Solar panels distances from things

arty688

Hello,

Just trying to work out how many panels I can squeeze onto my roof.

From googling it seems to be 30cm from the edges/ridge tile.

However I can't seem to find how far from a dormer or Velux (I have both).
Does anyone know how close you can put panels to these ?

Cheers 

matelodave

You should also take into account where the shadows form as there's no point in having a panel right next to a dormer if it's shaded during most of the day

arty688

Cheers,

I have taken that into account all panels will have to be optimised anyway as I also have a few surrounding tree and panels would be on south,east and west facing roofs .

Not an idea setup but you've got to work with what you have , I do use 20000kwh a year so should use most of what I generate with the help of a battery.

QrizB

arty688 said:

Just trying to work out how many panels I can squeeze onto my roof.
From googling it seems to be 30cm from the edges/ridge tile.

Minimum distances from edges are all to do with wind loads. If panels are too close the wind can get under them and pull them off the roof. (No smart comments from aerodynamicists, please.)

However I can't seem to find how far from a dormer or Velux (I have both).

Does anyone know how close you can put panels to these ?

I would expect you could go right up toeither, although as matelodave says beware of shading from dormers. Shading should be less of a problem from a Velux!

Benny2020

"I do use 20000kwh a year"

How?

arty688

No gas and plug in hybrid 

Martyn1981

QrizB said:

arty688 said:

Just trying to work out how many panels I can squeeze onto my roof.
From googling it seems to be 30cm from the edges/ridge tile.

Minimum distances from edges are all to do with wind loads. If panels are too close the wind can get under them and pull them off the roof. (No smart comments from aerodynamicists, please.)

However I can't seem to find how far from a dormer or Velux (I have both).

Does anyone know how close you can put panels to these ?

I would expect you could go right up toeither, although as matelodave says beware of shading from dormers. Shading should be less of a problem from a Velux!

I'd agree, and we actually have panels on 3 sides of a Velux on ESE roof. They go right up to it.

Do consider also that whilst the panels will most likely sit proud of the Velux, if you open it more than a couple of inches, then it may start to shade the panels a bit.

2nd_time_buyer

For the edges, it is worth looking at the manufacturers data for the mounting system you are using. Some say 0.2m from the edges and ridges. It is a bit vague on the gutter, but even so you don't want the water to overshoot. 

I was pretty tight on the margins for our roof. And allowed 0.2m at the top and sides and just less at the bottom. Effectively it meant I could get another 1.5kw of panels up

During the recent storms we lost a few ridge tiles off a bit of roof away from the panels. But no problems with the panels at all. 

arty688

Cheers going up to the Velux and potentially being able to go closer to the edge would make a big difference I think. Although its like a maths problem as you then have to look at what size panels suit your roof . It maybe worth going for lower powered smaller panels to actually get more in total. If aesthetics wasn't a consideration I could consider each space individually using micro inverters.

QrizB

arty688 said:

It maybe worth going for lower powered smaller panels to actually get more in total.

That's what solar tiles give you, but unless your roof needs re-tiling anyway the price premium tends to be prohibitive.

Martyn1981

arty688 said:

Cheers going up to the Velux and potentially being able to go closer to the edge would make a big difference I think. Although its like a maths problem as you then have to look at what size panels suit your roof . It maybe worth going for lower powered smaller panels to actually get more in total. If aesthetics wasn't a consideration I could consider each space individually using micro inverters.

Yep, same here. There was no good way to put 1m x 1.6m panels on our roof because of the Velux, but 1m x 1.3m panels fitted almost perfectly in a 3 rows and 5 columns layout, with the top row missing the second and third panels due to the Velux.

None of the installers came up with it, but a bit of Googling by me, and the problem was solved, well, that and a scale drawing of the roof and velux, and some cut out card PV panels to play with.