Battery Backup for Home Power Outages

As a new or old homeowner, you may be considering your options for power - do you use solar? Do you use the grid? Should you have a battery, or just a generator? The answers to these questions are subjective, as in, it’s dependent on your location and needs, or wants. 

Last updated
June 30, 2024
Author: Matt from Currents
Learn about energy for your home or business.

A battery backup is a solution for residential homes when a power outage or extreme weather event occurs. If you've lost power to the grid or your solar panels are not generating photovoltaic energy, a home battery can solve your problem in a pinch by automatically turning on and providing energy to your home for 8-12 hours.

A home battery also provides a way to save money on your bills through time-of-use pricing plans and reliability, guaranteeing that you have power when you need it most while also being environmentally conscious.

When choosing a home battery backup, there are a number of factors to consider. Let’s take a closer look at battery backup systems here at Currents.

Battery Backup for Home Power Outage

Your whole home battery operates in congruence with solar by doing the following:

1. The solar panels generate direct current, or DC, electricity from the sun.
2. The DC solar energy flows through an inverter, which converts it to alternating current, or AC, electricity.
3. Your home and it’s appliances then run on the AC electricity.
4. Any extra energy not used charges your battery and is stored inside it.
5. When your power goes out or you tell it too, the energy within your battery will then power your home.

Note: it is not necessary to have solar to utilize a battery for your home. You can still install and operate a home battery without solar by instead relying on the energy from the grid to be stored within your battery.

This would then result in your home’s backup reliability being dependent on how much is already stored within the battery from the grid when an outage occurs as it will not be able to re-charge without being active on the grid if solar is not attached. 

What to Look for in a Battery Backup for Home Power Outage?

There are a number of things to look out for when searching for a battery backup solution for your residential, things like:

Capacity

The capacity of your battery determines the amount of power the battery can store. Whole home batteries on the market today have a variety of capacities.

The average capacity is around 13 kWh and is useful for powering appliances like refrigerators and air conditioning systems. For example, the current Tesla Powerwall system has a capacity of 13.5 kWh

Tesla Powerwall capacity chart

Power

The power of your battery is what determines it’s ability to meet the demand of your residential home. Each battery company lists the peak power output, the continuous power output, and the compatibility with appliances. 

Check out this home battery comparison chart (est. spring 2024)

Cost

The cost of your battery fluctuates depending on the capacity, power, brand, warranty, features, quality, and other factors such as installation and location and incentive programs.

Like most things, there are low-to-high budget systems to choose from on the market.

According to our sources on current prices as of Spring 2024, it is around $1,339/kWh of stored energy or $13,000 for a 10 kWh battery and, depending on your location, there are some incentives for using a battery with or without solar. 

As with all technologies, costs are plummeting and the supply of residential batteries for homes is exploding. We expect these prices to continue to drop.

 

Brand

The brand of your battery matters as a reputable brand will provide the quality and consistency that you need to ensure your battery is up to par before, during, and after installation.

Based on our findings, high trust brands like Tesla, FranklinWH, Enphase and LG are good brands to install.

FranklinWH home battery
FranklinWH is an American brand in the home battery market

Warranty 

The warranty of your battery depends on the battery itself. Most batteries have a 10-year warranty while others, like the FranklinWH Battery, have a 12-year warranty.

Also, some batteries are covered up to a certain usage point - you can check out what that is and determine if your battery will last as long as you expect it too. 

With most whole home battery systems, you can purchase additional batteries for an increased capacity and power output. That’s not to say you won’t lose some charge over time, as the battery will do so regardless of the amount of batteries you have at home. 

FAQs

How to choose a home battery

Carefully look at your energy usage or assumed energy usage and compare various batteries on the market to see if any of them fit your home’s power demand either full-time or just during a blackout.

Also, check to see what the weather conditions or grid performance is like in your area. Will you just need the battery for a few hours here and there, or are there days, or even weeks, of expected downtime?

What’s the difference between a home battery and a generator?

The cost of a home battery is exponential compared to a generator, but the cost to refuel a generator is more if you have your battery hooked up to solar.

Plus, you can usually plug your generator in yourself while whole home batteries typically require the manufacturer or a specialist to install. The good thing about home batteries is the sound is quiet - a generator is very loud, and powered by fossil fuels and have emissions, unlike a battery backup system.  


Sources

Home Battery Backup Systems Explained | All You Need to Know - Anker US

The Complete Buyer's Guide to Home Backup Batteries in 2023 | EnergySage

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