Variable angle for PV

[CotswoldDoItUpper]

Does anyone change the angle of their PV between summer and winter? Just jacking up the back of a ground/flat roof mounted system in the winter and lowering it in summer to try and optimise gain? Up once and down once in a 12-month period, nothing more complicated then that! 
 

Just thinking through the design for my flat garage roof mounting and wondering if it’s worth it.  

[JohnMo]

Go on one the PV calculation websites, alter the angle and look at yield at different time of year.  Will make a difference, how many percent - nor sure

[ToughButterCup]

I doubt it ... but I can see @Onoff designing the automatic turnbuckle to jack it up and down, and the app that helps the owner decide when to raise or lower it

Then when he's done that, the tracking for orientating  the whole array  will be a breeze ..... what could go wrong?

[Marvin]

Its a right hassle. unless you have a sun guided system.

If the wind gets behind the panels they can be damaged.

I know that panels set up here at 18 degrees off vertical will produce the most PV over December and January.

 

Expected typical result on my 5.12kW PV : 152kWh in December and 162kWh in January on 23 degree roof.

Expected typical result on my 5.12kW PV : 222kWh in December and 222kWh in January at 78 degrees.

So a 46% increase over the winter, and of course a decrease if left over the summer.

That would equate to about 2 kWh extra a day.

 

https://re.jrc.ec.europa.eu/pvg_tools/en/tools.html

 

If you want to use the above tool, first zoom in on your home on the map. Yes your building.

[CotswoldDoItUpper]

So basically if I go for a 4kWh array and a 3.6kWh inverter the output will always be limited to 3.6kWh (I assume) therefore angling the panels to a maximum benefit reduces my output in summer months anyway to 3.6kWh which means the inverter isn’t clipping as much over production off in the summer and I’m still getting the 3.6kWh but my winter production has increased by a significant margin. The angle is somewhere around 70%, similar to @Marvin’s 18deg off the vertical. 
 

think I might turn them into some sort of brise soleil for the garage! 
 

am I missing something? Most solar farms I’ve seen appear to be set around 45deg.

[Marvin]

11 minutes ago, CotswoldDoItUpper said:

 

am I missing something? Most solar farms I’ve seen appear to be set around 45deg.

Well 35 degrees ish. However it depends if you want the money or winter power as they are usually fixed position.

[Marvin]

12 minutes ago, CotswoldDoItUpper said:

So basically if I go for a 4kWh array and a 3.6kWh inverter the output will always be limited to 3.6kWh (I assume)

Er. not sure. Wont 4kW burn out the 3.6 inverter? I have 5.12kW and a 6kW inverter

[CotswoldDoItUpper]

14 minutes ago, Marvin said:

Er. not sure. Wont 4kW burn out the 3.6 inverter? I have 5.12kW and a 6kW inverter

The guy quoting said that it would be ok. I can’t have any larger without paying a small fortune to the DNO to upgrade the whole system, despite my neighbours having a perfectly acceptable 7kWh array!

[Marvin]

15 minutes ago, CotswoldDoItUpper said:

The guy quoting said that it would be ok. I can’t have any larger without paying a small fortune to the DNO to upgrade the whole system, despite my neighbours having a perfectly acceptable 7kWh array!

Sounds like they got in first and took up all the spare capacity. This will be a lesson for people going forward.....

[billt]

2 hours ago, Marvin said:

Er. not sure. Wont 4kW burn out the 3.6 inverter? I have 5.12kW and a 6kW inverter

 

No. Inverters can cope with much higher nominal DC input power than their rating. They just reduce the power taken from the panels t match the output rating of the inverter.

 

For instance, I have a 5kW inverter, but it has 6kW of panels connected to it.