Solar panel efficiency and what affects it
For your home to run an efficient solar solution or to be approved for Government incentives that the conversion attracts your home needs to pass several pre-requisites.
Tilting
The tilt or pitch of your solar panels has a direct impact on their efficiency, output, and of course, overall return on your investment.
To get the most out of your panels they need to be faced towards the sun, and in the southern hemisphere that is directly north. Some houses don’t have roofs that are true North but have variations that include North East and North West and these rooves can still be very effective, this is talked about in more detail in the orientation section next.
Unless you’re investing in a solar tracker your panels will be installed and then remain in a fixed position, and the angle with which your panels face the sun will have a direct impact on the volume of the energy they produce. The panels will be performing at their best when they are at a perfect right angle to the sun, but the sun is very rarely straight up, it rises in the east and sets in the west, so to get the best of the sunshine hours 10am-3pm the solar array needs to be pitched anywhere between 20°&40° with the optimum angle being around 32°.
If you home doesn’t have enough tilt Sun Connect can install sturdy brackets that can bring your solar panels to the optimum pitch, added to this Sun Connect’s accredited installers are very well trained, experienced, Clean Energy Council accredited and fully aware of the requirements to gain and maintain full solar panel efficiency.
Orientation
As stat
ed earlier, solar panels work most efficiently when they are facing true North, but it’s not all that common that houses actually face in true north position. But this isn’t generally an issue because solar panels are still above 85% effective at a north east or north west position, many smaller homes that have a higher electricity usage will find they need a system that is separated onto different rooves (which Sun Connect is happy to organise) in this case the majority of the panels will be installed on the most effective side of the roof and the remainder on the next most effective area.
Once installations start occurring on the true east or true west sides of your roof you’ll notice that efficiency can drop by as much as 40% and it’s generally not recommended that you do this, added to this the Government funding that solar panels attract is only really reserved for homes that have rooves that are correctly pitched and orientated.
Australia, being in the Southern Hemisphere, experiences a sun that is predominantly coming at us from the North. There is of course deviance throughout the seasons, but ideally solar panels should be facing as close to true North as possible to reduce the impact that the Winter seasons have on efficiency.
North Easterly and North Westerly facing panels will be largely operating at around the 90% of their rated outputs. However, once angles start approaching East North East or West North West orientation, the numbers start reducing rapidly. A directly East or West facing panel will never operate at better than 85% of its rated output.
Shading
Another variable that can affect solar panel output is shade. Shade from trees or shade from nearby structures or buildings, can significantly impact how much sunlight gets to your panels and in turn how much free, clean electricity is generated from your solar investment.
Shade has varying levels of impact and the lower the quality of your panels the greater that impact becomes, cheaper panels don’t generally have circuit breakers, meaning even if a small portion of shade is across one of your panels the entire solar panel system can stop working. But the better systems (including Sun Connects) have these circuit breakers meaning if a part of a panel is in shade only that part of the panel in ineffective.
There are things you can do to remove the shade, obviously if there is a building or other man made obstruction that over shadows your roof, other than going through your council or other legal channels you pretty much have to grin and bear it, but if it is a tree then you do have the option of pruning it or removing it completely, but again speak with your council before you proceed and if successful organise an arborist to get the job done properly.
Space
Each panel is approximately 1.6m high by 0.8m wide, so for a 1kw 6 panel system in a line, you will need 1.6m x 5m (7.5m2). Be aware that you may not be too close to valleys and at least 2 rows from the ridge cap.
Many homes also have split level roofing, with enough space for a large system, but not all on the one section of the roof. Sun Connect does have the option of splitting systems if conditions require.