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Shed Install Questions

Lt.Dan

Solar Wizard
Joined
Dec 25, 2020
Messages
3,528
Location
Tulare, Ca
Hey guys, is anybody else putting all of their solar equipment in a shed near their home? I like the idea of having the batteries/inverters outside of the home in case of an incident, but the inverters will be atleast 100ft away from the breaker panel. I'm guessing they will be around 125ft. I'm interested in using 2 or even 3 of the new LVX6048WP when it comes out, I am also exploring Victron equipment and some others.

My concern is the wire run from the breaker panel to the inverters (to bypass power from the grid, through the inverters), and the run from the inverters to the critical loads panel, which will be in the same location as the main panel. This plan is still very shifty and ever-changing until I get closer, but I plan on somewhere between 12kw and 20kw of total output, and thats an awful lot of amperage over 125ft.

Anybody have any cool ideas or tricks for something like this? Or am I over thinking it, and should be just mounting the equipment in the garage (where the breaker panels are) on some hardie board?
 
For reference, this is an aerial view of the home. You can see the Green Dot is where the inverters will go, and the Red Dot is where the main panel is. I'm assuming i'll run it out of the shed, and through the attic of the home, and drop down into the garage/breaker panel.

Aerial View.jpg
 
Well I am not 100% sure of what your after with this question. Where are the solar panels going to be located ?
Guessing but appears you want roof mounted solar, routed to Powerhouse then to main house breaker panel. It does not appear you have space for a ground mount or anything else really. Maybe you have more property not shown ?

Some points:
Solar Panels output DC and DC is not great for long runs due to line loss, which is compensated for by increasing wire size and that gets pretty crazy pretty quickly ! DC Runs should be kept short as much as possible.

A Powerhouse to contain batteries (and to keep them within their thermal range) along with the Solar Components like SCC's & Inverters etc is not a bad idea... most people do not realize that the fans can make a hell of a racket (several people replace the fans with good axial ball bearing fans that are silent) as the cheap computer type box fans with roller bearings are plain obnoxious (and cheap as snot). From a Powerhouse AC Power can run hundreds of feet without major issues BUT of course must be wired properly for the load & distance deration. BUT you would also have to run a Line from the Main Panel back to the powerhouse to serve as backup battery charging to the inverter/charger subsystem (Typically a 120V/20A Circuit can handle that nicely).

Grid Connected:
Do you mean just to be able to use grid to charge batteries IF they need it ? or
Do you want to get into a FIT (Feed In Tariff) program ? That changes things a LOT. more permits, rules & regs, insurance co "happiness" factor (they are a PITA) etc etc $$$ etc....

3 of the LVX6048WP would give you a max of 18,000W. 18kw ÷ 120VAC=155A / 240VAC=75A
* Uncorrected for inneficiency.

Simplest is to just use a Grid Circuit as a Backup Charge Input line and nothing else.
Then wire your "Essential Circuits" to a Sub-Panel which is fed by the solar system and then it can take care of everything on that panel exclusively from Solar & Battery and should there be lack of sun etc, then it can charge the batteries from the supplied grid line.

My own setup uses a 14x6 Hyper Insulated Powerhouse (I'm deep north) which is 75' from my home and 35' from the Solar Array. Solar Array to Powerhouse is DC and then in powerhouse all goes to AC & out from there. With future upgrades in mind, I ran 6/3 AWG & 8/3 AWG NMWU Wire in 4" Insulated Conduit from powerhouse to house underground.

BTW: You mention Fireboard / Hardie Board... For 1/2 the cost and twice the protection look at Magnesium Oxide Board !
REF: https://www.ambientbp.com/mgo-magnesium-oxide-boards-magboard.php
*PS, Makes an excellent Tile Backer too and a 4'x8' sheet costs less than a 4'x4' fireboard (cement board).

Hope it helps, Good Luck.
 
That is quite a distance. I considered something similar and actually chose to utilize a shed instead of a Detached garage because the shed was actually a lot closer.
 
Well I am not 100% sure of what your after with this question. Where are the solar panels going to be located ?
Guessing but appears you want roof mounted solar, routed to Powerhouse then to main house breaker panel. It does not appear you have space for a ground mount or anything else really. Maybe you have more property not shown ?
Solar will be located on the roof. The roof and patio overhang could probably house more than 15kw of solar, but we will see once we get some plans made. The LVX6048WP also has an PV VOC rating of 600v, so that should be no problem.
Some points:
Solar Panels output DC and DC is not great for long runs due to line loss, which is compensated for by increasing wire size and that gets pretty crazy pretty quickly ! DC Runs should be kept short as much as possible.

