Solar PV advice

[Richard77]

Putting my plans to cover the whole roof in panels on hold for the time being now and just sticking to putting some panels on the garage.

Costs were getting a bit too much.

I'm going to stick with the 12kW inverter though.

Could I ask everyone's opinion on how many panels I could get on the garage? Does there need to be a certain gap from the edge/ridge of the roof even if it's just a garage?

Here are the exact measurements:



The roof closest to the house narrows a bit and is a bit smaller than the other roof.

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Maybe a layout like that and get 4 each side? 1722mm long panels. With one horizontal were the roof narrows too much in bottom right corner.

Installer only wants 2x horizontal each side.

Any ideas?

Thanks

[Fueltheburn]

If I am reading those dimensions correctly it is just over 11m long.
You could put 9 panels on each side vertically. This is accounting for a panel over 1.1m wide with clamps in between each panel and an end clamp with a bit of spare rail at the end.

The panel can overshoot the roof bottom and top by 200mm when I was looking at the plannig portal but this will render your gutters obsolete and all the water runs off the panels onto the floor.

If the above doesn't bother you then I would say 18 panels total over 2 strings for somewhere between 7 and 9kW installed capacity.

[nowty]

If I am reading those dimensions correctly it is just over 11m long.
You could put 9 panels on each side vertically. This is accounting for a panel over 1.1m wide with clamps in between each panel and an end clamp with a bit of spare rail at the end.

The panel can overshoot the roof bottom and top by 200mm when I was looking at the plannig portal but this will render your gutters obsolete and all the water runs off the panels onto the floor.

If the above doesn't bother you then I would say 18 panels total over 2 strings for somewhere between 7 and 9kW installed capacity.

Your not reading it right, its just short of 6m long, but I agree that 200mm overshoot is OK with planning rules and 4 on each side is certainly possible.

[Fueltheburn]

Just as an additional thought. If you are looking at the Sunsynk 12kV. What is the startup voltage for this unit?
Might be a tad high for the small amount of initial panelling.

[Fueltheburn]

Just as an additional thought. If you are looking at the Sunsynk 12kV. What is the startup voltage for this unit?
Might be a tad high for the small amount of initial panelling.

The spec sheet states 125v for startup on the 12kV unit. If only 4 panels per string this may be an issue.

[Richard77]

If I am reading those dimensions correctly it is just over 11m long.
You could put 9 panels on each side vertically. This is accounting for a panel over 1.1m wide with clamps in between each panel and an end clamp with a bit of spare rail at the end.

The panel can overshoot the roof bottom and top by 200mm when I was looking at the plannig portal but this will render your gutters obsolete and all the water runs off the panels onto the floor.

If the above doesn't bother you then I would say 18 panels total over 2 strings for somewhere between 7 and 9kW installed capacity.

I wish it was that big mate hehe

Both roofs are slightly different size. They narrow a bit towards the right hand side. 5.83m wide on the roof furthest away from house and 5.74m wide nearest to house. The problem it seems is that the nearest roof to house is 1.77m to the ridge narrowing to 1.72m and the roof furthest away is 1.8m narrowing to 1.76m.

[Richard77]

Just as an additional thought. If you are looking at the Sunsynk 12kV. What is the startup voltage for this unit?
Might be a tad high for the small amount of initial panelling.

The spec sheet states 125v for startup on the 12kV unit. If only 4 panels per string this may be an issue.

All the SunSynk's seem to be 125v startup voltage.. would need at least 4 panels I think.

[Richard77]

If I am reading those dimensions correctly it is just over 11m long.
You could put 9 panels on each side vertically. This is accounting for a panel over 1.1m wide with clamps in between each panel and an end clamp with a bit of spare rail at the end.

The panel can overshoot the roof bottom and top by 200mm when I was looking at the plannig portal but this will render your gutters obsolete and all the water runs off the panels onto the floor.

If the above doesn't bother you then I would say 18 panels total over 2 strings for somewhere between 7 and 9kW installed capacity.

Your not reading it right, its just short of 6m long, but I agree that 200mm overshoot is OK with planning rules and 4 on each side is certainly possible.

Will it pass the MCS regulations if have an overshoot?

[Fueltheburn]

Just skimmed the below document and there is no mention of overhang in the MCS standards.



The 200mm maximum overhang I have seen was referenced in planning permission portals and was alongside the distances and proximities to edges of property borders etc in the land and country documents.

[Richard77]

Just skimmed the below document and there is no mention of overhang in the MCS standards.

The 200mm maximum overhang I have seen was referenced in planning permission portals and was alongside the distances and proximities to edges of property borders etc in the land and country documents.

Found this in the MCS standards document, unsure if it applies to garage roof though.

5.9.7 Solar PV modules should not be mounted within 400mm from any edge of a domestic
roof unless specific measures are taken to:
• Resist the increased wind uplift forces in the edge zone through additional fixings
and, where necessary, additional roof timbers for those fixings
• Ensure ridge-tiles remain secure
• Ensure rainwater run-off patterns are not affected
• Ensure build-up and shedding of snow cannot cause injury or property damage
• Reduce nuisance from wind noise