The direction you choose to face your solar panel is all important.
In fact, when it comes to the installation it’s the most critical factor.
The way you face a solar panel is known as ‘orientation’ and getting this wrong leads to a catastrophic loss in performance.
This is because you need to make sure your equipment is pointing towards the sun to benefit from its full effect.
In this article you learn what direction solar panels should face, tips to improve performance based on your energy use, and mistakes to avoid.
Please note, the information below is based on Northern hemisphere countries like the USA, Canada, UK, and Europe. For the Southern hemisphere, like Australia and NZ, the orientations are opposite.
Best Direction for Solar Panels to Face
The best way to face solar panels is in the South. This orientation offers the highest overall electricity production over the course of a whole day.
While the sun rises in the East and sets in the West, it moves through the Southern part of the sky. You will particularly notice this during winter months when it sits lower in the sky (closer to the horizon).
You can easily see this for yourself on a sunny day. Go outside your house and stand on the South facing side, it will be bathed in sun. Then go to the North side and it will be completely shaded with little direct sunlight.
Now if we apply that logic to solar panels which need direct sunlight to work efficiently.
Where would you choose to put them?
On the Southside of your property. Even placed high up on a rooftop the logic still applies, especially if you have a pitched roof.
Mounting solar panels to face South allows them to operate at near 100% efficiency, while other orientations can lead to 30% or more power loss.
How to Work Out Which Way is South
So how do you know which way is South? Well, it should be pretty easy to work out, here’s 3 ways:
Locate the Sun at Midday
Wait until midday and then check where the sun is in the sky. At this point in the day it will be in the middle of the sky but slightly closer to one horizon. This direction is South.
Use Google Maps
You can easily use Google maps which has an inbuilt compass. It appears just below the terrain toggle on the right side of the screen. To activate it, swipe up in the middle of the screen with two fingers. Then point your phone in the opposite direction to North.
Get a Compass
A compass is designed to do this exact job. It is used to orientate you anywhere on Earth. You can pick them up pretty cheap from Amazon or even download a dedicated app on your smartphone.
Pointing Solar Panel East or West
If you walk around your local neighborhood you might start to notice something odd… Not all solar panels are facing south, but why is this?
Well, there’s several reasons you might point to a solar panel East, West, or somewhere in between.
Lack of Space
Not everyone has enough South facing roof space to install the amount of solar panels they want so a compromise is made. You might see the complete solar array spread out over various orientations in this scenario. While it is not optimal for energy harvesting, you can still get decent performance from solar panels facing these directions. But you will certainly see a 15% to 20% performance drop on these orientations.
Time of Use Rates
Many energy suppliers now use different tariffs for energy usage throughout the day. These peak and off-peak prices are based on demand, a bit like train tickets which are more expensive during commuting hours. Generally, this makes energy more expensive in the evenings when most people are at home watching TV, cooking, using lights etc.
Often people look to offset this Time of Use rate with solar panels. Of course, during late afternoon and evening, the sun is in the Western half of the sky. So at this time, a West facing solar panel will perform the best.
It means your solar electricity production will be higher in the evening but reduced across the course of a whole day.
Avoid North Facing Solar Panels
It is good practice to avoid installing North facing solar panels. You will lose a lot of efficiency with this orientation. This is because the solar cells will get very little direct sunlight, especially outside of peak summer. As you can see on the image above, the performance loss could be 30% or more!
Roof Pitch and Tilt Angle is Important
Most houses have pitched roofs which makes them perfect for solar panels. This is because you should mount them at an angle to point at the sun. The best tilt angle for solar panels is between 30 degrees and 45 degrees. And most rooftops are within this angle so you can mount solar panels parallel to the roof.
When it comes to flat roofs you should add tilt angle mounts to solar panels to produce the best performance. You will see this in action on flat roofs like this:
Do Solar Panels Laid Flat Still Work?
Despite the benefits of tilting a solar panel to face south, many people still mount them in a flat position. This means they face straight up into the sky. The reasons for this vary from aesthetics to vehicle performance.
The most common place to see flat solar panels is on RVs and campervans. On these vehicles, it is more practical to lay solar panels flat. This is to avoid drag when driving and avoid excessively tall vehicles.
Of course, solar panels still work well when laid flat, especially during the summer. Although many owners report severe reductions of 50% or more during winter months.
Overall through the course of a year, you can expect a 10% performance loss from flat solar panels.
What Direction Should Solar Panels Face Summary
Well, the best direction for solar panels to face is South towards the equator.
There’s no arguing about the fact that this orientation will deliver higher overall electricity production.
In some circumstances it is not possible to get everything pointing in this direction, so you can compromise with Easterly or Westerly directions. While you should avoid North facing as much as possible.
