Note: In July 2024, SunPower notified dealers it would be halting all new shipments and project installations. The company also noted it would “no longer be supporting new Leases and PPA sales nor new project installations of these financing options.”
The Tesla Powerwall is one of the best solar batteries in the solar industry, but is it worth the hype? In this Tesla Powerwall review, I’m going to discuss all you need to know about the Powerwall. I’ve spent years researching and writing about solar equipment, and I also have two Powerwalls installed in my own garage, so I’ll draw on both professional and personal experience to provide you with the most complete information possible in this Tesla Powerwall review.
Before I dive into my experience and review, I should note that Tesla is a manufacturer only, and it doesn’t have an in-house installation team. Instead, it uses third-party installers to tackle the installation for it. You can choose from one of Tesla’s certified installers below to get panels, Powerwalls, EV chargers, and even solar roofs from the company installed in your home.
4.3
No payments needed for 18 months
Provides in-house financing
Offers top brands like LG and Trina
3.9
Highly rated customer service
Provides 24/7 panel monitoring
Solid A+ rating with the BBB
3.7
Affordable prices
Excellent selection of panels and services
Locations in 22 states
My Take on the Tesla Powerwall
In my opinion, the Tesla Powerwall is the best solar battery you can buy, not only because of the capacity but also because it works seamlessly with the Tesla app, gives you total control over how your energy is stored and used, and has a higher power output to help support your energy needs, even if they’re above average.
The Tesla Powerwall is sleek and modern, and it’s super silent. Even when I’m in my garage, and they’re running to provide power to my house, I can barely hear them.
Overall, I think they provide tons of value, and they should boost your home value as well, which is an added bonus.
What I Like About Tesla Powerwalls
Honestly, I like pretty much everything about the Powerwalls I have. The primary thing I use them for is backup power during blackouts, and for that purpose, they’re incredible. They take your home off-grid and maintain power seamlessly without any interruption to electricity, and they even monitor local weather conditions and charge themselves to full capacity in preparation for major storms through a feature called Storm Watch.
Powerwalls are also one of the best battery options for saving money, in my opinion, if you don’t have access to a one-to-one net metering program. They have a capacity of 13.5 kilowatt-hours (kWh), which is higher than most. That means they store more solar energy for use when your panels aren’t in full sun and aren’t producing sufficient power.
If you don’t have net metering in your area and your energy rates and consumption are average, the Powerwall should pay for itself in around 11 years.
Drawbacks of Tesla Powerwalls
There are two main drawbacks to the Tesla Powerwall, in my opinion. The first is that the cost per powerwall battery, at an average of $11,500, is quite high. You can effectively bring this down by taking advantage of the federal investment tax credit (ITC) and the rebate Tesla is currently offering on its Powerwalls. Still, if you just want a small battery system for emergency backup power only, this isn’t the best option.
The other downside is that the Powerwall is the most popular solar battery in the country, and production is struggling to keep up with demand. My Powerwalls weren’t available until about six months after my panels were installed, even though everything was ordered at the same time. Expect to wait a few months for your batteries, and keep in mind that you may not see the same savings during that time period as you would if your batteries were available right away.
What Is the Tesla Powerwall?
The Tesla Powerwall is a home battery that operates like an electric generator if you install it alongside solar panels. Basically, it’s a high-performance, high-capacity battery that stores solar power collected by your panels and saves it for when you need it. You can use that stored energy to offset your energy bills if you don’t have access to a good net metering policy, or you can use it to maintain electricity during power outages.
There are currently two Powerwall models available: the Powerwall — technically the Powerwall 2, as the original is no longer available — and the Powerwall+.
The standard Powerwall doesn’t include a solar inverter, so you can install it in your home as a standalone battery or couple it with an existing solar system that already has an inverter. The Powerwall+ includes an inverter and is a better option if you’re going solar through Tesla — remember, that really means through a certified Tesla Energy installer.
The Tesla Powerwall 3 is currently being teased and isn’t even listed on the Tesla website yet, but there are only a few details available for it so far. The table below includes a quick look at how the three models compare.
