How to Choose the Right Battery Size for Your Solar System in Phoenix

Are you considering solar energy for your home in Phoenix? Now is the perfect time to harness the power of the sun and take advantage of significant savings through federal and state tax credits. Our team at Phoenix Valley Solar can help you navigate these incentives and maximize your savings. You can also use our Arizona Solar Calculator to get an estimate of your potential benefits.

Adding battery storage to your solar setup can significantly increase your energy savings and improve your home’s resilience during outages. But one of the most important questions to answer before installing storage is: how much battery capacity do you really need?

In Phoenix, Scottsdale, and Mesa, homes vary widely in size, energy use, and backup priorities. Whether you want full home backup or just enough to cover essentials during peak hours, choosing the right battery size is key to getting the most from your system.

What Battery Size Means for Solar Storage

Battery size is measured in kilowatt-hours (kWh), which tells you how much electricity the battery can store and deliver. For example, a 13.5 kWh Tesla Powerwall can run a refrigerator, lights, Wi-Fi, and a few outlets for several hours.

If your home consumes 30 to 50 kWh per day, you likely won’t run your entire home on one battery. Instead, most homeowners prioritize backup for essentials or focus on shifting usage to avoid peak utility rates.

Installing the right size battery ensures you get the benefits you want—without overpaying for capacity you don’t need.

Factors to Consider When Sizing a Solar Battery

There’s no one-size-fits-all answer, but here are some things to consider:

• Your daily energy use: Look at your electric bill to see how many kilowatt-hours your home uses per day, and how that use is distributed between day and night.

• Your goals: Are you looking for full-home backup, protection for essentials during outages, or to avoid peak-time utility rates?

• Your current solar production: If your panels already generate excess energy, you may be able to store more during the day.

• Your rate plan: APS and SRP customers on time-of-use plans benefit from batteries that can shift evening usage to lower-cost daytime power.

• Available space and budget: Batteries like the Tesla Powerwall are compact and can be installed indoors or out—but each unit adds cost.

A solar plus battery system in Phoenix should be tailored to your home’s needs, not just installed based on generic sizing.

When One Battery Is Enough

Many homeowners in Phoenix choose to start with a single Tesla Powerwall installation. With 13.5 kWh of storage, it can:

• Power essential appliances during outages

• Offset peak-hour grid usage under APS or SRP plans

• Store solar power for use after sunset

• Provide energy savings without needing full-home backup

If your energy needs grow in the future, you can always add additional units.

When to Consider Multiple Batteries

You might benefit from two or more batteries if you:

• Use a lot of energy after sunset

• Have a large home or multiple air conditioning units

• Want to power your whole home during extended outages

• Charge an electric vehicle overnight

• Have life-supporting medical equipment in the home

Our team designs systems with the flexibility to grow. Whether you live in Mesa, Phoenix, or Scottsdale, we’ll help you plan for your current lifestyle and future energy goals.

Why Work with Phoenix Valley Solar

We provide complete services for:

• Solar panel installation in Scottsdale

• Solar panels in Mesa AZ

• Solar battery storage in Phoenix

• Home solar battery backup systems

• Tesla Powerwall installation and integration

• Full custom design of solar plus battery systems in Phoenix

As a local expert, we understand Arizona’s climate, utility rates, and power challenges—and we build systems that perform in the desert heat.

Get the Right Battery for Your Home—No More, No Less

Contact Phoenix Valley Solar today for a custom battery sizing consultation. We’ll analyze your energy use, discuss your priorities, and design a storage solution that meets your needs and your budget.

Are you considering solar energy for your home in Phoenix? Now is the perfect time to harness the power of the sun and take advantage of significant savings through federal and state tax credits. Our team at Phoenix Valley Solar can help you navigate these incentives and maximize your savings. You can also use our Arizona Solar Calculator to get an estimate of your potential benefits.