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I'm at 30latitude roof is 26deg and faces 150(SE) would you guys bother with a ground mount?

dudeinthewoods

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I'm at 30latitude roof is 26.5deg and faces 150(SE) would you guys bother with a ground mount?

Debating mounting all these panels on a section of roof facing 150 degrees and 26.5 degrees.

I can do that and have them out of the way or spend a lot more money build something like a carport and have it in the way.

What are you guys thinking? Shouldn't be a huge huge hit should it? I'm off grid have no power connection so get it all from solar.

I could probably do a slight lift in one end of solar and get the extra 4 degrees but can't rotate the house :)
 
The house is a pretty handy place to mount panels. Its not a awful arrangement pointing to 150 deg. The slope looks fairly well matched to your latitude.
Not knowing ANYTHING about your situation or goals, its really hard to make recommendations.

In general, a ground mount can be pointed to a better direction and even in multiple directions (some panels favoring east, some west to harvest all day long). A ground mount could also be made to adjust for the seasons though i am not sure how much effort i would put into that.

A carport sounds handy and not in the way at all. I've seen patio shade from solar panels that made a patio usable during the day.

Panels are big and cheap so i won't even suggest tracking the sun.

Sorry to ramble, not sure this was helpful at all.
 
Thanks it was.
I've currently got 20kw in panels may get another 20kw. I've got 3000~ AH@48v. But selling a bunch of that off as it's overkill.

Currently I've just got all the panels flat so anything is an improvement haha. I like the idea of some west facing too.

Carport is cool but the angle sucks. It's a weird looking carport if I do it haha.
 
Carport is cool but the angle sucks. It's a weird looking carport if I do it haha.
You should google "solar carports" or go on Alibaba and search "solar structure".
You have a LOT of solar panels so having them angled perfectly may not be as important as you think. The world
has a lot of panels mounted flat (RV's, carports, awnings, ...)
 
Watching, as I have been considering the same problem. I have a very similar situation as far as house orientation goes. I have been considering a solar carport/shade structure too. But, for now I only want to be able to run a few circuits during power outages, so don't need nearly the number of panels as you.
 
Maybe more concerned not being pointed 180 but 150 isn't horrible.
You have not revealed your use case but if you can get by with charging only in the morning that is easiest.
That would involve a LOT of charge current in the morning (and nothing in the afternoon).
Having to charge a lot will require planning on getting an SCC that maximizes what your battery bank (unspecified)
can handle. And your battery use case (unspecified) will be dictated by morning charging.

It seems that having 2 different arrays makes sense for you (especially since your house will support the east facing array). This would allow you to harvest sun all day long with smaller (cheaper) equipment and charge batteries in a gentler way.
 
You have not revealed your use case but if you can get by with charging only in the morning that is easiest.
That would involve a LOT of charge current in the morning (and nothing in the afternoon).
Having to charge a lot will require planning on getting an SCC that maximizes what your battery bank (unspecified)
can handle. And your battery use case (unspecified) will be dictated by morning charging.

It seems that having 2 different arrays makes sense for you (especially since your house will support the east facing array). This would allow you to harvest sun all day long with smaller (cheaper) equipment and charge batteries in a gentler way.
I could absolutely put another set of panels either on the opposite side which would be 330degrees which is pretty terrible haha or do something to charge early.

I can't imagine the power will drop that early at 150deg. It looks to be pretty steady but I'll know after the first day haha.

I've currently got 850ah 48v lifepo4 batteries that I'll keep and another 3000ah in lead acid I'm selling via a friend that dont really play in.

I was thinking to try and get as many hours of sun early and late as everything is on solar. Fridge etc, water heater isn't but I'd prefer it were.

I'm thinking it may make sense to just get a few more panels it hits right away and later. Could even go at a steeper angle as they'll really only get direct sun the first few hours.

On the controllers I'm currently using a few make sky blues. 60a I've got a a 50kw SMA tri-core1 I'm wiring in gotta decide on how to charge up though. I have some sunny island at my friend's house but was also selling those.
Still figuring out this transition to the tricore and components as I go.
 
