Solar panels in Greenville, SC
Roofs in Greenville get about 1,418 hours of usable sunlight a year — less than 65% 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 Greenville → City averages are a starting point; your own roof's size, pitch and shading change the answer a lot.
What a typical Greenville solar system costs
A 23-panel system (9.2 kW) is about right for an average Greenville home using 10,800 kWh a year. It would produce roughly 11,089 kWh annually and offset 100% of that usage.
| System | Size | kWh/yr | Net cost | Saves/yr | Payback |
|---|---|---|---|---|---|
| 8 panels | 3.2 kW | 3,857 | $6,384 | $548 | 11.7 yrs |
| 12 panels | 4.8 kW | 5,785 | $9,576 | $822 | 11.7 yrs |
| 16 panels | 6.4 kW | 7,714 | $12,768 | $1,095 | 11.7 yrs |
| 20 panels | 8 kW | 9,642 | $15,960 | $1,369 | 11.7 yrs |
| 26 panels | 10.4 kW | 12,535 | $20,748 | $1,595 | 13 yrs |
How we worked this out for Greenville
Every number on this page comes from these seven steps. Nothing is a national average — the sunlight figure is measured from Greenville rooftops.
| # | Step | Result |
|---|---|---|
| 1 | What one panel makes here 400W ÷ 1000 × 1,418 sun hrs × 0.85 system losses |
482 kWh/yr |
| 2 | Panels needed to cover typical usage 10,800 kWh ÷ 482 kWh per panel |
23 panels |
| 3 | System size 23 panels × 400W |
9.20 kW |
| 4 | Annual production 9.20 kW × 1,418 hrs × 0.85 |
11,089 kWh/yr |
| 5 | Installed cost 9,200 W × $2.85 per watt, then −30% federal credit |
$18,354 |
| 6 | Annual saving 3,780 kWh used as generated × 14.2¢ + 7,309 kWh exported × 14.2¢ |
$1,544/yr |
| 7 | Payback $18,354 ÷ $1,544 per year |
11.9 years |
Step 6 matters more than it looks. Only 34% of what a system this size produces in Greenville is used the moment it is generated; the other 7,309 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 — 11.7 years against the 11.9 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, 14.2¢/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 Greenville gets 1,418 sun hours
That figure comes from Google's analysis of real rooftops across Greenville — 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 Greenville reaches about 1,685 hours, roughly 19% better than typical.
The numbers behind this page
| Typical usable sunlight | 1,418 hrs/yr |
|---|---|
| Unshaded roof | 1,685 hrs/yr |
| Electricity rate (South Carolina avg) | 14.2¢/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 | 15 |
| Google imagery from | 2023 |
When Greenville actually produces
Annual totals hide the thing that catches people out: 34% of Greenville's yearly sunlight arrives in May–July, and just 15% across November–January.
| Month | Sun hrs | Share of year |
|---|---|---|
| Jan | 72 | |
| Feb | 92 | |
| Mar | 117 | |
| Apr | 141 | |
| May | 157 | |
| Jun | 163 | |
| Jul | 160 | |
| Aug | 147 | |
| Sep | 125 | |
| Oct | 99 | |
| Nov | 77 | |
| Dec | 67 |
Output is unusually steady — only about 2.5× between Jun and Dec. Greenville is close enough to the equator that seasonal variation is mild, which makes sizing a system considerably more predictable.
The annual total is measured from Google's rooftop imagery. Its split across months is calculated from solar geometry at Greenville's latitude, not separately measured, so treat the monthly figures as the shape of a typical year rather than a forecast.
How Greenville compares to the other 788 cities
| Measure | Greenville | Rank of 788 |
|---|---|---|
| Usable sunlight | 1,418 hrs | 512th |
| Sunlight lost to shade | 16% | 10th most |
| Median roof size | 212 m² | 321st largest |
| Electricity rate | 14.2¢ | 555th highest |
| Payback | 11.9 yrs | 517th fastest |
| Grid carbon | 649 kg/MWh | 349th dirtiest |
What actually stands out about Greenville:
- Shading is a real problem here. Greenville loses 16% of its potential sunlight to trees, chimneys and neighbouring buildings — the 10th-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 South Carolina. Greenville roofs get 13% less usable sunlight than the typical South Carolina city we've measured — statewide averages will overstate what you can expect here.
Cities with almost the same sunlight
These are the closest matches to Greenville's 1,418 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 |
|---|---|---|---|
| Somerville, MA | 1,418 | 30.1¢ | 5.6 yrs |
| Plymouth, MN | 1,418 | 14.8¢ | 11.4 yrs |
| Minneapolis, MN | 1,419 | 14.8¢ | 11.4 yrs |
| Annapolis, MD | 1,419 | 18.3¢ | 9.2 yrs |
Nearby cities
See all of South Carolina → statewide sunlight, rates, incentives and every city we've measured.
Greenville solar questions
How many solar panels do I need in Greenville?
About 23 panels for an average home using 10,800 kWh a year. Greenville roofs get 1,418 usable sun hours, so each 400W panel produces roughly 482 kWh annually. A typical Greenville roof fits about 60 panels, so roof space is unlikely to be your limit.
Is solar worth it in Greenville?
At 14.2¢/kWh and 1,418 sun hours, a typical system pays for itself in about 11.9 years and returns roughly $20,242 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 Greenville?
A 9.2 kW system costs about $26,220 before incentives and $18,354 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 South Carolina 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.