Models | Tesla Powerwall 2 | Tesla Powerwall+ | Tesla Powerwall 3* |
Total Cost | $11,500 | $11,500 | Not available |
Capacity | 13.5 kWh (kilowatt-hours) | 13.5 kWh | 16 – 20 kWh |
Dimensions | 45.3” x 29.6” x 5.75” | 62.8” x 29.7” x 6.3” | Not available |
Weight | 251.3 lbs. | 343.9 lbs. | Not available |
Battery Type | Lithium-ion | Lithium-ion | Lithium-ion |
Mounting Options | Ground or wall, including stacked | Ground or wall, including stacked | Ground or wall, including stacked |
Lifespan | 10+ years | 10+ years | 10+ years |
Warranty | 10 years | 10 years | Not available |
Tesla Powerwall 2
The Tesla Powerwall 2 is just a battery without the inverter that comes with the Powerwall+. It has roughly the same performance specs as the Powerwall+, although it’s lighter and a bit smaller. The cost is around the same as well. The main difference is that you can install the Powerwall 2 with a non-Tesla solar array, and you can even install it without a solar array at all via Tesla’s Powerwall Direct process.
Tesla Powerwall+
The Powerwall+ has similar specs to the Powerwall 2, although the inverter adds to the size and weight of the battery. Again, the primary difference between this and the Powerwall 2 is the inclusion of a Tesla inverter, so the Powerwall+ is probably a more appropriate option if you’re going solar through Tesla. If you’re adding a battery to a home without solar or with solar already installed, the Powerwall 2 is going to suit you better.
Tesla Powerwall 3
The Powerwall 3 hasn’t been released yet, but it’s expected sometime soon. The only real information we have about the Powerwall 3 so far is that the continuous power output is a massive 11.5 kW (kilowatts), which is around 50% higher than the Powerwall 2 and the Powerwall+. That means it will be able to support a higher consumption of energy while your home is off-grid.
There is also some speculation that the storage capacity will be getting a similar upgrade, which would put the total capacity between 16 and 20 kWh and make the Powerwall 3 one of the largest batteries in the industry.
You can check out the video below for a look at the new Powerwall 3 prospects and what experts are expecting from this new iteration:
Who Is the Tesla Powerwall Designed For?
The Tesla Powerwall is designed for homeowners with and without solar panel systems alike that are looking to maintain power for their homes during blackouts and maximize solar savings. There are many reasons why you might consider installing Tesla Powerwalls in your home:
- Better preparedness for natural disasters and storms
- Maintain emergency power at all times
- Maximize solar savings if you don’t have retail net metering
- Peace of mind if you rely on power for medical equipment
- Increases your home value
- Can reduce fueling costs for electric vehicles (EVs)
- Provides total control over your panels and battery storage system
You can use the tool below to get connected with a certified Tesla installer in your area to get your hands on Tesla Powerwalls and other solar equipment.
How Do Tesla Powerwall Batteries Work?
The exact function of a solar battery varies based on its unique design, but for the most part, batteries feature the same working process. The purpose is to store excess renewable energy that your solar panels produce for future use, such as during a power outage.
Generally, batteries store direct current (DC) energy, but the appliances in your home utilize alternating current (AC) energy. To accommodate the difference, the Tesla Powerwall+ comes with an inverter and rectifier to convert stored power into usable energy for your home, and the standard Powerwall will use the inverter installed with your solar system (if installed separately).
During the day, your solar panels absorb energy from the sunlight streaming down on them. The excess energy your panels produce heads to the Tesla Powerwall, where it remains in storage. About 90% of the energy that travels to the battery makes it, while 10% is lost during the journey, which is a solid ratio.
Once the energy reaches the battery, it remains stored there until you need it. For example, if your area experiences a power outage, your battery can supply energy to run the necessities in your home.
One additional thing to mention is that the Powerwall includes an islanding inverter or uses the islanding inverter that came with your panels, if applicable. That means it can receive power from your panels and recharge even during blackout conditions. Some batteries don’t offer this. This is huge because it means you can last much longer during blackout conditions. My batteries would normally deplete in about a week with normal usage during a blackout, but with the islanding inverter, I still had over 98% energy capacity after a few days of not being on-grid.
You can check out the video below for a brief explanation of how the Powerwall works to power your home:
Operating Modes of a Powerwall
When you need power from the battery, the inverter converts it to power your home appliances can use, ensuring you have the energy you need when you need it. The battery features three operating modes:
- Backup power: This mode uses the Powerwall as a source of energy in emergency situations such as blackouts.
- Solar charging and use: In this mode, the sunlight is streaming down in full force, and your solar setup is powering your home and charging the Powerwall. The energy sent to the battery is stored for future use, like on cloudy days or during the night.
- Time-based control mode: In this mode, your Powerwall will collect electricity from the grid when the cost is the lowest, ensuring you save money — the maximum amount — on your utility bills. It’s an ideal option for people living in areas where energy costs fluctuate throughout the day.
