A member of the LeafScore team had a Tesla Powerwall installed at his home in NY state. Here is a rundown of how much it cost, how solar incentives came into play, plus whether he recommends the Powerwall for your home.
Highlights: A top-of-the-line home solar battery that can be mounted both inside and outside.
The Tesla Powerwall is one of the most popular and sought-after solar batteries in the industry, with over a quarter of a million units installed across the country. In this article, I’m going to explain exactly what the Powerwall does, why you might want to consider buying one, how much it costs to install, and more.
- Cost of 2 Powerwalls: $17,650
- Cost with NY and Federal Solar Incentives: $11,680
- Helps keep the lights on in a blackout
- Expensive (especially without incentives)
- Can be mounted inside or outside your home
- Battery can be monitored with the Tesla app
What Is a Tesla Powerwall?
A Tesla Powerwall is a solar battery, which means it collects excess electricity produced by solar panels and stores it for later use. The Powerwall was first released in 2015, making it one of the first all-electric backup power options for residential solar customers in the U.S.
Two iterations of the original battery have been developed and released: the Powerwall 2, which was first offered in 2016, and the Powerwall +, which was released in 2021.
All models of the Powerwall can be mounted inside or outside your home, although many states have regulations that dictate which interior spaces can house solar batteries — inside attached garages are often the most popular interior mounting areas.
How Does the Tesla Powerwall Work?
The Powerwall acts as a backup generator, providing stored power to your home in the event of a blackout. That means you can maintain power even if your area loses electricity, and the switch to off-grid use is seamless. The battery can also be used to provide “backup solar energy” to power your home off-grid, even when the sun isn’t shining on your panels.
Importantly, if you only have solar panels installed on your home, you cannot “go off grid” and receive solar energy from the panels, even if they’re receiving ample sunlight. Allowing a panels-only setup to power your home in that case would put those working on power lines at risk of severe electric shock.
If you have panels and at least one Powerwall installed, you can run your home off of active solar energy being collected by your panels or with energy stored in your Powerwall that was collected when the sun was shining. Best of all, you never have to touch your Powerwalls; they offer power to your home automatically.
I should mention that you can use the Tesla app to monitor your battery charge, allocate the power in there for backup power during blackouts or for providing power when your panels aren’t producing, and keep an eye on usage over time. The app also shows information about your panel production and grid usage, providing an all-in-one solution for solar monitoring.
Tesla Powerwall Specifications
The table below includes some important Powerwall specs to keep in mind, as well as the industry standards for each for a quick comparison.
|Tesla Powerwall +||Industry Standard|
|Total Capacity||13.5 kWh||~8 kWh (6 to 14 kWh is standard)|
|Usable Capacity (Round Trip Efficiency)||12.15 kWh (90%)||90%|
|Depth of Discharge||100%||80% (80% to 90% is standard)|
|Average Power Output (Off-Grid)||7 kW||3 kW|
|Peak Power Output (Off-Grid)||10 kW||5 kW|
|Warranty||10 years||10 years|
|Cost||$11,500||$10,000 ($7,000 to $14,000 is standard)|
|Cost Per kWh of Storage||$851||$1,250|
*Please note: Most of the industry standards were established by reviewing the specifications of other popular solar battery options, including the Enphase IQ Battery 10, the Sonnen ECO, the EverReady Energy Vault, and more.
As you can see, the Powerwall’s specifications, especially in relation to its price, make it an above-average battery option overall. Tesla has been a leader in technological advances across several industries, so it’s unsurprising that it also excels in the solar industry.
How Much Does the Tesla Powerwall Cost?
I installed an 8.8 kW solar array on my home on Long Island in New York and coupled the SunPower panels with two Tesla Powerwalls — you can read about my experience with going solar here. We chose only to install two, given our relatively low energy needs.
The Powerwalls alone totaled $17,650 before any incentives. The first Powerwall was quoted at $11,500, and the second one was discounted because we installed multiple batteries.
We had them mounted inside our attached garage along with a Tesla Gateway and a data monitoring module.
