In This Guide: Tesla Powerwall Cost | What is the Powerwall? | Specs and Features | How To Save | Conclusion | FAQs | Methodology
The Tesla Powerwall is one of the most popular solar batteries. It’s backed by one of the top solar energy companies and stores excess energy from your solar system to use at night, during power outages, or to offset high electricity costs. However, it comes with a hefty $14,200 price tag.
The This Old House Reviews Team has analyzed the Powerwall’s key features and specifications to determine if it’s worth the cost. This guide also provides saving tips for your installation.
- As of 2023, the Tesla Powerwall costs between $9,200 and $14,200 when buying directly from Tesla.
- In March 2023, Tesla announced the Powerwall Direct service, which offers standalone Powerwalls in select US markets.
- The Powerwall 2 and Powerwall+ share many functional similarities but differ in output performance and solar installation compatibility.
- Most homeowners only need one or two Powerwalls for energy backups, but require three or more to meet “off-grid” needs.
How Much Does the Tesla Powerwall Cost?
As of 2023, the Tesla Powerwall costs between $9,200 and $14,200 when purchased directly from Tesla. This pricing does not reflect additional state or federal incentives, such as the federal solar tax credit. Tesla offers purchasing options for inclusion with a solar panel or roofing system or as a standalone purchase.
Pricing With a Solar System
You can purchase a Powerwall with a Tesla solar system or solar roof. Pricing starts at $14,200 for one Powerwall. The price per unit decreases when you purchase more batteries and includes a limit of 10 units. For example, two Powerwalls cost $22,200, dropping the per unit price to $11,100. You’ll get additional discounts with three units for a total of $30,200. Most homes need only one or two batteries to meet their basic energy storage needs.
|Number of Powerwalls||Per-Unit Cost||Total Cost|
Pricing With Tesla Powerwall Direct
Tesla announced in March 2023 via social media that its new Powerwall Direct service allows customers to purchase standalone units in select US markets. These single Powerwalls start at $9,200, which breaks down to the following costs:
- $8,000 for the Powerwall
- $1,000 for Gateway Wi-Fi equipment
- $200 accessory fees
When ordering multiple standalone Powerwalls, the equipment and accessory fees remain the same, and you pay for another Powerwall unit only. Two Powerwalls cost $16,000, plus $1,200 for the additional equipment, totaling $17,200. Customers can order a maximum of three Powerwalls for $25,200. Orders also include a $200 delivery fee.
Your order comes directly to your home, but you must contact a Tesla Certified Installer in your area to schedule the installation. Currently, Powerwall Direct is limited in its availability. Customers can sign up for alerts when the service is available.
Pricing From Local Installer
If you don’t want to purchase directly through Tesla, you could purchase a Powerwall through a local certified Powerwall installer. This is a great option if you’re just looking for a new home battery to integrate into your solar system. The total cost for a Powerwall varies per installer and could range from $15,000–$18,000.
In addition to higher pricing, you’ll have a significantly longer wait time for your new Powerwall. Tesla prioritizes full solar system orders over individual battery orders. Placing an order through a third-party retailer will result in even longer delays since they have to get the products from Tesla.
Incentives and Rebates
When you purchase a Powerwall along with a Tesla solar system or as a standalone unit, you’re eligible for the federal solar tax credit. This provides a deduction equal to 30% of your solar panel costs on your federal income tax.
Based on our sample quote from Atlanta, Georgia, a 13.20 kW Tesla solar system costs $30,756, with an additional $14,200 for one Powerwall. The total system would cost $42,256, or $29,579, after applying the federal tax credit.
Using a sample quote for Austin, Texas, one standalone Powerwall totals $10,176 with all fees, delivery charges, and added sales tax. With the federal tax credit, your cost drops to $7,123.
You may also qualify for additional state and local credits, rebates, and incentives to reduce your solar panel and accessory costs. Check the Database of State Incentives for Renewables and Efficiency (DSIRE) for more information about incentives available in your state.
What Is the Tesla Powerwall?
The Powerwall is available in two models: The Powerwall 2 and the Powerwall+. Both models are available directly through Tesla’s website or sales department. You can purchase the Tesla Powerwall through third-party solar providers and certified Tesla installers.
Here’s a general overview of each Powerwall model:
- Powerwall 2: Released in 2016, the Powerwall 2 served as the newest version of the battery with twice the storage capacity. This version also includes a battery inverter/charger, which helps continuously charge the battery throughout the day.
- Powerwall+: The Powerwall+ was released in May 2021. This upgraded version of the Powerwall 2 includes an integrated solar inverter, making it easier to integrate into a new solar system.
