How Many Tesla Powerwalls Do I Need for My Home?
March 9, 2023
Most solar panel owners eventually, if not immediately, consider solar batteries to complement their solar system. If you’ve made your way to this article, you’re likely one of them.
Are you in the market for a solar battery and wondering how many Tesla Powerwalls you need for your home? In short — it depends.
Several factors play into how many Powerwalls you need. You’ll want to consider your household’s average energy consumption and the amount of stored power that you’ll want available.
Let’s explore the factors that go into the decision.
Consider Your Household Size
As of 2022, the average U.S. household size was about 2,500 square feet. Meanwhile, a household’s average electricity consumption was 886 kWh per month in 2021. After a bit of math, that equals about 29 kWh daily.
We’ll assume those numbers stay roughly the same into 2023.
Think about doubling that — a 5,000-square-foot house would consume a bit over 1,700 kWh monthly. Then, there are additional factors that determine whether this number is more or less:
- How many people live in the household
- The location of the home and how much A/C demand is needed
- The home’s appliance efficiency
- The residents’ general lifestyle habits
Once you’re able to understand your household’s energy consumption, you can determine how much backup power you’ll need.
[Related: Tips To Save on Energy Costs]
Home Backup Power: How Much Do You Need?
Let’s say there’s a blackout, such as the one that Winter Storm Uri caused in Texas in 2021. The grid has stopped working, and you need a power source to keep the lights on and your appliances running until the grid is back up.
Based on the average household consumption, one Tesla Powerwall would be able to keep the lights on for a family of four through a power outage for four to six hours during an outage, at night or when electricity is at peak use. A Tesla Powerwall provides 13.5 kWh of energy per day when fully charged. This will keep the lights, fridge, TV and other basic household appliances like microwaves on. However, a Powerwall will stop supplying power when it’s charging state hits 10%, so to be safe, Powerwall owners should account for 12kWh of energy during an outage.
But remember: Powerwalls aren’t guaranteed to get you fully off-grid.
Whether you want partial or whole-home backup relies on the number of Powerwalls you have, how much energy you use daily and how long you use a Powerwall without recharging it.
Note. If you’re not sourcing any power from the grid, you’ll likely need more than one Powerwall to maintain power during an outage.
What Does a Whole-Home Backup System Need?
Now, let’s go over some of the additional energy needs that might put you above the average daily power consumption. This will determine whether a whole-home backup system is realistic for you.
Let’s say your family wants to be able to power an air conditioner, your basic energy needs (think lighting and refrigerator), plus major appliances (like a washer, dryer and Tesla charger for an electric vehicle).
You’ll probably need at least two Powerwalls. Having two will be able to back up both essential and nonessential energy loads.
However, a whole-home backup isn’t guaranteed to work. The amount of energy you use and how long your Powerwalls go uncharged factor into how long you can stay powered up.
With whole home backup, all your 120 and 240 voltage appliances are connected to the Powerwall through one circuit. The user must manually shut off the 240 voltage appliances in the event of an outage to conserve power.
Contact Freedom Solar for Reliable Solar Batteries
Once you’ve considered your house size, energy consumption and home backup power preferences, contact one of our energy consultants at Freedom Solar. They’ll be able to put together a customized plan based on your specific needs.
Looking to maintain, repair or upgrade your solar system? Our solar repair and maintenance service department can help you obtain maximum energy production and efficiency.
To get started today, call (800) 504-2337 or complete our online inquiry form. One of our energy consultants will be in touch!