How do you know if solar is worth it for your home? The best way to evaluate the financial implications of solar is to compare your solar costs and production to your annual usage and power bills. If you're shopping for quotes, you’ve probably seen a lot of different numbers and terms being thrown around. Let’s break down what all of that means, so you have a better understanding of how solar production works.

How Many Solar Panels Do I Need to Offset my Usage?

We get a lot of questions about solar production and the ideal system size. The truth is every home is different, and there isn’t a one size fits all system. When we design your solar system, we base the size on your consumption. The number of panels you’ll need varies depending on the solar panel’s power rating and efficiency, with the average solar panel having a power rating between 250 to 400 watts.

This is important because your total output will differ greatly depending on the panel type you use. 20 panels rated at 250 Watts will get you a 5kW system, while 20 panels rated at 400 Watts will get you an 8kW system.

At Polaron, we use highly rated 455W monocrystalline panels that are perfect for Canadian weather. With higher-rated panels, you’ll need less to offset your household’s usage completely. 

While your panel’s power rating indicates the maximum amount of watts it can generate, your panel’s efficiency lets you know what percentage of the sun’s energy can be converted into power for your home.

How do you calculate your panel’s production in kWh

To calculate your solar system’s production, you’ll need to know your system size and peak sunlight hours in your area. Please see the chart below to find the average peak sunlight hours in your province.

Referenced from: 

We’re going to show an example using our 455W panels and an average 3.5 peak sunlight hours. Let’s crunch up some numbers!

If you’re using a panel with a power rating of 455 watts and receiving 3.5 peak sunlight hours, that panel is producing about 1.6 kWh of electricity a day. Now multiply that number by 30 days to get 48 kWh of average solar production from a single panel per month.

Now onto your usage! The average annual household usage in Canada is around 11,000kWh, which means an average of 900kWh per month. Divide your monthly usage (900kWh) by the monthly production of a single solar panel (48kWh) to get the number of total panels. In this case, we’ll need about 19 panels to completely offset your usage.

To calculate your total system size, we just have to multiply the number of panels by your panel’s power rating. 19 panels multiplied by 455 watts gets us an 8.6kW system.

If you’d like to see how much your solar system might cost, check out our blog that breaks it down province by province.

Please keep in mind that these are very rough estimates. For a more accurate look at your potential production, we recommend getting a couple of solar quotes from reputable companies.

Do I Need a Battery to Store My Extra Power?

Sometimes you don’t use all the energy your panels produce right away. Batteries are commonly used to store excess electricity for homeowners to use during the night and on cloudier days. Another popular option many solar customers are taking advantage of is Net Metering. 

Your utility company offers net metering programs as a more affordable storage option. You still get to use all the energy produced by your system first, but the excess can now be sent to the grid—and in return, you’ll receive credits. These credits are usually worth the same rate that you pay and will be deducted from future power bills. We recommend contacting your utility company to get more familiar with their specific Net Metering policies.

What Affects Solar Production?

Two households with the same size systems can have different production outputs. Most solar installers will offer you a production estimate with your quote, which is meant to give you an idea of how much power your system is expected to produce every year.

Location: Places with higher peak sunlight hours will have more overall production.

Weather: You should expect to have lower production during the winter compared to the warmer summer months.

Shade: Any obstructions that block sunlight from reaching your panels will lower your production.

Although we account for these factors in our estimate, you should still expect some minor normal variances from year to year.

How Do I Know If My System is Worth It?

These numbers aren’t really helpful without applying them to your potential savings. If you want to see how much you can actually save with solar, we can get you started with a free quote that lets you know your estimated production output and projected savings. Even better, we have a financing program that can go as low as 0%, so you can easily compare your monthly solar costs with your power bill and projected savings.

The best way to figure out your production is to let a professional help you out. Fill out our quick and easy survey to start your solar journey today. 


 Average Peak Sun Hours (Canada) - Climatebiz

How Much Energy Does A Solar Panel Produce? – Forbes Home

Residential Electricity and Natural Gas Plans & Options (