How Many Solar Panels Do You Really Need for Your Home in Arizona?

If you're like many Arizona homeowners exploring solar, one of the first questions you’ll ask is: "How many solar panels will I need?" It's a great question—and the answer depends on several key factors unique to your home, your habits, and your long-term goals.

At Advanced Electric & Solar, we believe in providing clear, transparent guidance. So let’s walk through everything that affects system size—from your electricity usage to panel type and even your future plans (like getting an EV or adding a hot tub!).

Step 1: Understand Your Monthly Electricity Usage

Your electricity bill is the best place to start. Look for your kilowatt-hour (kWh) usage, ideally across 12 months to account for seasonal swings.

• Average Arizona home usage: 1,000–1,300 kWh/month
• Higher energy homes (e.g., pool, EV, large families): 1,500+ kWh/month
• Lower energy homes (condos, retirees): 700–900 kWh/month

Tip: APS or SRP customers can download a 12-month usage report from their utility portal.

Step 2: Consider Your Energy Goals

Some homeowners want to offset all of their usage. Others want to reduce their bill partially and leave room for future upgrades. Your goal directly impacts how many panels you'll need:

Step 3: Factor in Roof Space and Orientation

Not all roof space is usable. Shading, pitch, vents, chimneys, and direction all play a role.

• Best direction: South-facing (optimal sun exposure)
• Good alternatives: West or southwest
• Challenging setups: East-facing, shaded, or multiple roof levels

Advanced Electric & Solar uses drone roof scans and solar modeling software to determine the most efficient layout and maximize usable space.

Step 4: Choose the Right Solar Panel Type

Not all solar panels are created equal. Panel efficiency has a big impact on how many you’ll need.

Fewer high-efficiency panels may be needed to produce the same output, which is ideal for smaller roofs or those with partial shading.

Step 5: Consider Your Climate & Location

Arizona’s sunny climate is a major advantage, but local weather, elevation, and dust can still affect performance. Panels in Phoenix or Tucson typically generate:

• 5.5 to 6.5 kWh per kW installed, per day
• That’s 1,650–1,950 kWh per year for each kilowatt installed

So, a 7 kW system could generate roughly 12,000–14,000 kWh per year, depending on location and panel tilt.

Example: Calculating Panel Needs

Let’s say your annual usage is 13,000 kWh, and you want full coverage:

• You choose 400W high-efficiency panels
• Each panel generates ~1,700 kWh/year in Arizona sun
• You’d need 13,000 ÷ 1,700 = ~8 panels

BUT… to account for system losses, real-world conditions, and future usage growth, we recommend bumping that number by 20–25%. So:

Final estimate: 10–11 high-efficiency panels

For standard 300W panels, you’d need 15–18 panels for the same coverage.

 Planning Ahead: EVs, Pools, and More

Thinking about installing an EV charger or pool pump in the next few years? Future-proof your system now:

• Add 2–4 extra panels for an electric vehicle
• Add 1–2 extra panels for pool or hot tub usage
• Consider battery storage if you want backup power or time-of-use savings

Let Us Do the Math for You

The best way to know how many solar panels your home needs? Let us model your home for free.

At Advanced Electric & Solar, we:

• Analyze your utility usage
• Assess your roof and sun exposure with aerial tools
• Design a custom layout for maximum output
• Provide transparent, no-pressure pricing

Ready to find out how many panels you need?
Schedule your free solar consultation or give us a call today.