Components of a Tesla Powerwall System
The Tesla Powerwall system consists of just a few components:
- Battery: Of course, the battery is the main part of the system. This gets mounted inside or outside your home, either on the ground or on the wall. This is the component that stores the energy for your home.
- Inverter: The inverter in the Tesla Powerwall system converts DC energy collected by your panels to AC energy for use inside your home. This is also an islanding inverter, which means the batteries can be charged via your solar panels even during a blackout. If you purchase the standard Powerwall without a built-in inverter, you’ll need to rely on the inverter or microinverters that came with your solar panels.
- Controller: The controller is a small computer that controls how and when your batteries charge and discharge. The controller also connects to the internet, making features like Storm Watch possible and allowing you to interface with your batteries via the Tesla app.
- Emergency exterior shut-off: All battery and battery-and-panel systems must have an emergency shut-off switch installed on the exterior of your property so that it’s accessible even when you’re not home.
Control Your Powerwall with the Tesla App
The Tesla app is available for free on most smartphones, and your solar company should sync your system with the account you create. The app gives you live-time information about and control over your solar system, as well as your Tesla car and EV charger if you have those as well.
As far as the Powerwall goes, there are three important features to understand:
- Storm Watch: Storm Watch is one of the coolest features of the Powerwall, in my opinion. Your battery stays connected to the internet and monitors the weather in your area. When there’s a storm or natural disaster headed your way, the battery will override your programmed settings and store as much energy as possible to prepare for a blackout. This maximizes your energy availability during emergency situations, and it’s all done without any input from you. You even get notifications when your battery detects an incoming storm.
- Battery allocation: You can access a slider in the app to control what percentage of your battery is allocated toward storing energy for blackouts and what percentage is allocated toward offsetting how much grid power you pull. This is an exceptional feature for homeowners who have a time-of-use energy plan. Basically, your battery can automatically store energy when power is cheapest and discharge when it’s most expensive to maximize your energy savings.
- Energy data: Finally, the Tesla app gives you real-time data about the energy stored in your battery, the power coming from your panels, and the electricity you pull from the grid. You can even see how self-sufficient you are over time, as well as the effects changes you make have on your savings, self-consumption, and your energy independence.
Tesla Powerwall Specs
The Tesla Powerwall is one of the more powerful solar batteries out there, so the specifications are pretty impressive. I’ll include the important specs in the table below and then explain some of the more complicated ones and how they affect the user experience.
Per-Battery Capacity | 13.5 kWh |
Max Capacity | 135 kWh |
Continuous Power Output | 5 kW |
Peak Power Output | 7 kW |
Depth of Discharge | 100% |
Round Trip Efficiency | 90% |
Percentage Remaining at 10 Years | 70% |
Since some of these specs might be new to you, I’ll explain what each one is and why it’s important below.
- Per-battery capacity: This is the storage capacity of each Powerwall you install. A high capacity like the Powerwall has means each battery can store more power for your home, which means a longer time you can last without electricity during a blackout. The Powerwall has one of the highest per-battery capacities available.
- Max capacity: This refers to the total home energy storage you can have if you connect multiple batteries in series. A high max capacity means you can continue to power your home for weeks through just about any blackout you might experience. The Powerwall has one of the highest max capacity specs in the industry.
- Continuous power output: This refers to how much power your battery can discharge continuously without getting damaged. Higher continuous power output means you can pull more electricity during a power outage, so higher numbers here are ideal for large homes, large families, or families that consume a lot of electricity. The Powerwall is just slightly above average in terms of continuous power output.
- Peak power output: Peak power output is similar, but it refers to the maximum rate of discharge your batteries can handle without sustaining damage. This is a less useful metric, but if you have sudden surges of energy consumption, a higher number here means more peace of mind that your battery can handle it. The Powerwall is a little below average in this regard, with most batteries sitting at 7.5 kW or higher.
- Depth of discharge: Depth of discharge or DoD is how much of your battery’s total capacity can be discharged. Most batteries can’t be entirely depleted without being damaged, which effectively limits the usable capacity. The Powerwall can be 100% discharged, making it one of the best batteries in the industry in regards to this metric.
- Round trip efficiency: This refers to how much energy is lost between the time electricity is pumped into the battery and when it’s pulled out for use in your home. A higher round trip efficiency means less energy is lost over time, which maximizes how much you can use in your home and helps increase your energy savings as well. The Powerwall has a 90% round trip efficiency, which is above average and close to the best in the industry.