Both batteries can store excess solar energy for later use, such as during low sunlight days, overnight, and during a blackout. A battery system offers energy independence from your power grid and provides additional home energy savings by allowing you to use all of the energy your system produces.
Features and Specifications
The Powerwall 2 and the Powerwall+ models share most features, such as energy storage capacity, but their power output and installation options differ. The Powerwall+ offers better power performance on full sun days than the Powerwall 2. In addition, the Powerwall 2 works with an existing solar system, while the Powerwall+ is made for new solar system installations. Here’s a side-by-side comparison of the Powerwall models below.
|Key Factor||Powerwall 2||Powerwall+|
|Storage capacity||13.5 kWh||13.5 kWh|
|Continuous power output (cloudy)||5.8 kW||5.8 kW|
|Continuous power output (full sun)||5.8 kW||7.6 kW|
|Peak power (cloudy)||10 kW||10 kW|
|Peak power (full sun)||10 kW||22 kW|
|Depth of discharge (DoD)||100%||100%|
|Round trip efficiency||90%||90%|
|Installation options||Works with existing solar systems||Works with new solar systems|
The Tesla Powerwall is a lithium-ion battery that uses lithium nickel manganese cobalt oxide (NMC) chemistry. NMC batteries are the most common type of solar battery. They have a solid lifespan of 10–12 years and high energy storage capacity, meaning they can store a significant amount of energy despite their smaller size.
Depth of Discharge
Depth of discharge (DoD) measures how much power you can draw from a battery before recharging efficiency drops. The industry standard is between 80% and 100%. Both Tesla Powerwall models have a 100% DoD, meaning you can charge the batteries to their full capacity every time.
Powerwall 2 can be added to existing systems that use several brand-name inverters, including Enphase, SolarEdge, and SMA. Tesla provides a full list of compatible inverters on its website. The Powerwall+ comes with its own dedicated inverter, making it a better choice for a new solar system.
Round-trip efficiency measures the amount of electricity that can be used after a full charge. According to the U.S. Energy Information Administration, the typical solar battery has a round-trip efficiency of 80%. The Tesla Powerwall offers an above-average round-trip efficiency of 90%, making it an efficient storage solution.
Pros and Cons
- Backup power customization: Homeowners can create customized energy storage options to meet their home’s energy needs.
- Durability: With added weather-resistant features and cold-weather functionality, the Powerwall performed well in both indoor and outdoor installations
- Energy independence: The Powerwall allows homeowners to generate and store their own electricity, reducing reliance on the electric grid and increasing energy independence.
- Multiple operating modes: You can choose from three energy consumption modes to improve your energy savings and lower your electric bill.
- Additional inverter for the Powerwall 2: The Powerwall 2 requires a separate solar inverter for installation with an existing system.
- Certified installer required: Powerwalls require a certified Tesla installer for proper installation.
- High cost: The Powerwall costs up to $14,200 for one battery, making it an expensive investment.
- Multiple Powerwall for off-grid homes: Homeowners need three or more Powerwalls to support off-grid homes, plus backup power options during low-sun months.
Who Is the Tesla Powerwall For?
With its large storage capacity and efficient power output, the Powerwall helps homeowners boost the effectiveness and cost-savings of their solar panel system. The Powerwall works well for customers looking for the following benefits:
- Energy independence: The Powerwall helps you store excess energy from your solar system, reducing your need for a grid-tied system. High-quality solar panels paired with a Powerwall eliminate wasted energy and better prepare you for emergency situations, such as blackouts.
- Reduced carbon footprint: Adding battery storage solutions improves clean energy use and reduces your need for costly fossil fuels. Relying on renewable energy sources reduces your carbon footprint and greenhouse gas emissions.
- Lowered electricity bill: The Tesla Powerwall lowers your electricity bill by tapping into more cost-saving solar energy. You have more options to power your home during the day and night, reducing your need for expensive electricity.
How Does the Powerwall Work?
The Powerwall stores excess energy from solar panels for future use. Batteries typically store direct current (DC) energy, the same type received through solar panels. However, your home appliances use alternating current (AC) to function. An inverter converts the DC power to AC power to use in your home. Excess AC energy flows to the backup battery to help it charge. The battery contains a rectifier that converts the energy back to DC power for storage.
The Powerwall 2 and the Powerwall+ include a builder-in inverter and rectifier to handle this energy conversion from storage to your home. The Powerwall 2’s inverter works for converting energy for the battery only. This model needs an external inverter for power conversion with solar panels. Since existing solar systems include a solar panel inverter, this model works well for the installation. The Powerwall+ comes with a solar inverter, eliminating the need to include one in a new solar installation.
