Question about Solar Design

[BerMuc]

Just got my design back from Tesla, and I'm somewhat disappointed. It looks like they split the panels between south and north facing, although I think they could get more panels on the south side.

Wanted to see what the community opinion is about this? It seems pretty counter-intuitive to me to have the panels north facing - do they even generate anything in Winter with a steeply pitched roof? Does anybody have experience with a 50/50 split system between north and south?

 

[NXN-P3D]

Yeah - there’s not enough space on your south-facing roof. They can’t add more there as you have to keep some distance from the edges and pitches (code here is 1ft for fire crew).

You can ask to arrange those vertically and see if you can add 2 more (1 on each side).

I have south and west facing - north would be useless unless it’s a flat roof.

 

[jboy210]

Yeah - there’s not enough space on your south-facing roof. They can’t add more there as you have to keep some distance from the edges and pitches (code here is 1ft for fire crew).

You can ask to arrange those vertically and see if you can add 2 more (1 on each side).

I have south and west facing - north would be useless unless it’s a flat roof.

I would not call North facing useless unless the slope was steep. Rather only useful a few months of the year. We have some of our active tiles on north facing planes and they do contribute part of the year. Fortunately this is the summer and they help cover the A/C load.

 

[Vines]

I would not install on straight north-facing surfaces more than 3:12. Not sure what your local fire codes are, but it looks like they left some room on the south roof which could be used. Many jurisdictions like to assume more restrictive fire rules but unless they have adopted some local ordinances they should stick to the CBC and the CFC.

The Zep system that Tesla uses works much better in landscape, but the roof in this case looks like portrait might allow usage of those unused surfaces at the SE and SW edges.

 

[BerMuc]

We are in SoCal, so yeah probably not useless but definitely much less in Winter. Checking today, backside of the house has full sun coverage for the past few hours, so it might not be that bad. I wish I would have checked in December.

Pitch is between 3:12 an 4:12.

 

[Vines]

We are in SoCal, so yeah probably not useless but definitely much less in Winter. Checking today, backside of the house has full sun coverage for the past few hours, so it might not be that bad. I wish I would have checked in December.

Pitch is between 3:12 an 4:12.

Oh, at that slope the issue is much smaller. In SoCal, even 4:12 is probably still worth it.

 

[jboy210]

We are in SoCal, so yeah probably not useless but definitely much less in Winter. Checking today, backside of the house has full sun coverage for the past few hours, so it might not be that bad. I wish I would have checked in December.

Pitch is between 3:12 an 4:12.

I am not sure if it is always accurate, but you can optionally draw the solar layout design options and see the resultant yields for each month on the PVWatts site. It was pretty close for us.

 

[tomuo]

I think it makes sense in Southern California to use that North side, if there's no way to squeeze more on the South.
It'll be a trickle in Winter, but in Summer it should give you enough to carry you through the hottest part of the day avoiding pulling peak priced power.
(via pre-cooling if you have only solar).

Over the next 10 years the peak pricing will only go up, so the ROI on the avoided cost is good.

 

[Katdeskinner]

Just got my design back from Tesla, and I'm somewhat disappointed. It looks like they split the panels between south and north facing, although I think they could get more panels on the south side.

Wanted to see what the community opinion is about this? It seems pretty counter-intuitive to me to have the panels north facing - do they even generate anything in Winter with a steeply pitched roof? Does anybody have experience with a 50/50 split system between north and south?

View attachment 781953View attachment 781954

They designed my panel to be in shade of north side of two story neighbors. I had a redesign on my east west panels to go 6 on east 6 on west, out of any shade. Forget to say they had put all 12 on west facing. Then another redesign of 6w/6e facing. Haven’t got pto, but I believe my 4.8 kw system is doing ok.