- Percentage remaining: All batteries degrade and lose storage capability over time. This metric tells you how much of the original percentage will remain after 10 years (the typical battery warranty term). The higher this number, the more usable life you’ll get out of your batteries. The Powerwall is just a little below average in this category, although 70% after 10 years is still quite impressive.
Tesla Powerwall Lifespan & Warranty
The Tesla Powerwall includes a 10-year warranty, which is in line with the industry average. If your batteries fail within that time or lose more storage capability than expected — a maximum of 30% over those 10 years — then Tesla will step in to repair or replace the battery. Based on my research, very few people have had to make a warranty claim, so the Powerwall seems to be holding up well.
I say “seems to be” because solar storage is a relatively new concept. The Powerwall was the first majorly popular solar battery offered for residential use, and it was only released in 2015 and then mass-produced starting in 2017. That means none of the Powerwalls installed in residences have reached their expected end of life.
In my opinion, Powerwalls will probably last for 15 to 20 years before needing to be replaced. The 10-year warranty might make you question that, but I saw something similar with solar panels. Many manufacturers originally offered a 15-year warranty, which was bumped to 25 years when those original panels were still producing sufficient power beyond the warranty.
Maxeon just recently increased its warranty to 40 years. Why? Because most of the panels that were installed 30-plus years ago are still working today. My guess is that Tesla went conservative on the battery warranty, much like panel manufacturers did decades ago, and the batteries will actually last significantly longer than the 10-year warranty.
Compare the Tesla Powerwall vs. Other Solar Batteries
I believe the Powerwall holds up to the hype, as it’s one of the most technically advanced solar batteries available across a handful of the most important battery specifications. I wouldn’t have installed two Powerwalls in my own home if I didn’t firmly believe that.
I’ll include a table below to show you how the Powerwall stands up to some of the competition. You’ll see that some batteries outperform the Powerwall in certain specs, but when considered together, I think Tesla’s product is the most impressive.
Battery | Tesla Powerwall | SunPower SunVault | Panasonic EverVolt | LG Prime | Generac PWRcell | Enphase IQ |
Per-Battery Capacity | 13.5 kWh | 13 kWh up to 52 kWh | 17.5 kWh | 9.8 kWh | 9 kWh up to 18 kWh | 10.5 kWh |
Max Capacity | 135 kWh | 52 kWh | 102 kWh | 19.6 kWh | 36 kWh | 40 kWh |
Continuous Power Output | 5 kW | 6.8 kW | 9.6 kW | 5 kW | 8 kW | 3.8 kW |
Peak Power Output | 7 kW | 10 kW | 12 kW | 7 kW | 10 kW | 5.76 kW |
Depth of Discharge | 100% | N/A | 100% | 90% | 84% | 95% |
Round Trip Efficiency | 90% | 85% | 90% | 90% | 84% | 96% |
Warranty Term | 10 years | 10 years | 10 years | 10 years | 10 years | 10 years |
Percentage Remaining at 10 Years | 70% | 70% | 60% | 60% | 70% | 80% |
Weight | 251.3 lbs. | 270 lbs. | 133 lbs. | 165 lbs. | 287 lbs. | 346 lbs. |
Incentives Apply | Yes | Yes | Yes | Yes | Yes | Yes |
Bottom Line: Should You Buy a Tesla Powerwall?
Ultimately, whether or not you should buy a solar battery in general depends on the benefits it will provide in your specific situation — if you live in an area where blackouts are common and you want or need to avoid them, or if you live in an area where net metering isn’t available, then a solar battery is probably a good idea. And if you’re going to invest in a solar battery, I would strongly recommend the Powerwall over any other option.
Tesla Powerwalls have a lot of hype around them, but I feel the product is deserving of all of the attention and praise. The specs alone make the Powerwall one of the best solar batteries you can buy and the most likely to maximize your energy savings. The convenience of interfacing with the battery via Tesla’s mobile app also makes it a great option.
Also, if you’re like me and see the immense value you can get from a Powerwall, you can use the tool below to be connected with a certified Tesla solar installer in your area.
Read also: States with the Highest Solar Panel Productivity
I get more questions about the Powerwall than any other battery on the market. Below, I’ll answer some of the most common questions I see.
FAQs About the Tesla Powerwall
Will 2 Tesla Powerwalls run an air conditioner?
