oz911
Member
Hi there,
I am looking at installing an east-west solar system and wanted to get an understanding of the optimum angle it needs to be installed on a flat deck roof (Melbourne)?
From my investigations it looks like 15 degrees is the best angle? Also does anyone have any links to various mounting systems out there that cater for east west installations? I like to be informed when talking to installers.
Thanks
Oz
That's a real interesting situation which will depend on what you are trying to achieve.
I blogged about solar angles at this link for overall efficiency (http://anewhouse.com.au/2015/08/solar-panel-alignment/)
However with panels facing directly east and west you will get a better spread of power across the day in the summer but not much power at all in winter.
Your orientation has been discussed in detail at the energy matters forum at this link: https://forums.energymatters.com.au/solar-wind-gear/topic5064.html?hilit=virtual%20tracking
I think if I had a flat roof I would be looking more at having one set of panels facing North East and the other panels facing North West.
oz911
Member
Hey Bashworth,
Thanks for the links and your input. I havent been quite complete in my information. The east - west array is to complement a 9.8kw North facing array. I am looking to install 4.3kw East and 6.2kw West. The array will be configured back to back /\/\/ formation.
I had found 1 mounting system but have misplaced the link to the supplier so I was hoping someone could point me to an E-W mounting system :). Also without a decent understanding of the shadows the panels will cast needed to understand the panel inclination. Everything I have read points to 10-15 degrees with anything higher or lower impacts the output. I also understand the impact of E-W mounting and the lower generation, the intention here is to increase the morning and afternoon production vs the solo N array.
Hope this gives more insight into the configuration.
Once again thanks for the input. I also played around with the pvwatts site you had linked and confirmed my 10-15 degree readings.
I would still say that you issue is a little more tricky than just looking at overall panel efficiency.
If you are looking to save on installation costs west and east facing will be cheaper.
If you want to maximise production at the start and end of the day I would think that a roughly north east and north west orientation would be better.
By roughly I would say you want to aim for the points where the sun rises, and sets at the equinox.
I would also suggest that an angle of 45 degrees would produce better early/late power than 15 degrees.
