Solar panels in Lafayette, LA
Roofs in Lafayette get about 1,672 hours of usable sunlight a year — more than 70% 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 Lafayette → City averages are a starting point; your own roof's size, pitch and shading change the answer a lot.
What a typical Lafayette solar system costs
A 19-panel system (7.6 kW) is about right for an average Lafayette home using 10,800 kWh a year. It would produce roughly 10,801 kWh annually and offset 100% of that usage.
| System | Size | kWh/yr | Net cost | Saves/yr | Payback |
|---|---|---|---|---|---|
| 8 panels | 3.2 kW | 4,548 | $6,384 | $550 | 11.6 yrs |
| 12 panels | 4.8 kW | 6,822 | $9,576 | $825 | 11.6 yrs |
| 16 panels | 6.4 kW | 9,096 | $12,768 | $1,101 | 11.6 yrs |
| 20 panels | 8 kW | 11,370 | $15,960 | $1,324 | 12.1 yrs |
| 26 panels | 10.4 kW | 14,780 | $20,748 | $1,427 | 14.5 yrs |
How we worked this out for Lafayette
Every number on this page comes from these seven steps. Nothing is a national average — the sunlight figure is measured from Lafayette rooftops.
| # | Step | Result |
|---|---|---|
| 1 | What one panel makes here 400W ÷ 1000 × 1,672 sun hrs × 0.85 system losses |
568 kWh/yr |
| 2 | Panels needed to cover typical usage 10,800 kWh ÷ 568 kWh per panel |
19 panels |
| 3 | System size 19 panels × 400W |
7.60 kW |
| 4 | Annual production 7.60 kW × 1,672 hrs × 0.85 |
10,801 kWh/yr |
| 5 | Installed cost 7,600 W × $2.85 per watt, then −30% federal credit |
$15,162 |
| 6 | Annual saving 3,780 kWh used as generated × 12.1¢ + 7,021 kWh exported × 12.1¢ |
$1,307/yr |
| 7 | Payback $15,162 ÷ $1,307 per year |
11.6 years |
Step 6 matters more than it looks. Only 35% of what a system this size produces in Lafayette is used the moment it is generated; the other 7,021 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 — 11.6 years against the 11.6 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, 12.1¢/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 Lafayette gets 1,672 sun hours
That figure comes from Google's analysis of real rooftops across Lafayette — 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 Lafayette reaches about 1,741 hours, roughly 4% better than typical.
The numbers behind this page
| Typical usable sunlight | 1,672 hrs/yr |
|---|---|
| Unshaded roof | 1,741 hrs/yr |
| Electricity rate (Louisiana avg) | 12.1¢/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 | 35% |
| Paid for exported power | full retail (net metering) |
| Rooftops sampled here | 10 |
| Google imagery from | 2023 |
When Lafayette actually produces
Annual totals hide the thing that catches people out: 32% of Lafayette's yearly sunlight arrives in May–July, and just 17% across November–January.
| Month | Sun hrs | Share of year |
|---|---|---|
| Jan | 94 | |
| Feb | 114 | |
| Mar | 139 | |
| Apr | 163 | |
| May | 177 | |
| Jun | 182 | |
| Jul | 179 | |
| Aug | 168 | |
| Sep | 148 | |
| Oct | 122 | |
| Nov | 98 | |
| Dec | 88 |
Output is unusually steady — only about 2.1× between Jun and Dec. Lafayette 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 Lafayette's latitude, not separately measured, so treat the monthly figures as the shape of a typical year rather than a forecast.
How Lafayette compares to the other 788 cities
| Measure | Lafayette | Rank of 788 |
|---|---|---|
| Usable sunlight | 1,672 hrs | 233rd |
| Sunlight lost to shade | 4% | 519th most |
| Median roof size | 150 m² | 557th largest |
| Electricity rate | 12.1¢ | 700th highest |
| Payback | 11.6 yrs | 487th fastest |
| Grid carbon | 540 kg/MWh | 482nd dirtiest |
What actually stands out about Lafayette:
- Cheap electricity is the headwind. Louisiana power costs about 12.1¢/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 Lafayette's 1,672 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 |
|---|---|---|---|
| Florence, SC | 1,672 | 14.2¢ | 9.9 yrs |
| Charleston, SC | 1,670 | 14.2¢ | 10.3 yrs |
| College Station, TX | 1,674 | 15.1¢ | 9.3 yrs |
| Victoria, TX | 1,670 | 15.1¢ | 9.7 yrs |
Nearby cities
See all of Louisiana → statewide sunlight, rates, incentives and every city we've measured.
Lafayette solar questions
How many solar panels do I need in Lafayette?
About 19 panels for an average home using 10,800 kWh a year. Lafayette roofs get 1,672 usable sun hours, so each 400W panel produces roughly 568 kWh annually. A typical Lafayette roof fits about 45 panels, so roof space is unlikely to be your limit.
Is solar worth it in Lafayette?
At 12.1¢/kWh and 1,672 sun hours, a typical system pays for itself in about 11.6 years and returns roughly $17,509 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 Lafayette?
A 7.6 kW system costs about $21,660 before incentives and $15,162 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 Louisiana 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.