Solar panels in Bellevue, WA
Roofs in Bellevue get about 1,175 hours of usable sunlight a year — less than 84% 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 Bellevue → City averages are a starting point; your own roof's size, pitch and shading change the answer a lot.
What a typical Bellevue solar system costs
A 28-panel system (11.2 kW) is about right for an average Bellevue home using 10,800 kWh a year. It would produce roughly 11,186 kWh annually and offset 100% of that usage.
| System | Size | kWh/yr | Net cost | Saves/yr | Payback |
|---|---|---|---|---|---|
| 8 panels | 3.2 kW | 3,196 | $6,384 | $361 | 17.7 yrs |
| 12 panels | 4.8 kW | 4,794 | $9,576 | $542 | 17.7 yrs |
| 16 panels | 6.4 kW | 6,392 | $12,768 | $722 | 17.7 yrs |
| 20 panels | 8 kW | 7,990 | $15,960 | $903 | 17.7 yrs |
| 26 panels | 10.4 kW | 10,387 | $20,748 | $1,174 | 17.7 yrs |
How we worked this out for Bellevue
Every number on this page comes from these seven steps. Nothing is a national average — the sunlight figure is measured from Bellevue rooftops.
| # | Step | Result |
|---|---|---|
| 1 | What one panel makes here 400W ÷ 1000 × 1,175 sun hrs × 0.85 system losses |
400 kWh/yr |
| 2 | Panels needed to cover typical usage 10,800 kWh ÷ 400 kWh per panel |
28 panels |
| 3 | System size 28 panels × 400W |
11.20 kW |
| 4 | Annual production 11.20 kW × 1,175 hrs × 0.85 |
11,186 kWh/yr |
| 5 | Installed cost 11,200 W × $2.85 per watt, then −30% federal credit |
$22,344 |
| 6 | Annual saving 3,780 kWh used as generated × 11.3¢ + 7,406 kWh exported × 11.3¢ |
$1,231/yr |
| 7 | Payback $22,344 ÷ $1,231 per year |
18.1 years |
Step 6 matters more than it looks. Only 34% of what a system this size produces in Bellevue is used the moment it is generated; the other 7,406 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 — 17.7 years against the 18.1 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 Bellevue gets 1,175 sun hours
That figure comes from Google's analysis of real rooftops across Bellevue — 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 Bellevue reaches about 1,312 hours, roughly 12% better than typical.
The numbers behind this page
| Typical usable sunlight | 1,175 hrs/yr |
|---|---|
| Unshaded roof | 1,312 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 | 12 |
| Google imagery from | 2024 |
When Bellevue actually produces
Annual totals hide the thing that catches people out: 40% of Bellevue's yearly sunlight arrives in May–July, and just 10% across November–January.
| Month | Sun hrs | Share of year |
|---|---|---|
| Jan | 41 | |
| Feb | 62 | |
| Mar | 92 | |
| Apr | 125 | |
| May | 150 | |
| Jun | 161 | |
| Jul | 155 | |
| Aug | 134 | |
| Sep | 104 | |
| Oct | 71 | |
| Nov | 46 | |
| Dec | 35 |
That is a severe seasonal swing — Bellevue produces roughly 4.6× 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 Bellevue's latitude, not separately measured, so treat the monthly figures as the shape of a typical year rather than a forecast.
How Bellevue compares to the other 788 cities
| Measure | Bellevue | Rank of 788 |
|---|---|---|
| Usable sunlight | 1,175 hrs | 664th |
| Sunlight lost to shade | 10% | 59th most |
| Median roof size | 239 m² | 246th largest |
| Electricity rate | 11.3¢ | 730th highest |
| Payback | 18.1 yrs | 762nd fastest |
| Grid carbon | 696 kg/MWh | 227th dirtiest |
What actually stands out about Bellevue:
- Shading is a real problem here. Bellevue loses 10% of its potential sunlight to trees, chimneys and neighbouring buildings — the 59th-worst of the 788 cities measured. Panel placement matters more here than in most places, and a roof survey is worth more than a phone quote.
- Dimmer than the rest of Washington. Bellevue roofs get 6% less usable sunlight than the typical Washington city we've measured — statewide averages will overstate what you can expect here.
- 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 Bellevue's 1,175 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 |
|---|---|---|---|
| Astoria, OR | 1,152 | 12.4¢ | 16.6 yrs |
| State College, PA | 1,201 | 18.1¢ | 11 yrs |
| Bradford, PA | 1,226 | 18.1¢ | 10.6 yrs |
| Kailua-Kona, HI | 1,253 | 42.1¢ | 4.5 yrs |
Nearby cities
See all of Washington → statewide sunlight, rates, incentives and every city we've measured.
Bellevue solar questions
How many solar panels do I need in Bellevue?
About 28 panels for an average home using 10,800 kWh a year. Bellevue roofs get 1,175 usable sun hours, so each 400W panel produces roughly 400 kWh annually. A typical Bellevue roof fits about 67 panels, so roof space is unlikely to be your limit.
Is solar worth it in Bellevue?
At 11.3¢/kWh and 1,175 sun hours, a typical system pays for itself in about 18.1 years and returns roughly $8,439 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 Bellevue?
A 11.2 kW system costs about $31,920 before incentives and $22,344 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.