maximum power rating of 7 kW with no sun or 9.6 kW with full sun to go along with 13.5 kWh of usable capacity. The Powerwall 2 offers a maximum power rating of 5.8 kW and 13.5 kWh of usable capacity.
Power vs. capacity
The Powerwall system is also modular, meaning you can add multiple battery products to your storage setup. For example, you might want to install multiple Powerwall batteries for a home with high energy demands and usage. The Tesla website indicates that you can add up to 10 Powerwall batteries to form one large storage system.
Think of your battery like water running through a pipe. The usable energy capacity is the amount of water available to push through the pipe, while power is the size of the pipe itself. Larger pipes allow more water to flow through at once, which depletes the water faster. Similarly, a high power rating battery can deliver more electricity at once but will burn through its available energy capacity faster.
A battery’s power determines what appliances you can run with it simultaneously, while usable capacity determines how long those appliances can be run. Batteries with a higher power rating can power more robust appliances or many appliances at once. In contrast, batteries with a higher usable capacity can store more total energy and thus can run your appliances for longer periods without needing to recharge.
Basic functionality
The functionality of one solar power battery compared to another will vary; some batteries have excellent off-grid capabilities, while others offer software solutions specific to rate arbitrage. Here are the important qualities of the Tesla Powerwall:
Backup power
Tesla has made a concerted effort to ensure their battery solution is compatible with most common brands and types of off-grid and hybrid inverters, making it a good fit for combining with most solar systems. This means that, as long as your Tesla installer uses the correct components, your Tesla Powerwall battery can provide backup power for your home when the grid goes down.
Chemistry
The Tesla Powerwall is a lithium-ion storage product; specifically, it is a lithium nickel manganese cobalt oxide (NMC) battery. This is one of the most common lithium-ion battery technologies, and for a good reason: relative to other types of batteries, NMC batteries are known for their high energy density (the amount of energy they can store relative to the physical space they take up) and increased safety. To learn more about how different lithium-ion battery chemistries stack up against one another, check out our overview of battery chemistry differences.
Parts of a Tesla Powerwall
A Tesla Powerwall+ has four main components:
The Powerwall+ battery
A Tesla Gateway (Backup Gateway 2): controls the connection between the Powerwall system and the grid
Gateway meter: the gateway includes two internal meters, which your installer can configure to monitor different types of loads
Backup switch: a newer component of the Powerwall system for whole-home backup systems that facilitates backup power functionality when an outage is detected; must be approved by your utility
Tesla Solar Shutdown Device: a device required by the National Electric Code that is installed on the roof to permit rapid shutdown of the inverter for safety precautions
The Tesla app
Like other Tesla products (such as their solar panels, EVs, or EV charger), you can manage your Powerwall via the Tesla app. This app helps you easily monitor and manage your energy usage, customize preferences, see real-time metrics and stored energy amounts, control your Tesla Powerwall from anywhere, and get automatic notifications. Also, when paired with solar, you can use the mobile app to manage how you store excess energy.
Source: Tesla
There are several modes in the Tesla app to help you manage energy consumption with your Powerwall, including:
Backup Reserve mode
This allows you to manage your battery’s power output during an outage. If you prefer to reserve more energy in case of a power system outage, you can set a higher reserve percentage. You can also use your Powerwall as a backup-only appliance by selecting Self-Powered mode with a Backup Reserve of 100 percent, but this usually means you won’t save as much money, and you’ll increase your reliance on the grid.
A “Low Backup Reserve” indicator will display in the app if you set your reserve percentage below 20 percent. If this happens, your Powerwall may not have enough stored energy to provide backup support during an extended outage. So, suppose an outage or blackout occurs while your Powerwall’s stored energy is below five percent. In that case, you’ll immediately lose power, the Powerwall will save its energy, and it’ll recharge via your solar system the next morning.
Self-Powered mode
If your Powerwall is connected to solar, this option helps you increase your self-consumption of solar by storing it for use at night. Tesla Energy notes that this can almost double the amount of solar energy that powers your home. If you produce enough solar power to offset your home’s current energy needs and the Powerwall is fully charged, any excess solar power will be returned to the grid. Similarly, when your home uses more power than what’s available from your solar system and stored in your Powerwall, you’ll need to pull power from the grid.
Time-Based Control mode
If your utility has TOU rates, this option helps you save money by inputting the details of your utility rate plan.
