Peak sun hours in Connecticut
Connecticut averages 4 peak sun hours a day across the year, 37th of the 50 states. At that figure a 400-watt panel produces about 1.23 kWh a day after real-world losses, and covering the 900 kWh average US bill takes about 25 panels. Hartford, the state's biggest city, sits at 4 hours, close enough to the statewide figure to use either, though elevation and distance from water still move the number street by street.
modest sun: 4 of a possible ~6.5 hours
Panel counts for Connecticut bills
Computed at Connecticut's 4 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 | Connecticut | System size | US average |
|---|---|---|---|
| 500 kWh/mo | 14 panels | 5.6 kW | 12 panels |
| 750 kWh/mo | 21 panels | 8.4 kW | 18 panels |
| 900 kWh/mo | 25 panels | 10 kW | 22 panels |
| 1,000 kWh/mo | 27 panels | 10.8 kW | 24 panels |
| 1,500 kWh/mo | 41 panels | 16.4 kW | 36 panels |
| 2,000 kWh/mo | 54 panels | 21.6 kW | 48 panels |
What 4 hours means in practice
Connecticut runs 11% below the national solar average, 37th of 50 at 4 hours. That is workable sun, not bad sun: the 900 kWh bill takes 25 panels here versus 22 nationally, 3 more. Germany built the world's densest solar fleet on worse.
How a Connecticut year is shaped
The 4-hour figure is an annual average, and no month is average. These are the twelve monthly means for Connecticut 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-hour planning figure. July and December are marked.
| Month | Share of the annual average | Peak sun hours (est.) |
|---|---|---|
| January | 47% | 1.9 |
| February | 69% | 2.8 |
| March | 96% | 3.8 |
| April | 124% | 5.0 |
| May | 140% | 5.6 |
| June | 152% | 6.1 |
| July | 155% | 6.2 |
| August | 137% | 5.5 |
| September | 112% | 4.5 |
| October | 75% | 3.0 |
| November | 52% | 2.1 |
| December | 39% | 1.6 |
Best to worst in Connecticut is 4 to one: July at 155% of the annual average, December at 39%, 6.2 hours a day against 1.6. Four months hold 49% of the year's light. A grid-tied array absorbs that on net metering; a battery bank has to be sized for the December end of it.
Half the Connecticut calendar sits above the annual average and half below: April through September are the six months that beat it, carrying 68% of the year's light. April is already worth about 5.0 hours a day, so the productive half of the year starts earlier than most people expect.
Connecticut homes are light users by national standards, 695 kWh a month on EIA's 2024 average against 863 nationally, 19% below. That is only 19 panels at the annual figure, which is why modest arrays go a long way here. Carrying the same house through December on its own would take 48, 2.5 times more.
Connecticut is small enough, or flat enough, that the sun barely varies across it: the 3 grid cells sampled here span only 3%, east to west. The statewide 4 figure is a good description of the whole state, which is not something you can say about Texas or Oregon. Shade and roof pitch will move your output far more than address does.
What that sun is worth on a Connecticut bill
| EIA, 2024 residential averages | Connecticut | United States |
|---|---|---|
| Average home's monthly use | 695 kWh | 863 kWh |
| Price per kilowatt-hour | 28.75¢ | 16.48¢ |
| Average monthly bill | $199.66 | $142.26 |
| One 400W panel, a year's output | 450 kWh | 506 kWh |
| What that output displaces | $129 | $83 |
The rate matters more here than the sun does. Connecticut residential power averaged 28.75¢ a kilowatt-hour in 2024, 74% over the national 16.48¢ and 4th highest of the fifty states, so a 400-watt panel offsets about $129 of electricity a year despite Connecticut sitting 37th on sunlight. A cheap-power state would need most of another peak sun hour to match that.
Which is why the sun ranking undersells Connecticut. It places 37th of fifty for sunlight and 5th for what a panel actually earns, a jump of 32 places, and the second number is the one that shows up on a bill. Compare it with a state that gets similar sun: West Virginia gets less sun (3.9 hours to Connecticut's 4) and pays 15.07¢ against 28.75¢, so one panel is worth about $63 more a year in Connecticut than in West Virginia.
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; 28.75¢ is every Connecticut 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 Connecticut?
About 25 400-watt panels (10 kW) for the 900 kWh a month an average US home uses, at Connecticut's 4 peak sun hours. For the average Connecticut home specifically, which EIA measured at 695 kWh a month in 2024, it is 19. Your own bill is the variable that matters, and the calculator takes any figure.
Is 4 peak sun hours good for solar?
It is below the 4.5-hour national average but far from disqualifying. Panel counts run about 13% higher here for the same bill, and the December trough measured above deserves respect in any off-grid plan. Grid-tied systems ride through it on net metering.
How much is one solar panel worth a year in Connecticut?
About $129. One 400-watt panel at Connecticut's 4 peak sun hours makes roughly 450 kWh a year after the 0.77 derate, and Connecticut residential electricity averaged 28.75¢ a kilowatt-hour in 2024 (EIA), which puts Connecticut 5th of the 50 states on this measure against 37th 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 Connecticut?
Yes, by a factor of 4 here. NASA's 2001-2020 climatology puts Connecticut's July at 155% of the annual average and December at 39%, so the 4-hour figure on this page is the midpoint of a curve running from roughly 6.2 hours a day down to 1.6. Grid-tied homes bank the summer surplus as credit; off-grid designs have to size for the trough, and in Connecticut that means 48 panels for an average local bill instead of 19.