How to Size a Solar Panel System for Your Home in Arizona

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.

One of the most common questions homeowners ask when exploring solar energy is: How many solar panels do I actually need?

There’s no one-size-fits-all answer. The ideal solar system size depends on your electricity usage, roof space, and long-term energy goals — especially in a state like Arizona, where sunlight is abundant and cooling costs are high.

Here’s how to accurately size your solar panel system to maximize your savings and performance under current Arizona solar incentives and policies.

1. Start with Your Annual Electricity Usage

The first step in sizing your system is understanding how much electricity your home uses in a year. Your utility bills will show this in kilowatt-hours (kWh).

In Phoenix and surrounding areas, the average home uses 11,000 to 14,000 kWh per year — but large homes, pool owners, or homes with EVs may use more.

Pro tip: Use your full 12-month billing history to account for seasonal variation in air conditioning use.

2. Consider Arizona’s Solar Production Potential

Arizona has one of the highest solar production rates in the U.S. thanks to more than 300 sunny days a year.

On average, solar systems in Arizona produce 1,600–1,800 kWh per year per installed kilowatt (kW) of system size.

That means:

• A 5 kW system will produce roughly 8,000–9,000 kWh annually

• A 7.5 kW system will produce 12,000–13,500 kWh

• A 10 kW system will produce 16,000–18,000 kWh

Your installer should use site-specific data (roof tilt, shading, azimuth) to give you a more exact estimate.

3. Factor in Roof Size and Panel Wattage

Modern solar panels range from 370W to 450W per panel, meaning you’ll need fewer panels to hit your target energy output than you would have five years ago.

A typical residential panel system in Arizona includes 16 to 28 panels, depending on:

• Panel efficiency

• Energy usage

• Roof orientation and usable space

At Phoenix Valley Solar, we design systems that fit your roof while maximizing production.

4. Decide If You Want to Offset 100% of Your Usage

Many Arizona homeowners aim to offset 100% of their energy usage with solar, especially as utility rates continue to rise.

However, you may choose to offset a smaller percentage if:

• You have limited roof space

• You’re planning to reduce your energy use

• You plan to install solar battery storage and shift energy use

Regardless of your goal, Arizona’s net metering policy (technically net billing) allows you to send excess energy back to the grid and earn credits, increasing your flexibility.

5. Account for Future Usage Increases

If you're planning any of the following, you may want to size your system slightly larger:

• Purchasing an electric vehicle

• Installing a pool or spa

• Expanding your home or household size

• Working from home more often

These additions can increase your kWh usage and affect your solar panel ROI in Arizona, so sizing your system with growth in mind is a smart move.

6. Use Incentives to Your Advantage

No matter what size system you choose, be sure to take full advantage of available solar incentives:

• 30% Federal Tax Credit

• $1,000 Arizona Solar Tax Credit

• Sales and property tax exemptions

• Credits for excess production under the Arizona net metering policy

These programs lower your upfront cost and shorten your payback period — making your solar investment more profitable over time.

7. Work with an Experienced Arizona Installer

The best way to get the right system size for your home is to work with a reputable, experienced installer that:

• Analyzes your usage and roof layout

• Considers current and future energy needs

• Understands local policies, incentives, and utility rate structures

At Phoenix Valley Solar, we design every system custom to your home — not a cookie-cutter setup based on averages.

Final Thoughts: Right-Sizing Maximizes Savings

The right solar system size will:

• Reduce your electricity bill

• Deliver a strong return on investment

• Work efficiently with Arizona’s incentive and billing policies

• Add long-term value to your home

Getting it right from the start ensures you save the most over your system’s 25+ year lifespan.

Ready for a Custom Solar Estimate?

Phoenix Valley Solar specializes in precision system design tailored to Arizona homes. We’ll help you determine how many panels you need, how much you’ll save, and how to get the most out of Arizona solar incentives.

Contact us today for a free consultation and custom solar proposal.

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.