Learn about all the energy management modes with the Tesla Powerwall.
Performance metrics
Two key ways to evaluate the performance of a solar battery are its depth of discharge and round trip efficiency.
Depth of discharge (DoD) indicates the percentage of a battery’s energy that has been discharged relative to the overall capacity of the battery. Because the useful life of a battery decreases each time you charge, discharge, and re-charge–or cycle–your battery, many manufacturers specify a maximum DoD level for optimal battery performance. Generally, batteries with a higher depth of discharge are considered better quality products. The Tesla Powerwall boasts a depth of discharge of 100 percent, reflective of its NMC battery chemistry.
Round trip efficiency measures electrical losses involved with charging and discharging a battery. The higher the efficiency percentage, the more efficiently the battery can convert incoming electricity into stored electricity and back into usable electricity. The Tesla Powerwall has a high round trip efficiency of 90 percent; this means that for every 10 kWh of electricity you put into the battery, you’ll receive 9 kWh of output.
How does Tesla Powerwall compare to other top batteries?
The Tesla Powerwall is hard to beat in terms of cost. But it certainly isn’t the only home energy storage system on the market with impressive specs. The Generac PWRCell and the Enphase IQ Battery are two other popular home batteries.
Tesla Powerwall versus the Generac PWRCell & Enphase IQ Battery 10 Generac PWRCell Enphase IQ Battery 10Tesla Powerwall Weight 287 pounds 341 pounds 251.3 pounds Warranty 10 years 10 years 10 years Size22 x 10 x 68 in42.13 x 26.14 x 12.56 in45.3 x 29.6 x 5.75 in Price$9,999 $18,000 $10,500 Storage Capacity 9+ kWh10.08 kWh13.5 kWh Continuous Power 3.4+ kW3.84 kW5.6 kW Peak Power6kW5kW10kW
See a detailed comparison of various battery options in our Best Solar Batteries Guide.
Tesla Powerwall warranty
A Tesla Powerwall+ and Powerwall warranty in the U.S. includes:
A 10-year warranty period: your Powerwall+ will be free from defects for 10 years following the initial installation date
An energy retention guarantee: your Powerwall+ will maintain at least 70 percent of its capacity to hold a charge throughout the warranty period for an unlimited number of cycles
If you have a Solar Shutdown Device(s) installed as part of your Powerwall+ system, Tesla guarantees it will be free from defects for 25 years following its initial installation date
Read our in-depth Tesla Powerwall warranty review for more information.
Most homes with a Tesla battery will charge and discharge their battery every day. Tesla’s battery technology is similar to other large and small rechargeable batteries: as time goes on, the battery loses some of its ability to hold a charge over its lifespan.
Think of how a brand-new smartphone’s battery life compares to a few years old: as you continually charge and drain your phone’s battery, it loses some of its ability to hold a charge. The life of your Powerwall battery will deteriorate in the same way. That isn’t an indicator of any product flaw. All batteries lose some of their ability to hold a charge over time after extended usage, whether it’s an electric vehicle battery, a home energy battery, or a rechargeable AA battery. This is why Tesla offers a warranty that guarantees a certain percentage of storage capacity for 10 years in the future.
If you want to compare individual battery models side-by-side, visit our Solar Batteries Buyer’s Guide to select products and compare them based on efficiency, capacity, power, and more.
Can you go off-grid with the Tesla Powerwall?
Installing a solar-plus-storage system at your home is a great way to take control of your electricity bill, but it doesn’t mean you’re completely disconnected from your utility. Going “off the grid” with solar batteries is more expensive and complicated than you might think. Most home batteries, including the Powerwall, only have enough capacity to store a few hours of electricity. If you want to make sure you can maintain power to your property for days at a time, you’ll need to install several Powerwall batteries together to increase your storage and usage capabilities.
Where to buy the Tesla Powerwall
The Tesla Powerwall battery is available online through Tesla’s website and by many solar and energy storage installation companies throughout the country. Adding energy storage technology to your home requires a trusted resource with electrical expertise, certifications, and knowledge of the best practices required to install a solar-plus-storage system correctly.
A qualified EnergySage-approved solar installer can give you the best recommendation about the Tesla home battery system or other energy storage options available. If you’re interested in seeing what you might save with solar and storage from installers near you, sign up for a free EnergySage Marketplace account today, and we’ll make it easy to compare options online.
storage content
This article was originally published on August 7, 2022, and has been updated.