How Many Solar Batteries Are Needed to Power a House?

Probably the most asked question people have when it comes to solar energy systems is: “How many solar batteries do I need to run my house.” Truthfully, this depends on a number of factors: energy usage, the size of the solar panel system, the capacity of the batteries, and how long you want to store energy.

In this article, we take a closer look at how to determine the number of batteries that will be required, how solar batteries work, and further benefits derived from using them.

We’ll also be discussing the FranklinWH: the leading energy storage solution to upgrade your solar power system.

Solar batteries are such a system that saves the extra energy produced by your solar panels. Because your solar panels would only produce energy when the sun is out, it gives a leeway for storing that energy for cloudy days, nighttime, or other power outages. Without batteries, one would have to depend on the grid for this power when the solar panels cannot create enough electricity.

How Solar Batteries Work?

Basically, solar batteries store energy in chemical forms. During the day, when the solar panels are producing more electricity than what the house is using, the excess energy goes to the battery. The battery will then send this energy for later usage. At night, or during periods of low sunlight, the stored energy is drawn from the battery into powering the home.

Factors That Determine How Many Solar Batteries You Need

Here is a step-by-step process to enable you to estimate how many solar batteries you need to run your house:

1. Daily Energy Usage

The first and foremost step in calculating how many solar batteries one is likely to require for the establishment of a home is an understanding of the daily energy usage of a particular household. On average, a single day in most homes in America uses around 30 kWh of electricity. This amount, however, greatly varies depending on:

• The number of individuals dwelling within the house
• The size of the house
• Energy-efficient appliances
• The application of electric heating or cooling systems

To estimate these daily energy needs, consult your electric utility bill, which is generally based on the quantity of kWh you consume each month. Divide it by 30 to provide the average daily usage.

1. Battery Capacity

Every solar battery tends to have a specific storage capacity, usually rated in kWh. For instance, the Tesla Powerwall has a storage capacity of 13.5 kWh, whereas Franklin aPower 2, boasts a market-leading 15 kWh capacity. With that logic, this means you are going to divide your requirement by the capacity of a battery that you are using or intend to use.

Example:

For a house that consumes 30 kWh a day, using a Tesla Powerwall rated for 13.5 kWh, one would divide 30 by 13.5 to find that two Tesla Powerwalls store enough energy for one day.

Remember that most homeowners do not need to store their whole day’s usage in batteries. If you can supplement your battery storage with grid power, you might not need as many batteries.

1. Autonomy and Backup Time

Autonomy refers to the number of days you may want to depend on your solar batteries without recharge. If you want your system to be able to give backup power for several days during a power outage or extended periods of cloudy weather, you will need more battery storage.

That means if you wanted your home to sustain itself for two days without the sun, you’d have to double up your battery storage. With that in mind, a house using 30 kWh of electricity per day would need 60 kWh of battery storage.

1. Depth of Discharge (DoD)

DoD means the depth of discharge, the amount of energy available to the battery before it’s noted that recharging is necessary. Thus, when a battery has a 100% DoD, you can use all of the energy stored in it. Yet for some lower DoDs, 80% capacity of the battery can be utilized. Be sure to consider the DoD of the backup battery for home you will buy because this would show how much energy is available to your households.

1. Solar Panel System Size

Size does indeed matter when it comes to your solar panel system, and this will make a great difference in how many batteries you’ll need. It goes without saying that a larger solar array will generate the most energy and thus let you store more excess energy in extra batteries. Another thing that you will need to factor in is knowing how much energy, on average, your solar panels produce each day.

For example, if your solar system is producing 40 kWh/day, you may want to store a portion of that energy for the nights or inclement weather during periods when you normally consume the most energy. So, you will have to install a home battery backup system accordingly.

FranklinWH: Enhancing Solar Energy Efficiency

FranklinWH offers a solution to help homeowners further optimize their solar energy systems. The product they have at the moment is called FranklinWH Energy Management System : a smart energy storage solution designed to work in harmony with solar panel systems.

Key Features of FranklinWH:

• An Open Energy Ecosystem：FranklinWH solution is an open and robust home energy ecosystem that integrates solar, battery, grid, generator and EV power sources, providing whole-home power backup during outages, peak periods, or even when you want to be off-grid 24/7.

• Market-leading battery storage: 10 kW output power & 15 kWh capacity per aPower 2 battery; 15-year warranty & 60 MWh throughput; LFP battery for enhanced safety; one aPower 2 battery provides whole-home backup.
• Efficiency: FranklinWH is highly efficient in its functioning and ensures that a significant amount of the solar energy produced is stored and used effectively.
• Long Service Life: The sturdy construction of Franklin WH batteries is to take the chances of years of service, which directly translates to less expense and reliability over a long period.
• Smart Energy Management: This carries the use of a user-friendly app through which the home can monitor electrical usage, home energy management system, and optimization according to real-time data in use.
• Scalability: FranklinWH system is  designed to scale up to 225 kWh  (15 units) per aGate, giving superior flexibility to meet your diverse needs. 
• Agnostic to all inverters: FranklinWH system is compatible with all solar inverters, making installations a breeze for both retrofits and new installations. 

FranklinWH provides a reliable and efficient yet intelligent solution for the maximization of your solar investment.

Conclusion

The number of solar batteries mainly depends on daily energy consumption, battery capacity, amount of backup required, and the size of the solar panel system. Considering all these aspects will help you understand how much energy storage will suffice for you.

FranklinWH provides an excellent solution for those homeowners who want more than just installing solar energy, seeking efficient and scalable whole home battery backup options to meet their energy needs reliably. FranklinWH can help maximize your solar power and lessen reliance on the grid, whether you’re installing solar for the first time or upgrading your current system.