Peak sun hours in Vermont
Vermont averages 3.8 peak sun hours a day across the year, 48th of the 50 states. At that figure a 400-watt panel produces about 1.17 kWh a day after real-world losses, and covering the 900 kWh average US bill takes about 26 panels. Burlington, the state's biggest city, sits a little under the statewide figure at 3.7 hours, so 3.8 is the midpoint of a spread that leans away from the largest population centre.
cloudy-country sun: 3.8 of a possible ~6.5 hours
Panel counts for Vermont bills
Computed at Vermont's 3.8 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 | Vermont | System size | US average |
|---|---|---|---|
| 500 kWh/mo | 15 panels | 6 kW | 12 panels |
| 750 kWh/mo | 22 panels | 8.8 kW | 18 panels |
| 900 kWh/mo | 26 panels | 10.4 kW | 22 panels |
| 1,000 kWh/mo | 29 panels | 11.6 kW | 24 panels |
| 1,500 kWh/mo | 43 panels | 17.2 kW | 36 panels |
| 2,000 kWh/mo | 57 panels | 22.8 kW | 48 panels |
What 3.8 hours means in practice
Vermont is at the cloudy end of the table: 48th of 50 at 3.8 peak sun hours, 16% under the national average. Covering the 900 kWh average bill takes 26 panels here against 22 nationally. Solar still works at this latitude and cloud cover, and panels run cooler here, which claws a little of it back.
How a Vermont year is shaped
The 3.8-hour figure is an annual average, and no month is average. These are the twelve monthly means for Vermont from NASA's 2001-2020 solar climatology, each as a share of the state's own annual mean, with that share applied to the 3.8-hour planning figure. July and December are marked.
| Month | Share of the annual average | Peak sun hours (est.) |
|---|---|---|
| January | 42% | 1.6 |
| February | 65% | 2.5 |
| March | 97% | 3.7 |
| April | 125% | 4.8 |
| May | 145% | 5.5 |
| June | 158% | 6.0 |
| July | 161% | 6.1 |
| August | 143% | 5.4 |
| September | 115% | 4.4 |
| October | 69% | 2.6 |
| November | 45% | 1.7 |
| December | 32% | 1.2 |
Vermont's light is front-loaded into summer. July holds 161% of the annual average against December's 32%, 5 to one, and the four strongest months carry 51% of the year. Read across the table: 6.1 hours a day in July, about 1.2 in December. The annual average is honest arithmetic and thin planning, because most of the energy shows up in the months you need heating least.
Half the Vermont calendar sits above the annual average and half below: April through September are the six months that beat it, carrying 71% of the year's light. April is already worth about 4.8 hours a day, so the productive half of the year starts earlier than most people expect.
Bills here are small, which changes the shape of the whole decision: EIA put the average Vermont household at 574 kWh a month in 2024, 33% under the national 863 and among the lowest in the country. 17 panels cover it across a year, and 51 would be needed to cover it from December sun alone, 3.0 times as many. A gap that wide is what pushes people here onto net metering rather than a battery bank.
Vermont is small enough, or flat enough, that the sun barely varies across it: the 4 grid cells sampled here span only 5%, south to north. The statewide 3.8 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 Vermont bill
| EIA, 2024 residential averages | Vermont | United States |
|---|---|---|
| Average home's monthly use | 574 kWh | 863 kWh |
| Price per kilowatt-hour | 21.9¢ | 16.48¢ |
| Average monthly bill | $125.66 | $142.26 |
| One 400W panel, a year's output | 427 kWh | 506 kWh |
| What that output displaces | $94 | $83 |
Vermont pays 21.9¢ a kilowatt-hour, 10th highest in the country and 33% over the national 16.48¢. A single 400-watt panel therefore displaces about $94 of electricity a year here. Prices above the national line do more for a solar case than an extra half hour of sun does, because the sun sets the numerator and the rate sets what it is worth.
Which is why the sun ranking undersells Vermont. It places 48th of fifty for sunlight and 12th for what a panel actually earns, a jump of 36 places, and the second number is the one that shows up on a bill. Compare it with a state that gets similar sun: Washington gets the same sun (3.8 hours to Vermont's 3.8) and pays 11.9¢ against 21.9¢, so one panel is worth about $43 more a year in Vermont than in Washington.
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; 21.9¢ is every Vermont 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 Vermont?
About 26 400-watt panels (10.4 kW) for the 900 kWh a month an average US home uses, at Vermont's 3.8 peak sun hours. For the average Vermont home specifically, which EIA measured at 574 kWh a month in 2024, it is 17. Your own bill is the variable that matters, and the calculator takes any figure.
Is 3.8 peak sun hours good for solar?
It is below the 4.5-hour national average but far from disqualifying. Panel counts run about 18% 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 Vermont?
About $94. One 400-watt panel at Vermont's 3.8 peak sun hours makes roughly 427 kWh a year after the 0.77 derate, and Vermont residential electricity averaged 21.9¢ a kilowatt-hour in 2024 (EIA), which puts Vermont 12th of the 50 states on this measure against 48th 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 Vermont?
Yes, by a factor of 5 here. NASA's 2001-2020 climatology puts Vermont's July at 161% of the annual average and December at 32%, so the 3.8-hour figure on this page is the midpoint of a curve running from roughly 6.1 hours a day down to 1.2. Grid-tied homes bank the summer surplus as credit; off-grid designs have to size for the trough, and in Vermont that means 51 panels for an average local bill instead of 17.