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.
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.
| System | Size | kWh/yr | Net cost | Saves/yr | Payback |
|---|---|---|---|---|---|
| 8 panels | 3.2 kW | 3,373 | $6,384 | $381 | 16.8 yrs |
| 12 panels | 4.8 kW | 5,059 | $9,576 | $572 | 16.8 yrs |
| 16 panels | 6.4 kW | 6,746 | $12,768 | $762 | 16.8 yrs |
| 20 panels | 8 kW | 8,432 | $15,960 | $953 | 16.8 yrs |
| 26 panels | 10.4 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.
| # | Step | Result |
|---|---|---|
| 1 | What one panel makes here 400W ÷ 1000 × 1,240 sun hrs × 0.85 system losses |
422 kWh/yr |
| 2 | Panels needed to cover typical usage 10,800 kWh ÷ 422 kWh per panel |
26 panels |
| 3 | System size 26 panels × 400W |
10.40 kW |
| 4 | Annual production 10.40 kW × 1,240 hrs × 0.85 |
10,962 kWh/yr |
| 5 | Installed cost 10,400 W × $2.85 per watt, then −30% federal credit |
$20,748 |
| 6 | Annual saving 3,780 kWh used as generated × 11.3¢ + 7,182 kWh exported × 11.3¢ |
$1,225/yr |
| 7 | Payback $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 sunlight | 1,240 hrs/yr |
|---|---|
| Unshaded roof | 1,319 hrs/yr |
| Electricity rate (Washington avg) | 11.3¢/kWh |
| Installed cost assumed | $2.85/W |
| Panel size assumed | 400 W |
| Federal tax credit | 30% |
| Typical household usage | 10,800 kWh/yr |
| Power used as generated | 34% |
| Paid for exported power | full retail (net metering) |
| Rooftops sampled here | 14 |
| Google imagery from | 2024 |
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.
| Month | Sun hrs | Share 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
| Measure | Olympia | Rank of 788 |
|---|---|---|
| Usable sunlight | 1,240 hrs | 653rd |
| Sunlight lost to shade | 6% | 300th most |
| Median roof size | 238 m² | 251st largest |
| Electricity rate | 11.3¢ | 738th highest |
| Payback | 16.9 yrs | 754th fastest |
| Grid carbon | 696 kg/MWh | 256th 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.
| City | Sun hrs | Rate | Payback |
|---|---|---|---|
| Kailua-Kona, HI | 1,253 | 42.1¢ | 4.5 yrs |
| Bradford, PA | 1,226 | 18.1¢ | 10.6 yrs |
| Gresham, OR | 1,257 | 12.4¢ | 15.4 yrs |
| Portland, OR | 1,258 | 12.4¢ | 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.