Both Powerwall models include a liquid cooling system to regulate internal temperatures while performing. This system helps expel excess heat during heavy loading and rapid charging. The liquid thermal management system also protects the Powerwall’s performance during extreme weather conditions. The Powerwall can operate in temperatures ranging from minus 4 degrees to over 122 degrees Fahrenheit indoors and outdoors. This added protection helps extend the life span of your Powerwall.
The Powerwall continues to charge even in below-freezing conditions when faced with extremely cold temperatures. This below-freezing functionality is rare with lithium batteries, which don’t typically allow for charging below 5 degrees Celsius (41 degrees Fahrenheit). Its low weather performance is possible due to preconditioning, which reheats the battery cells to improve the charging capabilities and performance. The Powerwall switches to this mode automatically and uses grid power for preheating. During a blackout, the Powerwall uses its own stored energy to preheat cells. However, the battery must not be in a low-charge state.
Modes of Operation
The Powerwall includes three operating modes to manage and improve battery performance.
- Self-powered mode: The Powerwall will collect excess energy generated during the day and store it for use at night. The battery continues to charge until the capacity is reached. Any excess energy beyond this threshold is sent back to the power grid. This mode offers the best cost savings by effectively using your excess solar power generation.
- Backup reserve mode: This mode provides electricity to your home during power outages. The Powerwall automatically switches to this function when it detects no active power generation from your system. You can adjust the reserved percentage to allocate more or less stored power for future outages.
- Time-based control: This option pairs well with utility companies that use time-of-use electric pricing. Your time-of-use (TOU) rate fluctuates based on the time of day and power demand. The Powerwall charges during low TOU rate time periods and discharges energy when rates are high. This feature provides automatic savings throughout the year.
Parts of the Powerwall
Here’s an overview of a Powerwall’s basic parts.
- Powerwall battery: This rechargeable battery stores your excess energy.
- Tesla Gateway (Backup Gateway 2): This device regulates your solar system’s grid connection and monitors for outages, tracks energy use, and controls backup power functions. The Backup Gateway 2 is the latest version used in the Powerwall 2 and Powerwall+.
- Gateway meters: The Powerwall contains two internal meters to regulate power charging and distribution to and from your solar and grid systems.
- Backup switch: The component works with the backup power features and detects power outages. The feature works with whole-home backup configurations and requires approval from your utility company.
- Tesla solar shutdown device: This safety device installs on your roof and provides immediate inverter shutdowns as a safety precaution. The National Electric Code, issued by the National Fire Protection Association, requires this device.
How Many Powerwalls Do I Need?
The Powerwall provides a full day of battery backup during cloudy or winter days. Its capacity extends to 2.5 days on a sunny day or during the summer. Installing two batteries increases capacity to 1.5 days in cloudy conditions and more than seven days with full sun exposure. The battery can provide electricity to most 120-volt appliances and electric outlets. However, higher-powered systems, such as air-conditioners, would require additional Powerwalls.
The Powerwall functions as a whole-home or partial backup system, depending on your power needs. We’ve provided an overview below of each configuration:
- Whole-house backup: This configuration provides power to your whole home during a power outage. If you have several high-power appliances, your battery life will reduce more quickly. This setup is best for homeowners living in areas with inclement weather that causes blackouts. You should also consider this option if you want backup power for your home and can afford multiple Powerwalls. Most homes will need three or more Powerwalls for adequate power backup.
- Partial-home backup: With a partial backup option, your Powerwall only supplies power to essential appliances during a power outage. For instance, you’d supply energy to only your HVAC system, refrigerator, or other necessary components. Homeowners should consider this configuration if they want to keep their investment to a minimum and focus on essential appliances only. For this setup, you’ll need only one or two Powerwalls during emergencies.
How Much Space Does the Powerwall Need?
The Powerwall works in both indoor and outdoor installations thanks to its weather-resistant design. You’ll need adequate space for the full Powerwall system, including the battery and gateway box. The Powerwall battery requires 4 by 5 feet of space with 6 feet of clearance in the front. To function, the gateway box needs a 2-by-3-foot space and a solid Wi-Fi signal. The gateway connects via Wi-Fi or ethernet cable.
Lifespan and Warranty
Both Powerwall models come with an industry-standard 10-year warranty. The warranty guarantees unlimited charge cycles for the full coverage length. This coverage exceeds many other batteries, which include warranty coverage for a certain number of years or limited cycle clauses, whichever comes first. Tesla includes a four-year workmanship warranty that covers any replacements or repairs due to poor installation. This also covers the shipping for any necessary replacement parts.
