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Solar panels in Olympia, WA

Roofs in Olympia get about 1,240 hours of usable sunlight a year — less than 83% of the cities we've measured. Here's what that means in cost, savings and payback, using real rooftop data rather than a national average.

1,240Sun hours / yr
26Panels typical
$20,748Cost after credit
16.9 yrPayback
Be careful in Olympia. At a 16.9-year payback, solar here is a long-horizon decision, mostly because electricity is relatively cheap (11.3¢/kWh). It can still make sense if rates rise or you have local incentives — but check the numbers hard before signing.

Check your specific roof in Olympia → City averages are a starting point; your own roof's size, pitch and shading change the answer a lot.

What a typical Olympia solar system costs

A 26-panel system (10.4 kW) is about right for an average Olympia home using 10,800 kWh a year. It would produce roughly 10,962 kWh annually and offset 100% of that usage.

Estimated economics by system size in Olympia, at 11.3¢/kWh after the 30% federal tax credit
SystemSizekWh/yr Net costSaves/yrPayback
8 panels3.2 kW 3,373$6,384 $381 16.8 yrs
12 panels4.8 kW 5,059$9,576 $572 16.8 yrs
16 panels6.4 kW 6,746$12,768 $762 16.8 yrs
20 panels8 kW 8,432$15,960 $953 16.8 yrs
26 panels10.4 kW 10,962$20,748 $1,225 16.9 yrs

How we worked this out for Olympia

Every number on this page comes from these seven steps. Nothing is a national average — the sunlight figure is measured from Olympia rooftops.

#StepResult
1What one panel makes here
400W ÷ 1000 × 1,240 sun hrs × 0.85 system losses
422 kWh/yr
2Panels needed to cover typical usage
10,800 kWh ÷ 422 kWh per panel
26 panels
3System size
26 panels × 400W
10.40 kW
4Annual production
10.40 kW × 1,240 hrs × 0.85
10,962 kWh/yr
5Installed cost
10,400 W × $2.85 per watt, then −30% federal credit
$20,748
6Annual saving
3,780 kWh used as generated × 11.3¢  +  7,182 kWh exported × 11.3¢
$1,225/yr
7Payback
$20,748 ÷ $1,225 per year
16.9 years

Step 6 matters more than it looks. Only 34% of what a system this size produces in Olympia is used the moment it is generated; the other 7,182 kWh is exported and credited one-for-one under net metering. Because exports here are credited at or near retail, that split changes the payback very little — 16.7 years against the 16.9 we show. In places where exports pay a fraction of retail the same split moves payback by years, which is why we model it explicitly rather than assuming.

Assumptions: 400W panels, 15% system losses (inverter, wiring, heat, soiling), $2.85/W installed, 10,800 kWh typical annual household use, 11.3¢/kWh electricity. Change any of those and every figure above moves — which is exactly why a single national "solar costs X" number is misleading.

Notice that payback barely improves as systems get bigger, and eventually gets worse. That's because you can only save money on electricity you were going to buy anyway. Once a system covers your usage, extra panels mostly generate exports at a much lower rate.

Why Olympia gets 1,240 sun hours

That figure comes from Google's analysis of real rooftops across Olympia — it already accounts for shading from trees, chimneys and neighbouring buildings, which is why it's lower than the raw "hours of daylight" figures you'll see elsewhere. An unusually open, unshaded roof in Olympia reaches about 1,319 hours, roughly 6% better than typical.

The numbers behind this page

Typical usable sunlight1,240 hrs/yr
Unshaded roof1,319 hrs/yr
Electricity rate (Washington avg)11.3¢/kWh
Installed cost assumed$2.85/W
Panel size assumed400 W
Federal tax credit30%
Typical household usage10,800 kWh/yr
Power used as generated34%
Paid for exported powerfull retail (net metering)
Rooftops sampled here14
Google imagery from2024

When Olympia actually produces

Annual totals hide the thing that catches people out: 39% of Olympia's yearly sunlight arrives in May–July, and just 11% across November–January.

Estimated usable sun hours by month in Olympia (latitude 47.0°)
MonthSun hrsShare of year
Jan 44
Feb 66
Mar 97
Apr 131
May 157
Jun 168
Jul 163
Aug 141
Sep 109
Oct 75
Nov 49
Dec 38

That is a severe seasonal swing — Olympia produces roughly 4.4× as much in Jun as in Dec. A system sized to cover your annual usage will overproduce badly in summer and fall well short in winter, so how your utility credits exported power matters more here than in most places.

The annual total is measured from Google's rooftop imagery. Its split across months is calculated from solar geometry at Olympia's latitude, not separately measured, so treat the monthly figures as the shape of a typical year rather than a forecast.

How Olympia compares to the other 788 cities

MeasureOlympia Rank of 788
Usable sunlight1,240 hrs653rd
Sunlight lost to shade6%300th most
Median roof size238 m²251st largest
Electricity rate11.3¢738th highest
Payback16.9 yrs754th fastest
Grid carbon696 kg/MWh256th dirtiest

What actually stands out about Olympia:

  • Cheap electricity is the headwind. Washington power costs about 11.3¢/kWh. Low rates are good news generally, but they lengthen solar payback — there is simply less bill to displace.

Cities with almost the same sunlight

These are the closest matches to Olympia's 1,240 usable sun hours from other states and provinces. Same sunlight, different electricity prices — which is usually what decides whether solar is worth it.

CitySun hrs RatePayback
Kailua-Kona, HI 1,25342.1¢ 4.5 yrs
Bradford, PA 1,22618.1¢ 10.6 yrs
Gresham, OR 1,25712.4¢ 15.4 yrs
Portland, OR 1,25812.4¢ 15.4 yrs

Nearby cities

See all of Washington → statewide sunlight, rates, incentives and every city we've measured.

Olympia solar questions

How many solar panels do I need in Olympia?

About 26 panels for an average home using 10,800 kWh a year. Olympia roofs get 1,240 usable sun hours, so each 400W panel produces roughly 422 kWh annually. A typical Olympia roof fits about 87 panels, so roof space is unlikely to be your limit.

Is solar worth it in Olympia?

At 11.3¢/kWh and 1,240 sun hours, a typical system pays for itself in about 16.9 years and returns roughly $9,876 over a 25-year panel life. That is slower than average, so compare several quotes before committing. Exported power earns full retail credit here.

How much do solar panels cost in Olympia?

A 10.4 kW system costs about $29,640 before incentives and $20,748 after the 30% federal tax credit. That works out near $2.85 per watt installed. Roof pitch, shading, electrical panel upgrades and equipment choice move the price most, which is why quotes for the same house can differ by thousands.

Worth reading before you buy

Estimates only, generated 2026-08-22 from Google Solar API rooftop samples and average Washington electricity rates. Not a quote and not financial advice. Your roof, usage, utility plan and local incentives will change these numbers — get real quotes before buying.