VT · solar resource

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 at 3.7 hours, close to the statewide figure, though microclimates and elevation still move the local number.

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 usageVermontSystem sizeUS average
500 kWh/mo15 panels6 kW12 panels
750 kWh/mo22 panels8.8 kW18 panels
900 kWh/mo26 panels10.4 kW22 panels
1,000 kWh/mo29 panels11.6 kW24 panels
1,500 kWh/mo43 panels17.2 kW36 panels
2,000 kWh/mo57 panels22.8 kW48 panels

Your bill, Vermont sun

From your bill; how to find it.
System size (DC)
Roof area, with racking gaps
Expected output per month

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 (panels run cooler, which claws a little back), but the December trough is deep, so the difference between a grid-tied system that banks summer credits and an off-grid system that must survive winter is bigger here than anywhere in the Sun Belt.

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. Your bill is the variable that matters: the table on this page covers 500 to 2,000 kWh, 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-January trough deserves respect in any off-grid plan. Grid-tied systems ride through it on net metering.

Do peak sun hours change with the seasons in Vermont?

Yes, everywhere: the figure on this page is the annual average of a curve that peaks in June and bottoms out in December. At Vermont’s latitude and cloud cover the winter trough is deep, often a third of the summer figure or less. Grid-tied homes bank summer overproduction as credit; off-grid designs must size for the trough, not the average.

Elsewhere on the map