If you’re thinking about installing solar panels in Ottawa, one of the first questions you’re probably asking is:
“What size solar system do I actually need for my home?”
Getting the right solar system size is critical — it affects how much you save, how much you can offset your hydro bill, and how quickly your system pays for itself.
In this guide, we’ll walk you through how solar system sizing works in Ottawa, give you real-world examples, and show you how to choose the perfect setup for your home and lifestyle.
How Solar System Sizing Works in Ottawa
When sizing a solar system, there are a few important factors to consider:
- Your average electricity usage (measured in kWh per year).
- The available roof space and roof direction (south-facing is ideal).
- Local weather patterns (Ottawa gets a solid amount of sun — about 1,200–1,300 kWh/kW per year).
- Your energy goals (do you want to offset 50%, 75%, or 100% of your usage?).
In Ottawa, a general rule of thumb is:
1 kW of solar panels produces about 1,200–1,300 kWh per year.
If your home uses 10,000 kWh per year, you’ll likely need an 8 kW system (because 8 × 1,250 = ~10,000).
Real-World Examples: Solar System Sizes for Ottawa Homes
Here are some real examples based on typical Ottawa homes:
| Home Size | Annual Electricity Usage (kWh) | Recommended Solar Size | Panels Needed (roughly) |
|---|---|---|---|
| 1,500 sq. ft bungalow | 7,000 kWh | 5.5 kW system | 13–16 panels |
| 2,000 sq. ft detached | 10,000 kWh | 8 kW system | 18–22 panels |
| 2,500 sq. ft detached (electric heating) | 14,000 kWh | 11 kW system | 24–28 panels |
| 3,000+ sq. ft executive home | 18,000+ kWh | 14–16 kW system | 30–36 panels |
Notes:
- Homes with electric heating, hot tubs, pools, or EV chargers will need larger systems.
- Battery storage can be added later to maximize self-consumption and save even more.
How Roof Size and Shape Affect Solar System Sizing
Even if you want a 10 kW system, your roof layout can limit your installation.
In Ottawa, the average solar panel is about 18–21 square feet and produces 400–450 Watts.
Example:
- A 10 kW system typically needs about 500–600 square feet of clear roof space.
- South-facing roofs are ideal, but east/west roofs can still work with some output loss (about 15% less).
If you have a complicated roof (lots of dormers, vents, or shading), a solar installer will design a system with optimized panel placement or microinverters to get maximum production.
How to Estimate Your Home’s Solar Needs (Quick Math)
Here’s a simple method to ballpark your system size:
- Find your annual hydro usage — look at your Hydro Ottawa bill (it’s listed in kWh per year).
- Divide your usage by 1,250 (average production per kW in Ottawa).
- Result = Size of system needed in kW.
Example:
- You use 9,600 kWh/year.
- 9,600 ÷ 1,250 = 7.68 kW system needed.
A professional solar assessment will fine-tune this based on your roof size, orientation, and your personal energy goals.
Why System Size Matters for Rebates and Loans
Right now in Ottawa, homeowners can access incentives like:
- Canada Greener Homes Loan: up to $40,000 interest-free for solar installations.
- Home Renovation Savings Program: up to $5,000 rebates for solar systems.
- Net Metering: earn credits on your hydro bill for excess solar you export.
Choosing the right-sized system ensures you maximize your rebates, optimize your loan amount, and get the best return on investment.
Ready to Find the Perfect Solar System Size for Your Ottawa Home?
At True Beacon, we specialize in custom-designed solar systems built specifically for Ottawa homes.
We’ll assess your roof, analyze your energy needs, and design a system that maximizes your hydro bill savings and qualifies for the best rebates available.
Contact us today for a free, no-pressure consultation — and let’s find out what size solar system is perfect for your Ottawa home!