Solar panel orientation and location are two of the most fundamental factors that determine the efficiency of a solar power system. The direction your roof faces and the available area on your roof are two major aspects to consider when deciding to go green with solar.
The larger the surface area of a solar panel is exposed to the sun, the more energy can be harvested through the solar power system. Correct orientation and positioning of the solar panels assures that your solar panels get access to the sun throughout the day. Solar panels have to face the Sun at all times of the year in order to maximize the energy yield. Solar installers achieve this by facing the panels towards the South in the northern hemisphere and towards the north in the Southern hemisphere. This is generally referred to as the ‘tilt’ of the solar system.
For most Australians, the least preferred direction is to have the panels facing south. Professionals would consider installing panels facing south almost as large a mistake as installing them upside down. In Sydney, south-facing solar panels will produce around 28% less energy than north-facing panels. In some rare cases, when the only available space for a roof is facing south, the installers can use “Tilt frames” to install the panels such a way that with the use of these tilts, the sunlight they receive is similar to what they would get if they were placed on a north facing roof. These tilt frames however cannot be installed on tiled roofs but can be useful for people with tin roofs.
Ideal Solar panel Orientation in Australia
North facing panels are considered the most suitable for people who are likely at home during the day as this panel orientation produces the most electricity overall than having the panels in any other direction. The North facing roof captures the most sun across Australia, thus giving the homeowner the most solar energy over any 12 month period.
This is one of the reasons why most solar installers highly recommend having panels on the north facing roof but in the recent past more and more people have begun favouring the east and west directions for installing their solar panels. Having the panels on the east and west direction has made the electricity usage of the Australian population more in sync with the usage of a vast Australian population. Most “office and school goers” are likely to be available at home to use the solar power during the early mornings and during the late afternoon which works perfectly with the timings solar power generation is at its highest with the east and west orientation. Solar panels installed on west facing roofs produce around 12% less electricity overall than the north-facing panels. They also produce less electricity in the morning compared to the afternoon. Having the panels installed on the west facing roof can be ideal for people with high demand for air conditioning in summer as panels placed with this orientation reach their maximum output during mid-day – when it tends to be the hottest. It’s also an excellent direction for people who are usually out of the house by the time the sun comes up but return in the afternoon.
Seasonal Tracking for Solar
The Sun follows a different path through the sky during winter than in summer as we move away from the equator. So, in order to capture as much energy as possible from the Sun throughout the year, it is recommended that solar panels be tilted at a certain angle (depending on the latitude) 3 or 4 times a year. This is called seasonal tracking. For small residential systems, seasonal tracking is often done manually but for large arrays in utility scale plants, this is achieved by a mechanical device (gears, actuators etc.). The gain from having a solar tracker is dependant largely upon the latitude and upon the climate at that location. The maximum gain that you may expect is in summer and at the greatest latitude. You would get more than 100% gain from a tracker on the north or South Pole in mid-summer as opposed to a fixed solar array at that location. In mainland Australia the greatest gain would be in Tasmania.
Solar modules still work under partial shading or cloud cover, but at a reduced rate because the panels are operating mostly from diffused sunlight instead of direct sunlight. When it is heavily overcast, the solar module ceases to function completely, but that occurs surprisingly rarely. The reverse happens with gain from a solar tracker in winter when you may expect no power generation at all on the north and South Pole and the gain is significantly reduced at other latitudes.
In conclusion, based on Australia’s location in the southern hemisphere and the positioning of the sun, the north facing roof is considered the most ideal, next preferred directions are the west and east facing roofs depending on what hours of the day you are most likely to have higher usage and the south pitched roof is the least preferred and if it is insisted upon due to no other available option, it is best to have these panels installed with tilt frames.
Contact Solar Power Nation today for expert advice and recommendation for the best solar panel layout configuration specific to your roof!