Solar panels distances from things

arty688

Not sure small panels exist now though. I think 1.6m by 1 m is the new small.

Spies

Perlight 295w are 1504x1002mm if that's any help. 

1961Nick

Less panels means less optimisers which may be a consideration?

2nd_time_buyer

Another area that is inconsistant is the spacing between the panels. For panels on the same mounting rails they are automatically spaced 20mm by the attaching fixings. However between rows the spacing needs to be set.

Panel manufacturers all seem to recommend a (20mm) spacing between panels on all sides. However, this is not always put in practice.

This is normally claimed to allow thermal expansion of the panels. However, thinking about that, there is not just thermal expansion of the panel but also of the timbers in the roof, which I think might be more significant.

Another factor is if there is wind loading and the roof flexes at all, butted joints of the panels could put significant stresses on the panel edges.

Finally, if you have the panels close right up against each other, the rain water will flow over all the panels into (or over) the gutter. If you are concerned that the water may overshoot then a gap between panels will help divert some of the water on to the roof.

Small points but something I think it's definitely worth paying attention to.

arty688

Spies said:

Perlight 295w are 1504x1002mm if that's any help. 

Cheers,

For example I have a space thats 1.6m x 2.1m (300mm taken off edges) so I could fit 2 x 295w or 1 x 400w panel.

Although it would be maybe £150 for that extra 90w

2nd_time_buyer

arty688 said:

Spies said:

Perlight 295w are 1504x1002mm if that's any help. 

Cheers,

For example I have a space thats 1.6m x 2.1m (300mm taken off edges) so I could fit 2 x 295w or 1 x 400w panel.

Although it would be maybe £150 for that extra 90w

Go for the extra power you will kick yourself if you don't.

P.s. also with checking the degradation of the panels over time. More efficient n-type panels tend to have a lower degradation rate per year.

EricMears

2nd_time_buyer said:  This is normally claimed to allow thermal expansion of the panels. However, thinking about that, there is not just thermal expansion of the panel but also of the timbers in the roof, which I think might be more significant.

Thermal expansion of wood is considerably less than any metal.  In particular and since most solar panels seem to be on an aluminium alloy frame,  aluminium  expands 4 or 5 times more than (say) pine.

2nd_time_buyer

EricMears said:

2nd_time_buyer said:  This is normally claimed to allow thermal expansion of the panels. However, thinking about that, there is not just thermal expansion of the panel but also of the timbers in the roof, which I think might be more significant.

Thermal expansion of wood is considerably less than any metal.  In particular and since most solar panels seem to be on an aluminium alloy frame,  aluminium  expands 4 or 5 times more than (say) pine.

Good point. I was thinking more along the lines of expansion/shrinkage with water content. Albeit most of that would be a cross the grain. I hear the odd creak in our loft on a hot day which I assume might be related but perhaps not.