Performance and output

Snow loss estimator, Canada

Enter your snowfall in centimetres, pick your region, and add your tilt and removal setup. Get an annual kWh loss estimate built for Canadian 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.
Rates vary widely by province. Check a recent utility bill for your figure.
3 Your winter conditions
Each region has different wind, thaw, and snow patterns baked into this factor.
Toronto averages around 120cm, Winnipeg around 115cm, Montreal around 210cm, St. John's around 322cm.
Steeper tilt sheds snow faster. Most pitched roofs run 25 to 40 degrees.
4 Mounting and upkeep
More clearance under the panels lets slid snow fall away instead of piling up.
Manual or heated clearing recovers output that would otherwise sit under snow.

How it works

Four steps to a snow loss number

Step 1

Pick your region

Canada spans a wide range of winter climates, from mild coastal BC to sustained deep cold in the North. Your region sets the biggest swing in this estimate before snowfall even factors in.

Step 2

Enter your local snowfall in centimetres

Environment Canada climate normals list annual snowfall for most cities and towns. Use your specific location rather than a provincial average when you can.

Step 3

Set your tilt angle

A steeper roof sheds snow faster regardless of region. If you're deciding on a mounting angle, the seasonal output by latitude tool helps balance snow shedding against summer output.

Step 4

Add your mounting and removal plan

Combine mounting height and removal habits for a final number. Compare the offsetting gain from cold temperatures using the cold climate efficiency calculator.

Understanding snow loss across Canada

Why region matters more than snowfall alone

A typical Ontario or Quebec system with 150cm of annual snowfall, a 35 degree tilt, and no snow removal loses around 3.3% of annual output. A 10,000 kWh/year system loses roughly 328 kWh a year under those conditions, with Northern regions losing more and Coastal BC losing less. Two locations with identical snowfall totals can post very different loss numbers once regional wind and thaw patterns come into play. A DOE assessment of federal solar installations treats snow cover as a measurable loss deliberately excluded from baseline models, so it shows up fully as underperformance when it occurs.

How each region's climate shapes the result

Coastal BC sees milder temperatures and frequent winter thaws that clear snow quickly, while Northern regions stay below freezing for months with almost no natural melting. The Prairies get strong, consistent wind that blows snow off panels even in deep cold, which partly offsets their harsh winters. This is why the Prairies often see less snow loss than their snowfall totals alone would suggest.

Why Atlantic Canada often runs higher

Often yes, Atlantic Canada does tend to lose more than other regions. Coastal storms in the region tend to bring wetter, heavier snow that sticks to panels more than the drier snow common further inland, and the region doesn't get the same steady wind clearing the Prairies benefit from. Natural Resources Canada's climate atlas confirms this coastal pattern directly, noting that precipitation along the Atlantic tends toward a rain and snow mix while drier, more purely snow-dominated conditions take over further inland.

Deciding if a heated cable system is worth it

It depends heavily on region. Northern and Atlantic systems with heavy snowfall and limited natural clearing see the most benefit, while Prairie and Coastal BC systems often get enough natural help from wind or thaw cycles that a heated system adds cost without much extra output. The total cost of ownership calculator can help weigh that added equipment cost against the output it actually recovers for your specific region.

What to do with this number next

Compare your result against a specific US region using the Northeast or Midwest tools, or run the output vs usage gap analyzer to see how winter output lines up with your household's usage. The winter storm backup planning calculator sizes the backup for the days that output disappears.

Questions

Frequently asked

A typical Ontario or Quebec system with 150cm of annual snowfall, a 35 degree tilt, and no snow removal loses around 3.3% of annual output. A 10,000 kWh/year system loses roughly 328 kWh a year under those conditions, with Northern regions losing more and Coastal BC losing less.

Coastal BC sees milder temperatures and frequent winter thaws that clear snow quickly, while Northern regions stay below freezing for months with almost no natural melting. The Prairies get strong, consistent wind that blows snow off panels even in deep cold, which partly offsets their harsh winters.

Often yes. Coastal storms in Atlantic Canada tend to bring wetter, heavier snow that sticks to panels more than the drier snow common further inland, and the region doesn't get the same steady wind clearing the Prairies benefit from.

It depends heavily on region. Northern and Atlantic systems with heavy snowfall and limited natural clearing see the most benefit, while Prairie and Coastal BC systems often get enough natural help from wind or thaw cycles that a heated system adds cost without much extra output.

Related tools

Keep exploring your winter output

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