Peak sun hours in Louisiana
Louisiana averages 4.9 peak sun hours a day across the year, 14th of the 50 states. At that figure a 400-watt panel produces about 1.51 kWh a day after real-world losses, and covering the 900 kWh average US bill takes about 20 panels. New Orleans, the state's biggest city, sits at 4.9 hours, close enough to the statewide figure to use either, though elevation and distance from water still move the number street by street.
solid mid-pack sun: 4.9 of a possible ~6.5 hours
Panel counts for Louisiana bills
Computed at Louisiana's 4.9 hours with 400W panels and the 0.77 derate; the US-average column shows what the same bill takes at 4.5 hours, so you can see what your state's sun is worth in hardware.
| Monthly usage | Louisiana | System size | US average |
|---|---|---|---|
| 500 kWh/mo | 11 panels | 4.4 kW | 12 panels |
| 750 kWh/mo | 17 panels | 6.8 kW | 18 panels |
| 900 kWh/mo | 20 panels | 8 kW | 22 panels |
| 1,000 kWh/mo | 22 panels | 8.8 kW | 24 panels |
| 1,500 kWh/mo | 33 panels | 13.2 kW | 36 panels |
| 2,000 kWh/mo | 44 panels | 17.6 kW | 48 panels |
What 4.9 hours means in practice
Louisiana is mid-pack American sun: 14th of 50 at 4.9 peak sun hours, within 9% of the national average. The 900 kWh average bill lands at 20 panels against 22 nationally. At this tier the resource neither makes nor breaks the project, which is what the rate and the seasonal spread below are for.
How a Louisiana year is shaped
The 4.9-hour figure is an annual average, and no month is average. These are the twelve monthly means for Louisiana from NASA's 2001-2020 solar climatology, each as a share of the state's own annual mean, with that share applied to the 4.9-hour planning figure. June and December are marked.
| Month | Share of the annual average | Peak sun hours (est.) |
|---|---|---|
| January | 61% | 3.0 |
| February | 72% | 3.5 |
| March | 98% | 4.8 |
| April | 120% | 5.9 |
| May | 133% | 6.5 |
| June | 135% | 6.6 |
| July | 129% | 6.3 |
| August | 122% | 6.0 |
| September | 110% | 5.4 |
| October | 93% | 4.6 |
| November | 71% | 3.5 |
| December | 55% | 2.7 |
Louisiana has a shallow year by American standards, 2.4 to one between June and December, which still returns 55% of the annual average, around 2.7 hours a day. Only 43% of the light lands in the four best months, against 6.6 hours at the June peak. Nothing here is seasonal enough to change how you size a grid-tied array.
Half the Louisiana calendar sits above the annual average and half below: April through September are the six months that beat it, carrying 62% of the year's light. April is already worth about 5.9 hours a day, so the productive half of the year starts earlier than most people expect.
That matters most where homes are hungry, and Louisiana's are: EIA put the average household here at 1,202 kWh a month in 2024, 39% above the national 863. Covering that bill on an annual average takes 27 panels. Covering it inside a Louisiana December, with no grid and no bank of summer credit, takes 48, about 1.8 times as many. Grid-tied you never see the difference. Off-grid it is the whole design.
Louisiana is more uniform than most. The 13 grid cells sampled across the state span 6%, sunniest in the south and dimmest in the northwest, which scales to about 5.0 hours against 4.8. Enough to notice on a production estimate, not enough to change which system you buy. New Orleans sits inside that band, not at the edge of it.
What that sun is worth on a Louisiana bill
| EIA, 2024 residential averages | Louisiana | United States |
|---|---|---|
| Average home's monthly use | 1,202 kWh | 863 kWh |
| Price per kilowatt-hour | 11.73¢ | 16.48¢ |
| Average monthly bill | $140.96 | $142.26 |
| One 400W panel, a year's output | 551 kWh | 506 kWh |
| What that output displaces | $65 | $83 |
Louisiana has some of the cheapest electricity in the United States, 11.73¢ a kilowatt-hour in 2024 against a national 16.48¢, 4th cheapest of the fifty. That is 29% less value in every kilowatt-hour a panel produces: about $65 a year from one 400-watt panel where the national figure is $83. Sun is not this state's constraint on solar. The rate it displaces is.
Here the sun ranking flatters Louisiana. 14th of fifty for sunlight, but only 43rd for what a panel earns in a year, a drop of 29 places, and the reason is entirely the price of the electricity being replaced. Georgia gets the same sun (4.9 hours to Louisiana's 4.9) and pays 14.08¢ against 11.73¢, so one panel is worth about $13 less a year in Louisiana than in Georgia.
Two warnings on those dollar figures. They are displaced electricity and nothing else: no install cost, no incentive, no financing, and no assumption about how your utility settles a surplus, which is the single biggest unknown in the sum. And a state average hides the utility you are actually on; 11.73¢ is every Louisiana residential customer averaged together, and neighbouring territories can differ by more than the gap between two states in the ranking.
Getting a number for your address
For a location-exact figure, run your address through NREL's free PVWatts; it uses measured weather for your grid cell and will also model roof tilt and direction, which statewide numbers cannot. Then compare its annual kWh against a quote's promise before you sign anything.
Questions people ask
How many solar panels do I need in Louisiana?
About 20 400-watt panels (8 kW) for the 900 kWh a month an average US home uses, at Louisiana's 4.9 peak sun hours. For the average Louisiana home specifically, which EIA measured at 1,202 kWh a month in 2024, it is 27. Your own bill is the variable that matters, and the calculator takes any figure.
Is 4.9 peak sun hours good for solar?
It is solidly workable. Louisiana sits near the national average of 4.5 hours, so panel counts here match the US-typical figures, and project economics turn on your utility's rates and net-metering terms rather than on the sun.
How much is one solar panel worth a year in Louisiana?
About $65. One 400-watt panel at Louisiana's 4.9 peak sun hours makes roughly 551 kWh a year after the 0.77 derate, and Louisiana residential electricity averaged 11.73¢ a kilowatt-hour in 2024 (EIA), which puts Louisiana 43rd of the 50 states on this measure against 14th on sunlight alone. That figure is displaced electricity only. It says nothing about install cost, incentives, or how your utility settles a surplus.
Do peak sun hours change with the seasons in Louisiana?
Yes, by a factor of 2.4 here. NASA's 2001-2020 climatology puts Louisiana's June at 135% of the annual average and December at 55%, so the 4.9-hour figure on this page is the midpoint of a curve running from roughly 6.6 hours a day down to 2.7. Grid-tied homes bank the summer surplus as credit; off-grid designs have to size for the trough, and in Louisiana that means 48 panels for an average local bill instead of 27.