The direction solar panels face for optimum sun exposure varies depending on location. In Australia, solar panel yields are higher when solar panels are facing north. In fact, all Southern Hemisphere locations should ideally position panels in a northerly direction.
The direction solar panels face, along with their angle, or tilt, at that orientation; are all vital inputs in order to accurately calculate the solar power for the property. These inputs, along with the location of the property, are needed to calculate the solar energy at a given site.
For Australian conditions, the best orientation for your panels is NORTH. Although, if your panels do not face north you can still generate good solar yields.
What if your panels aren’t facing north?
If you live in Perth, and your panels don’t face north, your property may still be suitable for generating solar energy. If your property faces east or west, panels can still generate good yields. Depending on your roof pitch and location, you will lose somewhere between 10-20% efficiency as a result of not having panels facing north. If you have the option to place the panels in more of a north-east or even north-west direction, it is recommended. This will increase sun exposure to the panels and therefore increase the systems ability to generate solar power.
If your property is constructed in a way that you are only able to face solar panels in a southernly direction, then you will also lose further capacity, in comparison to a north facing solar system.
The below table shows the efficiency of panels in Perth at different orientations, this is based on a roof pitch of 25°.
When you cannot orientate panels in a northerly direction in Perth, a greater emphasis is places on the angle of the panels. In this situation, a rooftop closer to horizontal will generate better solar yields. The smaller the roof pitch is, the better for south, east or west facing buildings.
Is East or West Better for my Panels?
When you consume most of your electricity, the affect of shading and whether or not your current system has solar battery storage are important considerations. Especially when deciding whether or not you should face your panels east or west.
Your electricity consumption habits and orientation
Figuring out when your building consumes most of its electricity is important when determining the orientation of your panels. If your household or even business uses most of its electricity during the late afternoon, then you are better off facing your panels west rather than east. The financial benefit of this, is that it coincides with the time of day that your electricity retailer will charge you peak rates when purchasing your power from them. Due to this, some cases where a lower yielding west-facing panel is favoured over a north-facing panel. However, careful design and modelling should be carried out before opting for west over north with your retailer.
On the contrary, if your electricity consumption is greater during morning daylight hours, then you may want to consider positioning the panels facing east rather than west. Additionally, the renewable energy you produce will save you from peak morning electricity rates.
Shading may be an issue to the east or west side of your property. if it is, and it blocks the daylight sun to your panels it will result in a loss of solar energy production. If only one side, east or west is exposed to shading then you should consider placing the panels on the opposite side.
How will battery storage affect orientation
If your solar system has a battery that is able to store excess solar energy then you are somewhat insured against peak morning and afternoon energy rates. You should always position your panels in a direction that will maximise daily solar exposure.
At Westsun Solar we have a team of trained professionals that can help you design and install your system. If you have any questions regarding the orientation of your system do not hesitate to contact us!