Peak sun hours in Missouri
Missouri averages 4.6 peak sun hours a day across the year, 22nd of the 50 states. At that figure a 400-watt panel produces about 1.42 kWh a day after real-world losses, and covering the 900 kWh average US bill takes about 21 panels. Kansas City, the state's biggest city, runs slightly ahead of the statewide figure at 4.8 hours; treat 4.6 as the midpoint of a real spread rather than a local reading.
solid mid-pack sun: 4.6 of a possible ~6.5 hours
Panel counts for Missouri bills
Computed at Missouri's 4.6 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 | Missouri | System size | US average |
|---|---|---|---|
| 500 kWh/mo | 12 panels | 4.8 kW | 12 panels |
| 750 kWh/mo | 18 panels | 7.2 kW | 18 panels |
| 900 kWh/mo | 21 panels | 8.4 kW | 22 panels |
| 1,000 kWh/mo | 24 panels | 9.6 kW | 24 panels |
| 1,500 kWh/mo | 35 panels | 14 kW | 36 panels |
| 2,000 kWh/mo | 47 panels | 18.8 kW | 48 panels |
What 4.6 hours means in practice
Missouri is mid-pack American sun: 22nd of 50 at 4.6 peak sun hours, within 2% of the national average. The 900 kWh average bill lands at 21 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 Missouri year is shaped
The 4.6-hour figure is an annual average, and no month is average. These are the twelve monthly means for Missouri from NASA's 2001-2020 solar climatology, each as a share of the state's own annual mean, with that share applied to the 4.6-hour planning figure. June and December are marked.
| Month | Share of the annual average | Peak sun hours (est.) |
|---|---|---|
| January | 52% | 2.4 |
| February | 69% | 3.2 |
| March | 92% | 4.2 |
| April | 118% | 5.4 |
| May | 134% | 6.2 |
| June | 153% | 7.0 |
| July | 150% | 6.9 |
| August | 132% | 6.1 |
| September | 113% | 5.2 |
| October | 82% | 3.8 |
| November | 58% | 2.7 |
| December | 46% | 2.1 |
The gap between Missouri's best month and its worst is 3.4 to one: June at 153% of the annual average, December at 46%, or about 7.0 hours a day against 2.1. Four months carry 47% of the year's light. A grid-tied system rides that out on net metering without anyone noticing.
Half the Missouri calendar sits above the annual average and half below: April through September are the six months that beat it, carrying 67% of the year's light. April is already worth about 5.4 hours a day, so the productive half of the year starts earlier than most people expect.
Set that against what Missouri homes actually draw. EIA measured 1,001 kWh a month for the average household here in 2024, 16% above the US figure, which is 24 panels at the annual average sun. Hold the same house to a December and the count goes to 52, 2.2 times higher. Net metering is what makes the first number the one that matters.
Missouri is more uniform than most. The 20 grid cells sampled across the state span 7%, sunniest in the southwest and dimmest in the north, which scales to about 4.8 hours against 4.4. Enough to notice on a production estimate, not enough to change which system you buy. Kansas City sits inside that band, not at the edge of it.
What that sun is worth on a Missouri bill
| EIA, 2024 residential averages | Missouri | United States |
|---|---|---|
| Average home's monthly use | 1,001 kWh | 863 kWh |
| Price per kilowatt-hour | 12.91¢ | 16.48¢ |
| Average monthly bill | $129.18 | $142.26 |
| One 400W panel, a year's output | 517 kWh | 506 kWh |
| What that output displaces | $67 | $83 |
Cheap power cuts the other way. Missouri residential electricity averaged 12.91¢ a kilowatt-hour in 2024, 22% under the national 16.48¢ and 14th cheapest in the country, so the same panel that offsets $83 a year at national rates offsets about $67 here. Nothing is wrong with the sun. There is just less money in each kilowatt-hour it makes.
Here the sun ranking flatters Missouri. 22nd of fifty for sunlight, but only 37th for what a panel earns in a year, a drop of 15 places, and the reason is entirely the price of the electricity being replaced. Alabama gets the same sun (4.6 hours to Missouri's 4.6) and pays 15.18¢ against 12.91¢, so one panel is worth about $12 less a year in Missouri than in Alabama.
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; 12.91¢ is every Missouri 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 Missouri?
About 21 400-watt panels (8.4 kW) for the 900 kWh a month an average US home uses, at Missouri's 4.6 peak sun hours. For the average Missouri home specifically, which EIA measured at 1,001 kWh a month in 2024, it is 24. Your own bill is the variable that matters, and the calculator takes any figure.
Is 4.6 peak sun hours good for solar?
It is solidly workable. Missouri 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 Missouri?
About $67. One 400-watt panel at Missouri's 4.6 peak sun hours makes roughly 517 kWh a year after the 0.77 derate, and Missouri residential electricity averaged 12.91¢ a kilowatt-hour in 2024 (EIA), which puts Missouri 37th of the 50 states on this measure against 22nd 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 Missouri?
Yes, by a factor of 3.4 here. NASA's 2001-2020 climatology puts Missouri's June at 153% of the annual average and December at 46%, so the 4.6-hour figure on this page is the midpoint of a curve running from roughly 7.0 hours a day down to 2.1. Grid-tied homes bank the summer surplus as credit; off-grid designs have to size for the trough, and in Missouri that means 52 panels for an average local bill instead of 24.