The warranty also states that the Powerwall will have an end-of-life capacity of 70% when used in self-consumption or backup modes. Due to more frequent charging cycles, this percentage could drop with other modes, such as the time-based control mode. This clause means the Powerwall provides at least 70% of its original 13.5 kWh capacity. This is higher than the average end-of-warranty capacity of around 60%. Your Powerwall may function longer than the 10-year coverage, but capacity will continue to reduce.
The Powerwall does have off-grid capabilities but under certain circumstances. Originally, the
Powerwall was designed to function as a grid-tied storage system with short-term backup capabilities. Its purpose was not for off-grid system support. To use the Powerwall for off-grid purposes, the system must be installed in a protected location and connected to solar panels efficiently enough to support your home.
Typical off-grid homes need an average of 7 kW–10 kW of solar power. The Powerwall supplies 5 kW of power, so you’ll need multiple batteries. You’ll need three or more Powerwalls to provide ample backup to your home. Homeowners should also invest in an additional backup power source to support energy production during cloudy winter months.
If you’re considering using Powerwalls for your off-grid home, we recommend reviewing a detailed guide on proper off-grid home configurations.
The Tesla App
The Tesla App provides customers with a user-friendly interface that gives complete control over their Powerwall battery. Homeowners can change Powerwall’s mode of operation between backup, self-powered, and time-based controls right from their phone. The app also offers a Storm Watch feature which receives updates from the National Weather Service concerning potential backouts and inclement weather. In the event of a power outage, this mode activates battery charging to prepare for any power outages.
The app also provides energy use monitoring, real-time metrics, and stored energy levels on your battery. When paired with your solar system, you can regulate home energy storage options and capacity.
Compare Tesla Powerwall to Other Solar Batteries
Here’s a comparison of the Powerwall to other top solar batteries on the market.
|Measurement||Powerwall 2||Powerwall+||Sonnen Eco||Enphase IQ||SunPower SunVault|
|Cost||$9,200–$14,200||$9,200–$14,200||$10,000+||$5,000–$10,000||Price by quote only|
|Storage Capacity||13.5 kWh||13.5 kWh||5 kWh–20 kWh||3.36 kWh–10.08 kWh||12 kWh–24kWh|
|Continuous Power Output||5.8 kW||5.8 kW–7.6 kW||3 kW–8kW||1.28 kW–3.84 kW||6.8 kW–8 kW|
|Depth of Discharge (DoD)||100%||100%||90%||100%||Not disclosed|
|Round Trip Efficiency||90%||90%||90%||96%||85%|
|Warranty||10 years||10 years||10 years or 10,000 cycles||10 years or 4,000 cycles||10 years or 4,000 cycles|
|Our Rating||95 of out 100||95 of out 100||97 out of 100||96 out of 100||93 out of 100|
Our Conclusion: Is the Tesla Powerwall Worth It?
The Powerwall offers high power capacity, cost-saving operating modes, and excellent backup capabilities. The Powerwall+ offers better performance during sunny days and integrates well into new solar systems. With the Powerwall 2, homeowners can boost their existing solar installation with additional energy storage options. Homeowners can purchase multiple Powerwalls to provide adequate power for whole- or partial-home backups, giving more flexibility to their energy storage needs.
FAQ About Tesla Powerwall
Our Rating Methodology
The This Old House Reviews Team aims to provide comprehensive and unbiased reviews to our readers. This means earning your trust through transparent reviews and data to back up our recommendations. Our rating system for solar batteries is on a 100-point scale based on five factors:
- Depth of discharge (20 points): Does the company disclose its depth of discharge (DoD) rating? Does the DoD meet the industry standard of 80%? The higher the rating, the higher the score.
- Round-trip efficiency (20 points): How efficient is the battery? Does it meet or exceed the industry standard of 80%? The higher the round-trip efficiency, the more points we awarded.
- Battery chemistry (15 points): We awarded more points to Lithium Iron Phosphate (LFP) batteries than Lithium Nickel Manganese Cobalt Oxide (NMC) batteries due to their higher efficiency and longer lifespan.
- Battery options (15 points): We awarded more points to brands with multiple battery sizes for better customization, rather than only one size.
- End-of-warranty capacity (15 points): How powerful will the battery be at the end of its warranty? Does the projected end-of-warranty capacity meet the industry standard of 60%? We awarded more points to batteries with higher end-of-warranty capacities.
- Warranty length (15 points): How long is the battery’s warranty? Does it meet or exceed the standard 10-year warranty? Batteries with the longest, most comprehensive warranties ranked higher.
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