Your pricing may vary depending on your installer and how many Powerwalls you install. As mentioned above, our second Powerwall was discounted, and we were told that additional discounts would be provided if we installed even more Powerwalls.
How to Save Money on the Tesla Powerwall
Although the Powerwalls I purchased totaled $17,650, I took advantage of two important solar incentives that brought the effective cost down to $11,680. I’ll list the incentives I took below and provide an explanation of how they affected my equipment costs.
- The Federal Solar Investment Tax Credit (ITC): The most significant incentive was the ITC, which is a 30% tax credit for all solar equipment, including batteries. That brought my price down from $17,650 to $12,355.
- The New York Solar Energy System Equipment Credit: This perk is specific to NY installations and may not be available to you. It’s a 25% tax credit (up to $5,000) for all solar equipment. This provided total savings on my entire system (panels + batteries) of $2,250. Since the batteries were approximately a third of my cost, I’m estimating that it saved me around $675 on the batteries alone, bringing my effective total cost down to $11,680.
I should note here that I typically owe quite a bit in income taxes, which is required to take full advantage of these incentives. If you don’t owe when it comes time to file your taxes, you might not see these same effective savings.
See also: NY state solar incentives
Additionally, the second incentive mentioned above is only available in NY, but you might have access to other state incentives. Below are some of the top state-specific incentives that could help reduce the effective cost of your Powerwalls:
- California’s Equity/Equity Resiliency Programs: Up to $1,000 in rebates per kWh of battery capacity you install
- Hawaii’s Renewable Energy Technologies Income Tax Credit: 35% tax credit up to $5,000
- Massachusetts’ Residential Renewable Energy Income Tax Credit: 15% tax credit up to $1,000
- New Mexico’s Solar Market Development Tax Credit: 10% tax credit up to $6,500
- New York’s Solar Energy System Equipment Credit: 25% tax credit up to $5,000
You can check the DSIRE database for more state-specific incentives that could help you save on Tesla Powerwalls and other solar batteries.
Do You Need Tesla Powerwalls? Why Did I Buy Them?
No, you absolutely do not need Tesla Powerwalls to enjoy the benefits of solar. Powerwalls and other solar batteries are expensive and, in my case, doubled the cost of my solar array. However, they provide a few key benefits, one of which can actually end up saving you money over time, depending on where you live.
Power During Blackouts
The first perk, which is obvious to most people, is that Powerwalls can store energy for your home that you can then pull from if the power goes out. That means you can maintain electricity even during blackouts, which is nice. Coupled with panels, you can also go entirely off-grid and recharge your batteries throughout the blackout for prolonged power.
This is a nice perk of solar batteries, but it usually isn’t enough to convince most solar customers to buy them.
Effective Net Metering
Here’s where Powerwalls can actually pay for themselves. Solar panels save you money by offsetting your electric bills, but they can’t offset your energy consumption at night or on cloudy days when they underproduce electricity. In areas without one-to-one net metering, this can severely limit your long-term energy savings.
Having Powerwalls — or other battery options — installed effectively lets you enjoy net metering. You don’t earn energy credits as you would in a standard net metering agreement, but you can store excess energy your panels produce for later use. That stored energy can offset consumption at night or during low-sun conditions. With Powerwalls, you can take full advantage of the sunlight available in your area and maximize your savings over time.
Wrapping Up: Why I’m Happy With My Tesla Powerwalls
Overall, I’m pleased with my decision to install Powerwalls alongside my panels. We’ve only had one blackout since the installation, but we maintained power with no interruptions at all.
We also have access to net metering in NY, so they’re not quite paying for themselves yet. However, the net metering policy is getting downgraded in the near future, as I expect it will in many other states as well. Plus, we’re planning on upgrading to electric vehicles, and it will be nice to charge them at night using our Powerwalls, something we’d need to pay retail rates for if we pulled that energy from the grid.
The Powerwalls were expensive, but we expect to get equal or greater value out of them in the future.
Highlights: A home solar battery that can be mounted both inside and outside.