Tri-core (is that STP 50-US-41?) should be good for a large 3-phase system. It runs at higher voltage, so you'll need to step down voltage either to lower voltage battery inverter (Sunny Island), or there are higher voltage 3-phase battery inverters (SMA sells for Europe and elsewhere) and you'll have to step down to house loads.

Probably up to 36 kW on the tri-core would work with 3x SI6048.
 
Tri-core (is that STP 50-US-41?) should be good for a large 3-phase system. It runs at higher voltage, so you'll need to step down voltage either to lower voltage battery inverter (Sunny Island), or there are higher voltage 3-phase battery inverters (SMA sells for Europe and elsewhere) and you'll have to step down to house loads.

Probably up to 36 kW on the tri-core would work with 3x SI6048.
You got it.

It's 277/480 which isn't ideal for what I want but it's not the end of the world.

I have a decent shop with some 3 phase stuff and the nerd in me likes 3 phase.

I was thinking SI6048 but I figured I need 6. Maybe I don't. I thought they maxed out at 6kw. Curious why you think I'd need 3 and love to spend less.

I'd have to step down as they're 110v on the AC coupling. Wish they could take 277 in.

It seems cleaner that way to just have everything after the transformer. I'm not enjoying transformer shopping though.
 
SI6048 can be configured as 1, 2p, 3p, 4p, 2s, 2s2p, 3Y
Each one can deliver just shy of 6kW continuous at 25 degrees C, and 11 kW surge for 3 seconds to start motors.
Each one can handle about 12 kW of AC coupled PV, so 3 of then making 120/208Y with step-up transformers could handle 36kW.
If grid-tied, can only backfeed 6.7 kW per SI6048 due to 56A relay.

You can't combine 6 directly, but with a multi-cluster box you can have two or more groups of 3.
What I'm not clear on is how those combine, and where AC coupled PV goes. If Tri-Core was on the island side, it would have the backfeed limit of 6.7 kW per phase. I think it goes on a common 3-phase network feeding the grid input of the two clusters, from drawings in the following brochure. Probably both configurations work and can be used simultaneously, within current limits.


If I was you, I'd keep all the SMA stuff for expansion or spares.

Looks like the Tri-Core has voltage adjustment range, 277 nominal AC voltage range 244 V…305 V
So a 120/240V transformer might be sufficient. I picked up some 9000VA toroids that came out of UPS, I think. They have a 240V winding and two 120V windings. I think some other taps on those. Maybe you can find something like that.

Lithium, you'll want a compatible BMS.
If you have two clusters of Sunny Island, one could be lithium and the other lead-acid.
 
Makes sense on the SI. Didn't know it could take more AC coupled.

I think the voltage adjustment you're talking about is just the alarm setting if it's out of range. What your tolerance is.

If I'm wrong and I can just dial it down to 240 and then do each phase step down that would be fine.

I was just thinking it's 277/480 wye but could you just leave the neutral and do a 480 delta to 120/208 wye? I'm thinking maybe because it can connect to 480 grid without neutral.

If that's the case could get a 480delta to 120/208wye and then just run that end to the panel. Those are a lot more plentiful and economical.

For example this guy:

Of course could run that 120 to the SI units.
 
I think voltage is adjustable. Everything they build is. But I did "brick" one inverter with a bad setting that caused an error, and could never clear.

That's cheap, and has 432V to 504V taps.

What I'm not up on is the losses of those transformers. With excess PV panels and GT inverter, inefficiency doesn't matter, but how much power is consumed no-load? That's a drain on the battery. (could disconnect with a relay at night)

Toroids are more efficient, but that isn't much more expensive than the first 9000VA I bought. The other two were bargains.

I've occasionally seen the multi-cluster controllers for sale. You could power a village.
With just one PV inverter, you do have a single point of failure. Might want some over inverters or DC coupled PV as redundancy.
 
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