How Long Does A Tesla Powerwall Last?

The Tesla Powerwall has become a staple in many households since the rise of Tesla, but what is it, and how long can a Powerwall provide power for?

Speaking generally, a Tesla Powerwall will run for an average of 12 to 15 hours, but this will vary from household to household depending on various factors. 

In this article, we will be taking a closer look at the Tesla Powerwall and these factors in order to see exactly how long it can last within a regular home, as well as to get some general information on the product.

Let’s get started.

How Long Does a Tesla Powerwall Last?

What Is A Tesla Powerwall?

Introduced with limited production in 2015, the Tesla Powerwall is a battery created by Tesla Energy that was designed specifically for use in households as a home energy storage battery.

The Powerwall is a stationary lithium-ion battery that is rechargeable.

Mass production of the Tesla Powerwall began in early 2017 and by May 2021, around 200,000 Powerwalls have been installed within homes.

How Does The Tesla Powerwall Work?

The Powerwall functions by storing electricity in order to save it as a backup power source.

The stored energy is taken directly from either the grid or from solar energy and is then available whenever you may choose to use it.

An example of when one might make use of a Powerwall would be during a power outage or a blackout.

How Much Power Can The Tesla Powerwall Hold?

The general storage capacity of the Tesla Powerwall is around 13.5 kWh, which allows for a continuous power output of up to around 9.6 kW.

There are also three different operating modes within the Powerwall: Time-Based Control Mode, Solar Self-Consumption Mode, and Backup Only Mode.

How Long Does A Tesla Powerwall Last?

The average consumption of energy for one home in a day is around 28 kWh and so typically, with this average rate in mind, a Powerwall can run for up to 12 to 15 hours.

However, this will of course vary depending on factors such as usage, home size, and what kind of appliances are being used most often with the Powerwall.

The Powerwall will last longer when it is only running one appliance at a time.

However, if it is being used to power multiple appliances, such as light bulbs, fridges, televisions, phone chargers, or Wi-Fi routers, then the energy held within the Powerwall is inevitably going to be depleted faster.

A small household can use as little as 10 kWh a day, whereas a larger home can use around 40 kWh or even more.

This question all comes down to these various factors, so to get a more accurate estimate as to how long a Powerwall will last, you will need to perform a calculation based on two specific pieces of information.

This information is as follows:

  • How much power can the Powerwall- or Powerwalls- in your home create?
  • How much power does your home need?

Let’s look at these two questions a little more closely.

How Much Power Does The Powerwall Provide?

How Much Power Does The Powerwall Provide?

For a single Tesla Powerwall, there are two ratings that you need to consider: the continuous power rating and the instantaneous power rating

Continuous power refers to the power that the wall can provide over a long period, whereas instantaneous power relates to the power needed to start up your appliances.

One Tesla Powerwall offers 5kW of continuous power and 7kW of instantaneous power.

How Much Power Does Your Home Need?

To know exactly how much power you are going to need, you will have to make note of which appliances you know you will definitely need to back up in the event of a power loss.

Once you have narrowed these appliances down, the power usage of each of these appliances will need to be calculated.

You can try and do this yourself, or you can work alongside your installer to get the most accurate results possible.

Once the wattage of all the individual, necessary appliances has been deciphered, you should be able to find an estimate of the collective power that will be needed from the Powerwall in an outage situation.

By comparing the answers to these two questions, you should be able to get a more accurate answer to the question of how long the Tesla Powerwall last.

Once you have all the information on the most important appliances in your home, and you know just how much power your Powerwall- or Powerwalls- offers, you are ready to calculate the specifics.

Calculating Power Requirements

Luckily, it is not too difficult to get a more accurate estimate of the amount of power that you will need from a Powerwall.

Batteries such as the Powerwall run via amps (A) or kilowatts (kW). Kilowatts are a measurement of power, whereas amps are a measurement of current.

In order to calculate amps into kilowatts, you just need to follow this simple formula:

  • (Amps x Voltage) /1,000 = Kilowatts

When calculating just the watts, all you need to do is remove the dividing by 1,000 part of the equation, so the formula will look like this instead:

  • Amps x Voltage = Watts

With this formula, you should be able to make a more accurate estimate of the amount of power that each appliance will need.

Compare this total with the power output from your Tesla Powerwall and there you have it!

Final Thoughts 

As you can see, the amount of time that a Tesla Powerwall will last all depends on the energy consumption within your home as well as how often you need to use it. 

To get the most accurate results, so that you know exactly how long your Powerwall will last when you need it most, follow our guide above, and you should be able to get a much clearer picture of your Powerwall’s lasting power as well as a better idea of the energy usage in your home.

Jonathan Rice