Solar Shading Analysis Software Canada: 2026 Guide

Canadian solar shading analysis is a winter problem wearing an annual disguise. At Canadian latitudes the sun sits below roughly 20 degrees at solar noon in late December, against 50 degrees or more in June. Because shadow length scales inversely with the tangent of solar altitude, the same chimney that casts a 2 metre shadow in summer casts something closer to 6 metres in midwinter. Any model that reports an annual shading percentage averages that concentrated loss across twelve months and hides it. This guide covers what shading analysis has to do differently in Canada, and which tools do it.

Short version. Solar shading analysis software for Canadian projects has to run 8,760 hourly steps at module level, because Canadian shading losses concentrate into the winter months when the sun is low and consumption is high. An annual percentage is not a useful output here. The tool also has to price the loss against the correct provincial net metering rule, since a shaded kilowatt-hour is worth roughly three times more in Ontario than in Manitoba.

The general methodology is covered in our solar shading analysis software guide. This page covers what changes at Canadian latitudes. For the wider platform comparison see best solar design software Canada.

The Geometry: Why Canadian Shadows Are Different

Shadow length from an obstruction of height h is approximately h divided by the tangent of the solar altitude angle. That relationship is not linear, and it turns punishing at low angles.

The bottom rows are the Canadian design problem. An obstruction that is irrelevant in July governs the array for much of the winter day, and the hours either side of noon are worse than noon itself.

The correct output is monthly. A shading report that cannot break loss down by month is not describing a Canadian installation.

Snow, And Why It Compounds

Snow on modules is not geometric shading. It blocks irradiance broadly across the module surface rather than casting a shadow from an obstruction, which makes it behave more like heavy soiling in the electrical model.

What matters for design is timing. Snow losses and low-sun shading losses land in the same months, so they compound rather than alternate. A tool that models geometric shading well and treats snow as a flat annual derate will produce a plausible annual number and a wrong winter profile.

Two design responses follow. Steeper tilt sheds snow faster and also improves winter sun capture, which is why Canadian tilt optimisation often lands steeper than a pure annual-yield calculation suggests. And where the array is already shaded in winter, the marginal value of clearing snow falls, because the modules would be underperforming regardless.

Pricing The Loss: Province Decides What Shading Costs

A shading loss is only as expensive as the energy it destroys, and Canadian export rates vary by more than three to one.

There is a subtlety worth carrying into customer conversations. A shaded kilowatt-hour that would have been self-consumed always costs full retail, regardless of province. A shaded kilowatt-hour that would have been exported costs only the export rate. So in Manitoba, shading that hits midday surplus is relatively cheap, while shading that hits morning or evening on-site demand is expensive. In Ontario the two converge.

That means the same physical obstruction has a different remediation budget depending on province and on which hours it affects. Tree trimming that pays in Ontario may not pay in Manitoba. Only an hourly model that knows the tariff can tell you which. Our best solar design software Canada guide covers the provincial libraries in full.

Inter-Row Spacing On Canadian Ground Mount

The traditional rule sizes row spacing to avoid shading at winter solstice. At Canadian latitudes that demands very wide rows and wastes a great deal of land, and on the Prairies where ground-mount is common the land is the project.

The better approach treats spacing as an optimisation. Simulate three or four candidate spacings across all 8,760 hours, price the resulting energy at the actual provincial rates, and compare marginal land and racking cost against marginal energy value. Accepting some winter-morning inter-row shading is frequently the correct answer, because those hours are low-value and the land saving is real.

That calculation cannot be done with a geometric rule or a solstice diagram. It needs a simulation engine and a tariff model in the same tool. Our PV yield simulation software guide covers the underlying methodology.

Worked Example: Chimney Shadow On A Toronto Rooftop

An illustrative calculation showing why the monthly profile matters, not a specific customer project. Inputs: 8 kW array, 1,150 kWh per kW specific yield, single 2 m chimney on the south slope, Ontario retail credit at $0.145.

The annual figure reads 5.5%, which sounds tolerable. The December figure is 23%. A customer who was told “about 5%” and then watches a December bill that barely moves has been misinformed, even though the annual number was accurate.

The second insight is the remediation maths. At $73 a year of lost value, trimming or relocating around the chimney has a small budget in Ontario. In Manitoba the same physical loss would be worth substantially less again. The honest recommendation is often to accept the shading and set expectations, rather than to sell a mitigation that does not pay.

Who Should Choose What

• Choose SurgePV if you want 8,760-hour module-level shading with provincial tariff libraries in the same tool, so losses are priced as well as computed.
• Choose PVsyst where a lender names it, and for high-latitude ground-mount where its geometry handling is well trusted.
• Choose HelioScope for commercial rooftop engineering where someone else builds the customer document.
• Avoid any tool that reports only an annual shading percentage. In Canada that number conceals the months that matter.

The Bottom Line

Canadian shading analysis is about December, and the annual average is the wrong unit of measurement.

• Report shading monthly, not annually. A 5% annual loss can be a 23% December loss, and the customer experiences the second one.
• Price the loss against the province. A shaded kWh is worth roughly three times more in Ontario than in Manitoba, and that decides whether mitigation pays.