Solar panel orientation

Which is the best direction to point your solar panels?

It’s an interesting question and you would think the answer is pretty simple – NORTH.

In many cases you’d be right, a north facing solar array will generate more electricity than an array that faces east, west or south. In Geelong, putting panels on an east or west roof will normally result in a loss of around 15%, compared with a north facing array on a 30 degree pitch. Many people are surprised by how small this loss is and it certainly doesn’t rule out these options. It’s  recommended however to steer away from south facing panels where possible, where losses are in the range of 30-40% on a standard home’s roof pitch.

Solar panel oreintation

With the introduction of lower feed in tariff (FIT) rates for your solar electricity that’s exported to the grid, an interesting discussion about solar panel orientation has come about. Should we be facing our panels west?

Sure a north facing array generates more electricity than one that faces west, but it generates the peak of it’s generation for the home in the middle of the day. For the average working family that has a low electricity consumption during the day it could mean that a lot of the electricity generated is being exported to the grid at the current FIT rate of 8c/kWh. The theory is, that if you were to face your panels west, they would generate more electricity later in the day, when you are more likely to be using the power. In this case you would be able to offset the cost of buying electricity from the grid at the going rate (often over 30c/kWh), which is more valuable to you. This is true particularly in summer when solar production is higher and the daylight hours are longer extending into dinner times.

Another related argument for pointing panels west comes from a Renew Economy article where Adam McHugh, a lecturer in energy economics and energy policy at Murdoch University, where he suggests that pointing solar panels west, would correlate the systems output with times of peak demand on summer afternoons. On hot sunny days when everyone turns their air conditioners on, west facing solar panels would be producing electricity. West facing solar has the potential to compete with the distribution network and expensive peak generators by reducing the cost of supplying electricity particularly during peak demand events.

The orientation of your roof and available space may be the deciding factor in the end, but it’s good to know that there are normally a couple of options. A good solar installer will give you a comprehensive analysis of your solar systems production as part of your quote. This should show average daily kWh estimates broken down monthly and for the year based on your roofs orientation and pitch.

For more info on panel orientation or the potential of you roof give Green Energy Options a call on 1300 931 929.