Tesla is primarily known for its electric vehicles, but they also make solar panels. Once installed, they can provide power for an entire home, but you'll want a battery to store all that power. The Tesla Powerwall is the battery that stores this power and makes it readily available when required.
Utilizing solar power in a home has various advantages including being both free and better for the environment. Keeping a full battery in your home also provides a backup power source in case of outages.
So how does the Tesla Powerwall work and how much does it cost?
What Is the Tesla Powerwall?
The Tesla Powerwall is a lithium-ion battery designed for powering a home. It can store the power generated by solar panels and store power taken from the electricity grid.
The advantage of storing power from the grid is that it can act as a backup power source and allow you to charge the battery when power is cheap and use it when it is expensive.
There are currently two Powerwall units available, namely the Powerwall 2 and Powerwall+. These products have replaced the Powerwall 1 which was discontinued in 2016. Tesla also offers the Powerwall 3 which is expected to be available in 2024.
Both the Powerwall 2 and Powerwall+ have the same energy capacity of 13.5 kWh, but the peak and continuous power are different. More succinctly, Powerwall 2 is rated with 5.8 kW continuous on-grid power and 10 kW peak backup power. On the other hand, Powerwall + is rated with a continuous power of up to 9.6 kW and a peak power of up to 22 kW.
The Powerwall 3 battery capacity is similar to Powerwall 2, but it delivers 11.5 kW of continuous power. Another cool thing about the Powerwall 3 battery is that it comes with an in-built inverter and system controller, just like the Powerwall+. Besides that, the Tesla Powerwall 3 will be much easier to install than Powerwall+ and Powerwall 2.
Do You Need Solar Panels to Use a Tesla Powerwall?
The Tesla Powerwall is primarily used by people with solar panels—but they are not a requirement. A Powerwall can be used solely to store power from the electricity grid, but this limits where you can buy one.
Since Tesla Powerwall was introduced in 2015, it was only available for sale if you purchased a solar panel or solar roof from Tesla. However, Tesla has revised those requirements, and you can now order a Powerwall without a solar panel or roof from Tesla—but the availability is limited to select locations.
How Does the Tesla Powerwall Work With Solar?
During the day, the Powerwall takes the energy produced by your solar panels and uses them to power your home appliances. It includes a converter that converts DC power from your panels into the AC power required to power your home.
The energy produced during the day is often more than is needed, and this excess energy is used to charge the Powerwall. This power can then be used at night, providing 24-hour electricity. Depending on where you live, you may also be able to sell your excess electricity back to the power grid.
How Does the Tesla Powerwall Work Without Solar?
If you don't have solar panels, you may still benefit from a Powerwall.
If you live somewhere with electricity that's more expensive during the day, you can charge the Powerwall by night and then use it to power your home throughout the day. Depending on the difference in rates, this can deliver significant savings.
A fully charged Powerwall would also come in handy during an emergency power outage along with other devices to backup your home.
How Much Power Does a Powerwall Provide?
Depending on how much power you use, a single Powerwall may not be enough to completely power your home. However, if you use a lot of electricity, it's worth noting that multiple Powerwalls can be added to a single system.
Capacity
A Powerwall can hold 13.5 kWh of power. This is approximately half of what the average home uses in a day and is more than enough to power a home during the night. If there's a power outage, it can also last longer if you run fewer appliances.
Continuous Power Rating
The continuous power rating of a battery dictates how many appliances it can run simultaneously. For example, a Powerwall can provide 5.8 kW of continuous power. Depending on the size of your house, this should be sufficient to power your lights, electrical sockets, and kitchen appliances. The Powerwall+ can also provide 7.6 kW of continuous power when the sun is out.
How Much Is the Tesla Powerwall?
The Tesla Powerwall starts at $8,400 without taxes and installation costs if purchased directly from Tesla. If you need more than one, the price goes down with quantity. This means you can purchase three Powerwall units for $30,300.
However, it can be more expensive if you add the accessories and installation costs. The average cost of installing a Tesla Powerwall is $6,500—that's if Tesla sends its technician. On top of that, the installation accessories will cost an extra $1,100.
If you do the math, you could spend almost $16,000 to purchase and install a single Powerwall unit. But you could make it more affordable if you claim the 30% residential federal investment tax credit for installing a Tesla Powerwall unit, even if you’re not using solar power. To put it into perspective, if you’re buying two Tesla Powerwall units at $15,700, you could reduce the cost by $5,099 if you qualify for the tax credit.
Depending on the state in which you live, additional rebates may also be available.
Is the Powerwall Worth It?
The Tesla Powerwall isn't cheap, and whether or not it's worth it depends on how you currently power your home. However, if you have solar panels or are about to buy them, the Powerwall is well worth considering. It's competitively priced, well-designed, and from a reputable company.
If you don't have solar panels, or you are buying them in the hope of lower energy bills, it's important to calculate the savings before you buy one. A Powerwall will save some people money, but how much depends on the difference in rates between the day and night.
The reliability of your electrical grid is also worth considering. If you live in an area with regular power outages, you might find the cost of a Powerwall is worth it, even if it doesn't save you money.
However, there are other alternatives you can consider besides Tesla Powerwall. For instance, you could use the Ford F-150 Lightning which is equipped with bidirectional charging capabilities to back up your home. A Ford F-150 Lightning Pro trim with a battery capacity of 98 kWh starts at $49,995 before tax incentive, and it backs up your home for a week if fully charged.
Other alternatives for the Tesla Powerwall include the Panasonic Evervolt, LG Chem Battery, SunPower SunVault, and Sonnen Battery.
Be Prepared to Wait, Even if You Buy Directly
If you'd like to buy a Powerwall, it's important to note that they're not currently the easiest products to buy. If you want to buy directly from Tesla, you need to also order a solar panel. Otherwise, you will need to find an independent retailer and potentially pay more.
Due to the popularity of Powerwall, customers also report significant delays. As of 2021, there was a backlog of 80,000 units and while the current backlog is unknown, you can still expect to wait many months. Tesla also appears to be prioritizing customers who buy directly.