How Arizona's Climate Makes It One of the Best Solar States

Arizona's solar advantage starts with the sun

Phoenix gets around 299 sunny days a year. The National Renewable Energy Laboratory puts Phoenix's annual peak sun hours at roughly 6.5, which is among the highest of any major metro in the country. For context, Seattle averages about 3.5. Portland sits around 4. Even Los Angeles, famous for its sunshine, lands closer to 5.7.

What does that gap mean in practice? Every extra peak sun hour translates directly to more kilowatt-hours your panels produce, which means more of your APS or SRP bill that gets wiped out. A system that produces 15 kWh per day in a cloudier state might produce 20 or more right here in the Phoenix Valley.

If you're curious how much solar your specific home could generate, the solar calculator at PhoenixValleySolar.com gives you a custom estimate based on your roof size, orientation, and utility provider.

How Arizona heat actually affects panel performance

Here's where a lot of homeowners get confused, and it's one of the most common solar myths we hear from Arizona homeowners: that intense summer heat hurts solar panel output to the point where going solar isn't worth it.

The truth is more nuanced. Solar panels do lose a small amount of efficiency as temperatures climb above 77 degrees Fahrenheit, typically around 0.3% to 0.5% per degree Celsius above that threshold. During peak Phoenix summers, when rooftop temperatures can reach 150 degrees, output can drop by roughly 10% to 15% from rated lab conditions.

But Arizona's solar irradiance, meaning the raw volume of sunlight hitting your panels, more than compensates for that efficiency loss. A panel producing 90% of its rated output for 6.5 hours still outperforms a panel running at 100% efficiency for 4 hours. The math works in Arizona's favor almost every time.

Modern panels are also built with low temperature coefficients, meaning they handle heat better than older models did. If you want to know what panels Phoenix Valley Solar works with and why, our team explains it on the about page.

The numbers behind Arizona's solar savings

APS residential customers in Maricopa County pay some of the steepest summer rates in the Southwest. Under the APS Saver Choice Plus plan, on-peak rates during summer months run above 28 cents per kWh between 3 PM and 8 PM. A typical Phoenix home using 1,800 kWh per month in summer will see electric bills regularly exceeding $250.

A properly sized solar system in Phoenix can offset 80% to 100% of that consumption, depending on roof space and shading. Over 25 years, that adds up considerably. And unlike utility rates, which APS has raised multiple times in the last decade, your solar production cost is locked in from day one.

That fixed-cost advantage is a big reason understanding how solar works on APS versus SRP matters before you commit. Each utility has a different billing structure, and the right solar setup for your home depends on which one you're on.

City-specific solar performance across the Phoenix Valley

Not all Phoenix Valley cities perform identically, but the differences are smaller than most people think. What matters far more than your ZIP code is roof orientation, shading, and system size.

Phoenix proper sits at roughly 33.4 degrees latitude and receives an annual solar resource of about 6.5 peak sun hours when panels are tilted optimally. Homes with south-facing or west-facing roofs see the best return on investment across almost any financing structure.

Scottsdale and Paradise Valley homeowners benefit from the same desert climate, and those cities also have some of the highest median home values in Arizona. Research from Lawrence Berkeley National Laboratory found solar adds roughly 4% to a home's resale price on average. In Scottsdale, that translates into real dollars.

Mesa and Gilbert sit in the East Valley where summer temperatures run especially high, but that works in solar's favor for total annual production. Homeowners in these cities who sized their systems correctly report offsetting 90% or more of their electricity use even in July and August.

Chandler has become one of the fastest-growing cities in Arizona, and new construction there increasingly includes solar-ready roofs. Existing homeowners who haven't installed yet are in a strong position because south-facing roof space is the norm in most Chandler neighborhoods.

Tempe and Ahwatukee see strong solar performance year-round. The proximity to ASU gives these communities a higher concentration of homeowners who have already done the research and know the numbers work in their favor.

Why the prepaid solar lease changes the calculation

The biggest barrier most Phoenix Valley homeowners face isn't sunlight. It's upfront cost.

A residential solar system typically runs between $18,000 and $28,000 before any incentives. That's a significant amount for most families to deploy out of pocket, and solar loans come with interest rates that can eat into a large portion of long-term savings.

The prepaid solar lease solves this directly. Instead of buying the system or financing it with a loan, you prepay for 25 years of solar energy production at a 30% discount off the installer's standard rate. There's no monthly payment, no interest, and no maintenance cost. The installer handles all of that.

For Arizona homeowners, this structure matches the climate especially well. Because Phoenix gets so much sunlight, you're pre-purchasing a large, predictable block of energy production. The more sun the state gets, the more value that prepaid block represents over time.

To see how this applies to your specific home, use the solar calculator or reach out to our team for a no-pressure estimate.

What Arizona's solar advantage means over the long term

One thing that doesn't get discussed enough is what Arizona's solar advantage means over a 20 to 25-year horizon.

Utility rates in Arizona have not stayed flat. They've gone up. APS has sought and received rate increases from the Arizona Corporation Commission repeatedly over the last decade. SRP, which sets its own rates without ACC oversight, has also raised prices multiple times in recent years.

Solar locks in your production cost. If you prepay a lease today at today's rates, the value of that agreement grows every time APS or SRP raises its rates. By year 15 or 20, the gap between what you'd be paying on the grid versus what your solar costs is substantial. Arizona homeowners who went solar in 2015 are paying decade-old production rates while their neighbors absorb each new rate increase.

That's not a small advantage in a state with as much solar potential as Arizona. It's a structural one. The longer you wait, the more rate increases you absorb before locking anything in.

Frequently asked questions

Does Arizona's heat make solar panels less efficient?

Panels do run slightly less efficiently at very high temperatures, typically losing 10% to 15% of rated output during peak Phoenix summer heat. But Arizona's 6.5 average peak sun hours more than compensate. Total annual energy production in Phoenix is consistently higher than in cooler but cloudier states.

How many peak sun hours does Phoenix get compared to other states?

Phoenix averages around 6.5 peak sun hours per day annually. Seattle averages about 3.5 and Los Angeles about 5.7. This is one reason Arizona consistently ranks among the top states in the country by residential solar capacity per household.

Will solar panels work on my roof during Arizona's monsoon season?

Yes. Arizona's monsoon season runs roughly July through September and brings short, intense storms, but the rest of those months are still sunny. Annual production projections for Phoenix-area systems already account for monsoon weather patterns, so the numbers you see upfront are realistic.

Is a prepaid solar lease a good fit for Arizona homeowners?

For most Phoenix Valley homeowners planning to stay in their home for at least 7 to 10 years, the prepaid lease is one of the most cost-effective ways to go solar. You save 30% off standard installation rates, avoid loan interest, and benefit from Arizona's high solar production year-round. Visit our solar calculator to see what your specific savings could look like.

Does Arizona have any state-level solar incentives?

Yes. Arizona has a state income tax credit for residential solar installations, and the state also exempts solar equipment from sales tax and installed solar systems from property tax increases. These benefits pair well with the 30% savings from the prepaid lease structure, making Arizona's solar economics hard to match anywhere else in the country.