Performance and output

Snow loss estimator, Northeast

Enter your snowfall, roof tilt, mounting setup, and removal habits. Get an annual kWh and dollar loss estimate built for Northeast winters.

Your system and winter

1 Project details Optional
Shown on your exported report. Leave blank to skip.
2 Your system
Use your system's rated annual output before any snow loss.
Northeast rates run higher than the US average, often $0.20 to $0.30.
3 Your winter conditions
Boston averages around 48in, Buffalo around 95in, Burlington VT around 80in.
Steeper tilt sheds snow faster. Most pitched roofs run 20 to 40 degrees.
4 Mounting and upkeep
More clearance under the panels lets slid snow fall away instead of piling up.
A raised frame edge can catch and hold snow slightly longer.
Manual or heated clearing recovers output that would otherwise sit under snow.

How it works

Three steps to a snow loss number

Step 1

Look up your local snowfall average

NOAA climate normals give a reliable annual snowfall figure for most Northeast cities and towns. If you're also weighing latitude effects, check the seasonal output by latitude tool alongside this one.

Step 2

Check your tilt and mounting setup

A steep roof or a ground mount with clearance sheds snow much faster than a flat, low-profile array. These two factors do more to change your result than snowfall alone.

Step 3

Decide on a removal strategy

Occasional manual clearing or a heated cable system meaningfully cuts your loss. Compare your result against the cold climate efficiency gain calculator to see the offsetting winter benefit.

Understanding snow loss in the Northeast

Why snowfall alone doesn't tell the whole story

A typical Northeast system with 60 inches of annual snowfall, a 30 degree tilt, and no snow removal loses around 3% to 4% of annual output. That number changes fast once you factor in tilt, mounting height, and whether anyone ever clears the panels. Two homes with identical snowfall can see very different results based on these choices. A DOE assessment of 75 federal PV systems treats snow cover as an unmodeled measurable loss, meaning it appears fully as underperformance rather than being absorbed into baseline projections.

Tilt does more work than most people expect

A steep 40 to 45 degree tilt sheds snow within a day or two of a storm, while a flat roof under 15 degrees can hold snow for a week or more, since gravity does far less of the work. If you're weighing a mounting angle decision for a new install, the array tilt angle optimizer balances snow shedding against summer output.

When manual clearing and heated cables make sense

For most ground-level or easily reached systems, occasional manual clearing after major storms can cut snow-related loss by roughly 40%. Never clear a roof-mounted array yourself if it requires climbing on an icy roof, since the fall risk outweighs the modest output gain. OSHA's own winter weather safety guidance lists falls as the leading cause of injury during rooftop snow removal, and recommends using ground-based tools like snow rakes rather than climbing onto a snow-covered roof whenever it's possible to avoid. Heated cables can cut snow loss by 80% or more, but they draw their own electricity and add hardware cost, so they tend to pay off best on systems with heavy snowfall and no safe manual option.

How this compares to other cold-climate factors

Snow loss is separate from the efficiency gain cold panels get from lower operating temperatures. Check the cold climate efficiency gain calculator to see how that offsetting effect plays into your winter numbers.

What to do with this number next

Compare your Northeast estimate against the Midwest or Mountain West tools if you're evaluating a move, or run the output vs usage gap analyzer to see how winter shortfalls line up against your household usage. When output drops to zero in a storm, the winter storm backup planning calculator sizes the backup you need.

Questions

Frequently asked

A typical Northeast system with 60 inches of annual snowfall, a 30 degree tilt, and no snow removal loses around 3% to 4% of annual output. An 11,000 kWh/year system loses roughly 385 kWh a year under those conditions.

Yes, significantly. A steep 40 to 45 degree tilt sheds snow within a day or two of a storm, while a flat roof under 15 degrees can hold snow for a week or more, since gravity does far less of the work.

For most ground-level or easily reached systems, occasional manual clearing after major storms can cut snow-related loss by roughly 40%. Never clear a roof-mounted array yourself if it requires climbing on an icy roof, since the fall risk outweighs the modest output gain.

Heated cables can cut snow loss by 80% or more, but they draw their own electricity and add hardware cost. They tend to make the most sense on systems with heavy snowfall, low tilt, and no safe way to clear snow manually.

Related tools

Keep exploring your winter output

Snow loss estimator, Midwest Snow loss estimator, Mountain West Snow loss estimator, Canada Cold climate efficiency gain Seasonal output by latitude Output vs usage gap analyzer Real world vs nameplate output gap All performance and output tools