Solar Panel Estimator
Estimate how many panels fit on your roof, the system size in kilowatts, and roughly how much electricity it could produce each year in your province.
Your results
Worked example
A home in Ontario with 40 m² of usable roof:
- Panels: 40 ÷ 1.7 m² per panel = 23.5, so 23 panels fit
- System size: 23 × 400 W = 9.2 kW
- Yearly production: 9.2 kW × 1,100 average peak sun hours = 10,120 kWh per year
The average Canadian home uses roughly 10,000 kWh a year, so a system this size is in the range of covering a typical household's usage on an annual basis.
How this calculator works
Panel size of 1.7 m² and 400 W per panel are typical current residential figures, stated here so you can compare quotes on the same basis. The sun-hours figures in the province list are rough averages of yearly peak sun hours; a site assessment with your exact roof angle, direction, and shading will differ, sometimes by 20 percent or more.
Common questions
Does roof direction matter?
Yes. South-facing is best in Canada. East or west-facing roofs typically produce 15 to 20 percent less, and flat or north-facing sections are usually poor candidates. Snow cover also trims winter production, which is already the low season.
What does a system like this cost?
Installed residential solar in Canada commonly runs about $2.50 to $3.50 per watt before incentives, so a 9.2 kW system is a significant project. Get at least three itemized quotes, and check current federal and provincial incentive programs, which change often.
Estimates only. Results are provided for planning purposes and are based on the figures and assumptions shown on this page. Sun hours are rough averages, labelled as such, and actual production depends on roof angle, direction, shading, snow, and equipment. This is not an engineering assessment. Mississippi Maple accepts no liability for purchase decisions made using this calculator.