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 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 $11,500 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.

 


 

How Much Does the Tesla Powerwall Cost?

The Tesla Powerwall battery costs $11,500–$80,500, depending on the number of batteries installed. Below is a breakdown of the Powerwall costs:

Number of Powerwalls InstalledTotal Cost
1$11,500
2$18,500
3$25,500
4$32,500
5$40,500
6$48,500
7$56,500
8$64,500
9$72,500
10$80,500

The price of individual Powerwalls decreases as you add more batteries to your system. A single Powerwall battery costs $11,500. The cost for two Powerwalls drops to $18,500, or $9,250 per battery. This tiered pricing continues through the largest configuration possible: 10 Powerwall units for $80,500. 

It should be noted that Tesla doesn’t sell the Powerwall separately. You must purchase a full Tesla solar power system and add the Powerwall to your order. You can install a traditional rooftop solar panel system or one of Tesla’s solar roofs. The pricing for these services varies, but you can expect to pay an additional $20,000 or more for solar panels

Tesla also has considerable wait times for solar panel installations. It may be several months before your solar system is installed with your Powerwall batteries. Placing an order through a third-party retailer will result in even longer delays since they have to get the products from Tesla.

 

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What Is the Tesla Powerwall?

The Powerwall was introduced in 2015 to complement Tesla’s growing developments in solar technology. It’s since become one of the top residential solar batteries. 

The Powerwall is available in two models: The Powerwall 2 and the Powerwall+. Both batteries can store excess solar energy for later use, including during low sunlight days, overnight, and during a blackout. A battery storage 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. 

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.

Tesla Powerwall Specs and Features

The Powerwall 2 and the Powerwall+ models have many of the same features but are suited for different solar installations. We’ll highlight some of the main differences between the models below.

Battery Capacity

Both Powerwall models have a stored energy capacity of 13.5 kilowatt-hours (kWh), but their storage capabilities depend on how much sunlight your panels receive on a typical day.  The Powerwall can provide 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. 

You can add up to 10 batteries to your home, but one to two batteries should be enough to meet most homeowners’ energy needs. You’ll need two or more Powerwall batteries to go off-grid altogether. 

Chemistry

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

Solar batteries are made to be charged and recharged, but their efficiency can decrease the more the battery is drained. Depth of discharge (DoD) measures how much power you can draw from a battery before the lifespan is impacted.

Many battery manufacturers limit DoD to preserve battery life. 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. 

Power Output

The Powerwall models’ power output differs based on ideal weather conditions. The Powerwall 2 provides 5.8 kW of continuous power and 10 kW of peak power. The Powerwall+ provides the same amount of power under no-sun conditions, but its full sun capabilities are much higher, with 7.6 kW continuous power and 22 kW peak power.

Continuous power measures how much power can be released from a solar battery over a certain period. Batteries typically run at lower capacities to provide power for longer. Peak power measures the highest burst of energy that a battery can provide, such as during a blackout. A battery with high peak power can expel a large amount of energy in a short period.

Round-trip Efficiency

A small percentage of power is needed to run the battery itself, so you won’t be able to tap into 100% of the energy every time. 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. 

System Compatibility

The Powerwall 2 is made to work with existing solar systems with third-party solar inverters. An inverter converts the direct current (DC) power received from the sun into alternating current (AC) power to use in your home. The Powerwall 2 can be added to 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 best for a new solar system. 

Warranty

Both Powerwall models come with an industry-standard 10-year warranty. Tesla includes a four-year workmanship warranty that covers any replacements or repairs due to a poor installation. This also covers the shipping for any necessary replacement parts. Tesla states that the Powerwall will have an end-of-warranty capacity of 70% of its 13.5 kWh capacity. The average end-of-warranty capacity is around 60%.

 


 

How To Save On the Tesla Powerwall

When you purchase a Powerwall along with a Tesla solar system, you’re eligible for the federal solar tax credit. This provides a deduction equal to 30% of your installation costs on your federal income tax.

Based on our sample quote, a 7.2 kW Tesla solar system costs $14,471, with an additional $11,500 for one Powerwall. The total system would cost $25,971, or $18,180, after applying the federal tax credit. 

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.

 


 

Our Conclusion

Having a solar battery can lower your electricity bill and keep your home powered during a blackout. The Powerwall is a standout option thanks to its high power capacity, excellent DoD, and efficient power cycling. However, it requires a higher investment in a complete Tesla solar panel system if you can’t find a third-party seller in your area. 

Use the tool below to find a Tesla dealer or certified Tesla installer nearby.

 


 

FAQs 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.

To share feedback or ask a question about this article, send a note to our Reviews team at reviews@thisoldhousereviews.com.