Optimum pitch for PV on a new build

[Doing it for the kids]

just getting drawings and final plans for decent sized building SSW facing drawn up.

Current pitch is likely to be 12 degrees, increased from 9. How does that work for any array?

Footprint is 90x30m, what sized array could I fit on the roof and what possible cost?

TYIA

@akaPABLO01
@f0ster

 

[matthew]

Have you checked with the local power network, to see if there’s room on the grid for your output? Or are you planning to use it all on site?
Ours is on two buildings 75 x 25 (2) with the pitch 30 degrees. 50kw

 

[Doing it for the kids]

Have you checked with the local power network, to see if there’s room on the grid for your output? Or are you planning to use it all on site?
Ours is on two buildings 75 x 25 (2) with the pitch 30 degrees. 50kw

thanks

I have already but will again once we gear up for the build itself. For now I just want to get planning, the PV will help

so you have 2 number sheds of 75 x 25 metres each, so roughly 937 m2 per half of each roof giving you about 1875m2 assuming you only use half of each roof and not allowing for the extra surface area on the sloping roof?!

if so I will only have 1350m2 on the same basis so just under 3/4 of the space so 35 kw or so?

 

[f0ster]

with a foot print of 90X30 assuming the south side of the roof is about half this size (90x15) it will hold about 185kw using a 250w panel. that is with the panels mounted landscape. the optimum pitch is about 35/36 deg.

 

[matthew]

thanks

I have already but will again once we gear up for the build itself. For now I just want to get planning, the PV will help

so you have 2 number sheds of 75 x 25 metres each, so roughly 937 m2 per half of each roof giving you about 1875m2 assuming you only use half of each roof and not allowing for the extra surface area on the sloping roof?!

if so I will only have 1350m2 on the same basis so just under 3/4 of the space so 35 kw or so?

 

[matthew]

^^^

There is more room on these two roofs, but no more room on the grid plus no PP needed at under 50kw.

The taller silage barn is a slightly steeper angle than the 30 degree lean to below it.

 

[Exfarmer]

To answer your question. Believe you are in Warrington so the answer is the ideal is 53 degrees.
Going sharper will give better out put in the winter, less better in the summer..
In fact within 15 degrees either way will make little difference

 

[snarling bee]

Are you getting your shed sizes mixed up with metres and feet. And foot print is twice the south facing roof size if you have it symmetrical.

My 120x70 feet grainstore has 38.4 kw on the roof (one side) you would get more now as panels are better.

 

[Doing it for the kids]

Are you getting your shed sizes mixed up with metres and feet. And foot print is twice the south facing roof size if you have it symmetrical.

My 120x70 feet grainstore has 38.4 kw on the roof (one side) you would get more now as panels are better.

Not sure who you aimed that at? I’m talking in metres, easy to get confused especially as a 90m shed isn’t the norm

 

[matthew]

Are you getting your shed sizes mixed up with metres and feet. And foot print is twice the south facing roof size if you have it symmetrical.

My 120x70 feet grainstore has 38.4 kw on the roof (one side) you would get more now as panels are better.

I didn't specify. But our roofs are measured in feet, not metres.

 

[akaPABLO01]

The only issue with low pitching roofs is the panels collect a lot of grime on their lowest point.
You’ll probably seat 1,120 panels at 330W
Giving 369.6kWp

That’s 28(down)x40(across) landscape.

 

[snarling bee]

[90m shed isn’t the norm [/QUOTE]

Only 90m. If you want to willy wave I have one that is 108m, or 360ft in old money, built in the 60s

 

[Doing it for the kids]

[90m shed isn’t the norm

Only 90m. If you want to willy wave I have one that is 108m, or 360ft in old money, built in the 60s[/QUOTE]



It’s not about the size but what you do with it that counts