Quote Advice

[Somecamel]

Yer, I'd go with him

 

[FB.]

Got some more info on shading issue (Quote 4).
A 16 panel install (landscape) would have 6.1% and 9.4% shading on panel row 1&2 receptively on column 1 at west cable and 3.9% and 5.4% on column 2. Shading at east gable would be 2.6% and 4.7% column 7 and 2.8% and 5.7% column 8.
Proposed 12 panel solution has 3.7% & 4.9% column 1 and 2.7% & 4.9% column 8 with rest on panels ranging from 2.7% to 3.7% on rest of panels.

Would it be better to go with 12 panel solution with reduced and better shading spread or 16 panel solution more compromised on shading but with better inverter that could handle shading issues?

It sounds as if the shading issues are complex - affecting both ends of the array and at different times of the day as the shadow moves around.
If shading is not a problem from 9am-3pm in March-October then the shading might not be worth worrying about. If shading is between peak hours (9am-3pm) then you could have all sorts of gremlins to deal with.

Can you take a screenshot of your house roof from Google Maps and post it up, so it is easier to visualise?
Link to Google maps here:
Google Maps

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[pat72]

It sounds as if the shading issues are complex - affecting both ends of the array and at different times of the day as the shadow moves around.
If shading is not a problem from 9am-3pm in March-October then the shading might not be worth worrying about. If shading is between peak hours (9am-3pm) then you could have all sorts of gremlins to deal with.

Can you take a screenshot of your house roof from Google Maps and post it up, so it is easier to visualise?
Link to Google maps here:
Google Maps

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Thanks for the info' Overhead of bungalow roof attached
Cheers.

 

[FB.]

I'm struggling to see where any significant shading will come from, unless there is something tall off the bottom edge of the picture, or a TV aerial which isn't showing in the picture. The Google picture will have been taken in summer, and you can see the whole roof is in full sun.

From what I can see, your proposed panels should be free from shading at their peak generation times (9am-1pm for SE and 11am-3pm for SW) during spring, summer, autumn.
Generation early or late in the day is much less due to low-in-the-sky weak sun. The same is true of winter. Most arrays have minor shading early or late in the day - even if it's a terrace of houses across the street!

As for how attractive rectangular panels will look on a triangle/pyramid-shaped roof is a different matter.

 

[FB.]

You may be able to use the following sun chart to visualise which arc, and how high the sun will be at various times of day and various times of the year:

Sun Position Calculator | PVEducation

My position, in Cambridgeshire, is approx latitude 52 and longitude 0, GMT offset 0 until British Summer time kicks in.
Bolton (you mentioned living in the NorthWest) is approx latitude 54, longitude -2.

 

[Dave-geo]

FB

Have checked on Street View and the building that is a bungalow is the top building in the picture not the one with triangle shaped roofs. Looks great for PV to me.

Edited to add that you might want to ask next door if you can lop their conifer a bit :smiley2:

 

[whinmoor]

Yes - looks very good for solar panels. Lots of roofspace to play with.

 

[Ian-LS]

Nope i can't see any major shading issues with that roof.

 

[pat72]

Following up on shading. Conifer at east gable is high as roof ridge. Saw a bit of shadow on roof from it at 8am on sunny day last week with sun peeking over corner of neighbours roof. Another tree just past west gable on neighbours side is approx 15 ft above roof ridge. There also a small chimney near west gable end and a flue in the middle. Surveyor demonstrated PVSOL software showing shading across different panel string configurations.
So is shading enough of an issue to warrant reduced array size and/or better inverter?

 

[Earthstore]

That fir tree could grow 18" a year, so may become more of a problem, however the sun is higher in the sky in the summer so may not be a problem at peak producing times, you need to remember that it is not a power station on the roof, just a small system tickling away earning/saving you money, so every little helps.
The only way really to tell is to see it.

 

[FB.]

FB

Have checked on Street View and the building that is a bungalow is the top building in the picture not the one with triangle shaped roofs. Looks great for PV to me.

Edited to add that you might want to ask next door if you can lop their conifer a bit :smiley2:

But the opening post mentioned SE/SW roof. The upper bungalow has a SE/NW roof, while the lower bungalow has SE/SW (also less-useful NE/NW). I just assumed the lower bungalow was the one, as it has SE/SW options for mounting panels.

 

[Dave-geo]

FB. You are right it is confusing but if you look on Street View the lower bungalow is a house :smiley2:

 

[solarnorth]

Hi

Shading is a major issue - Just completed install in Manchester last month with shading issues from 2 trees. Installed Solar Edge - good kit and it does what it says on the tin - output figures are slightly below other 4KWp systems last month so generally happy as is the customer - The additional cost is relitively small for what you get so worth consideration