The answer to this question depends on many factors, including the size of your AC system, what other loads you’re putting on the batteries, and how long you want to run your AC off-grid, but in most cases, yes, two Powerwalls will run a central AC or ductless mini splits with no issue at all. The average central AC system uses around 3,000 watts per hour, which means two Powerwalls — with a total capacity of 27,000 watts — could run the system for around nine hours. Keep in mind that your panels could recharge your batteries during that time period, extending how long you can be self-powered — sometimes indefinitely.
How long will the Tesla Powerwall power a house?
It depends on many factors, like how much energy your home consumes, how many Powerwalls you have installed, and more, but the average Powerwall can power a house for half a day with no additional input of energy. This assumes the typical consumption of 30 kWh per day. If you have solar panels installed as well, they can recharge your batteries during a power outage, thanks to the islanding inverter in the Powerwall. That means your Powerwall could last through the night on its own and then get recharged during the day, all while providing seamless energy to your home.
How many Powerwalls do I need to go off-grid?
The number of Powerwalls you need to go off-grid depends on your average daily energy consumption and whether or not you have panels installed as well, but most homes can get by with emergency power — lights and refrigerator — with one Powerwall, and enjoy normal energy usage — lights, fridge, AC, heat, and other appliances — with two to three Powerwalls. You can go off-grid with just one Powerwall, but you’ll need multiple ones if you want to use electricity as you normally would. Panels will recharge your batteries during the day, so homeowners with panels and Powerwalls can often go off-grid with just two Powerwalls.
Is the Tesla Powerwall the best solar battery available?
Most people agree that the Powerwall is the best solar battery available, and the specifications certainly back that up. The Powerwall has one of the highest per-battery and total capacities available, it has a 100% depth of discharge, a high power output to meet most people’s energy demands, and comes with the Tesla app, which gives you total control over how your energy gets stored and used to save you money on your electricity bills. While it’s expensive, it actually has a below-average per-kWh cost, making it an overall outstanding value.
Methodology: How We Reviewed the Tesla Powerwall
At Today’s Homeowner, we always do extensive research and lean heavily on personal experience to bring you the best information available. I’ve done years of continued research on solar batteries and have installed Powerwalls in my own home, so I feel this is the most complete Tesla Powerwall review possible. Today’s Homeowner’s ratings are all made available publicly so that you can see exactly how the Powerwall and other batteries are reviewed. I’ll include a breakdown of the scoring below.
- Battery Capacity (20 points): First, I considered the per-battery capacity, which tells you the maximum storage available. Ultimately, a higher battery capacity means each battery can power your home for longer in an outage. The Powerwall has one of the highest capacities in the industry at 13.5 kWh, making it an absolute powerhouse.
- Battery Chemistry (15 points): There are a few different kinds of batteries available, but lithium-ion batteries are considered the best because they work well for heavy loads, need basically no maintenance, and lose efficiency slowly compared to other options. The Tesla Powerwall is a lithium-ion battery, and an advanced one at that.
- Depth of Discharge (20 points): Lots of batteries will get damaged if you deplete their energy storage entirely, which means the amount of available electricity you have in a blackout is limited with a lower depth of discharge (DoD). The Powerwall is one of the few batteries that has a 100% DoD, so you get to use the entire capacity during a power outage.
- Round Trip Efficiency (20 points): Batteries with a higher round trip efficiency will lose less of the energy your panels or the grid put into them, so a higher number here means more efficient batteries and, consequently, greater energy savings over time. The Powerwall has an impressive 90% round trip efficiency. It’s not the best in the industry, but it’s around average. The best options have a 96% round trip efficiency.
- Off-grid applications (5 points): Batteries are designed to provide the convenience of electricity in power outages and peace of mind in emergency situations, and some do that better than others by offering more off-grid applications. The Powerwall not only lets you control your storage and consumption remotely to conserve during outages, but it also includes an islanding inverter, so you can recharge your batteries with your solar panels while you’re off-grid.
- Warranty length (10 points): Solar battery tech is fairly new and quite expensive, which means a solid warranty is necessary for peace of mind and for ensuring that your investment is a good one. The industry standard is 10 years, which is what the Powerwall warranty is.
- End of warranty capacity (10 points): All batteries lose efficiency and storage capacity over time, and the end of warranty capacity tells you how quickly your battery will degrade. A higher capacity means your battery will last longer and continue to provide more value as time goes on. The Powerwall has an end-of-warranty capacity of 70%, which is about average.
We monitor company data on an ongoing basis to keep rankings and information up to date.