Are you considering switching to solar power for your home? One of the important things you will need to figure out first is which direction should your solar panels face on the roof.
In order for your brand-new solar panels to generate maximum power, you need to determine the best direction for them.
Generally, the professional who comes to install your solar panels will help you pick the perfect direction. However, if you live in the US, you need to follow the rule of thumb – your solar panels should be facing the true south direction.
Why? It’s quite simple: the more sunlight reaches your panels, the more electricity you will produce. That means lower electricity bills.
Regular South vs. True South
Regular south or also known as “magnetic” south is what the compass shows you. That’s right; a compass doesn’t show the true south.
A compass shows the south pole of the geomagnetic field of the earth. The general direction is right but not completely precise. The iron and nickel present in the earth’s outer core pull the compass needle a little away from “true” south.
The solar installer professional will calculate the magnetic declination of your location to rectify the compass reading. Another way to determine true south is to look at the shadows in noontime – a time when shadows from vertical objects fall from north to south.
Or you can simply look at the Google Earth’s view of your house; if you center the focus on your house and select “Grid” in the View menu, you can see the north-south gridlines provided by Google.
What to do if the Roof doesn’t face South?
In case your roof faces east-west direction, you can compensate by increasing the solar collector by using larger collectors or more solar panels.
You can also choose to mount the panels someplace other than your roof such as a wall that faces south or even your yard. Just remember, if you decide to go with the yard, always mount the panels on the ground. It’s not only cost-effective but it gives you easy access when you need to clean the panels.
How to Choose the Right Tilt for Your Solar Panels?
Your solar installer will also help you select the best tilt by calculating the angle based on your latitude. If you live in the US, multiply your latitude by 0.76 and then add 3.1 degrees. For more specific information about the ideal tilt of panels, you should consult with the installer.
Even though most people choose a fixed position, you can adjust the panel angle depending on the seasons to ensure you are getting maximum power. Generally, as you approach the equator, your solar panels should start facing straight, and as you approach the poles, the panels should be aimed lower in the sky.
One Exception to the Rule
If you live in an area with expensive time-of-use electricity rates, you’d probably want to break the “true south” rule.
In many places, people consume more electricity in the evening as they come home from school and work, and turn on different appliances like TVs, air conditioners, microwaves, etc.
Some utility companies try their best to avoid the surge in electricity usage which usually occurs during evenings by raising the electricity cost during these periods.
That’s where you, as a solar owner, can save some previous bucks. By installing solar panels on your roof, you consume less electricity from the grid which means you consume less electricity during peak hours.
However, if your panels are facing south, they won’t produce as many kilowatt-hours as they could if you pointed them to take advantage of the afternoon sun.