A Powerhouse to contain batteries (and to keep them within their thermal range) along with the Solar Components like SCC's & Inverters etc is not a bad idea... most people do not realize that the fans can make a hell of a racket (several people replace the fans with good axial ball bearing fans that are silent) as the cheap computer type box fans with roller bearings are plain obnoxious (and cheap as snot). From a Powerhouse AC Power can run hundreds of feet without major issues BUT of course must be wired properly for the load & distance deration. BUT you would also have to run a Line from the Main Panel back to the powerhouse to serve as backup battery charging to the inverter/charger subsystem (Typically a 120V/20A Circuit can handle that nicely).
This is another concern is noise. These MPP inverters are not known for their silence! And yes, I will need to make the run in both directions! My only concern is I need to be able to run full load in "bypass" mode. So, a 120v/20a circuit won't support the full load obviously. What happens when the batteries reach 0% and I still have a 3000w load? The 120v/20a circuit definitely isn't going to carry it! I'm thinking I will need to run obnoxious wiring both to/from the inverters if I don't want to sacrifice output.
Grid Connected:
Do you mean just to be able to use grid to charge batteries IF they need it ? or
Do you want to get into a FIT (Feed In Tariff) program ? That changes things a LOT. more permits, rules & regs, insurance co "happiness" factor (they are a PITA) etc etc $$$ etc....
No grid ties, I don't want to deal with all the headaches that come with it... like you mentioned.
3 of the LVX6048WP would give you a max of 18,000W. 18kw ÷ 120VAC=155A / 240VAC=75A
* Uncorrected for inneficiency.

Simplest is to just use a Grid Circuit as a Backup Charge Input line and nothing else.
The only bummer with these MPP AIO units is you cannot use the incoming grid circuit to charge the batteries at the same time you are inverting power and using it. You can either use the incoming grid circuit to power your loads and charge the battery (if the grid circuit is enough for that, like stated above), or you power the loads with Solar/Battery. No in between.
Then wire your "Essential Circuits" to a Sub-Panel which is fed by the solar system and then it can take care of everything on that panel exclusively from Solar & Battery and should there be lack of sun etc, then it can charge the batteries from the supplied grid line.

My own setup uses a 14x6 Hyper Insulated Powerhouse (I'm deep north) which is 75' from my home and 35' from the Solar Array. Solar Array to Powerhouse is DC and then in powerhouse all goes to AC & out from there. With future upgrades in mind, I ran 6/3 AWG & 8/3 AWG NMWU Wire in 4" Insulated Conduit from powerhouse to house underground.
Smart thinking ahead, thanks for the idea!
BTW: You mention Fireboard / Hardie Board... For 1/2 the cost and twice the protection look at Magnesium Oxide Board !
REF: https://www.ambientbp.com/mgo-magnesium-oxide-boards-magboard.php
*PS, Makes an excellent Tile Backer too and a 4'x8' sheet costs less than a 4'x4' fireboard (cement board).

Hope it helps, Good Luck.
I will look into it!

I'm basically debating if it is worth the extra cost to put everything out in the shed, or do I save the time, labor, and wiring costs and put it in the garage next to the main panel and then making it safe/fireproof etc.
 
If you size the wire correctly you should have no problem. 4/0 aluminum is rated over 200 Amps, so I'm sure you can find something.
I'm also hoping someone with much more knowledge on here can jump on with other ideas, such as step-up/step-down transformers to reduce current and use much smaller wire? Is it feasible? Or am I forced to run wires totaling the size of my wrist?
 
Wire sizing was the issue I was thinking of as well. I am also looking at the same inverter, but did not know the max output wire size of the LVX6048wp. If large enough than a long run shouldn't be a problem and I may also be changing up my plans. I figure at least in a shed it would be less of a potential hazard to more important and costly structures.
 
I figured I would probably run out of the 3x LVX6048WP's into a common bus bar (or Polaris connectors) and output the much larger wire from there.

Doing the math, running copper 2awg for my 2 hots and neutral, and a 6awg ground conductor, it will cost about $1000 one way.

Thats probably enough for me to just put it in the garage. Lol
 
I keep my batteries inside the house. They're server rack LFPs, I like to see the LEDs and the temperature is more controlled.
The AIO I keep in a "cupboard" outside, just on the other side of the wall where the batteries are. Under the roof. Because of the fan noises, yes.
The wall is well insulated, I don't hear it.
The generator (small and quiet, but still noisy) under a box under a tree some 30 metres away from the house.
-
 
I figured I would probably run out of the 3x LVX6048WP's into a common bus bar (or Polaris connectors) and output the much larger wire from there.

Doing the math, running copper 2awg for my 2 hots and neutral, and a 6awg ground conductor, it will cost about $1000 one way.

Thats probably enough for me to just put it in the garage. Lol
Can't beat aluminum wiring at this gauge... https://www.lowes.com/pd/Southwire-2-2-2-4-Black-Stranded-Al-MHF-Use-2-Cable/5002300757

Even getting 2awg Alu wire at lowes, a full 125 feet is only $260. Probably could get it much cheaper at a local supply place...

2awg aluminum wiring makes for a 2.5% voltage drop at 75a. Not that bad.

I wonder if the LVX6048WP can be set to output 127v like the LV6548's, then voltage drop would be less of an issue...
 
1 Grand is POLITE, there will be more, add 25% easy for BOS.

Many folks build a "Closet" of sorts not only to contain the noise but also as a safe cabinet as such.
In such an instance air management comes into play (and also a source of Axial Ball Bearing Fans) comes into play so have a look here: https://www.acinfinity.com/ I use their Smart USB Fans with digital controllers and their AC Axial Fans as well.. some of the best out there & well priced too. BTW, they also have the smaller Axial fans you CAN use to replace the noisy factory crapadoodle fans supplied.

Sorry but I dunno how MPP'S handle charge / pass-through or if it's a bypass. I do not own MPP or Growatt as I am a Samlex & Midnite user which are quite a bit different. Samlex does Passthrough very well BUT they do not make an AIO "yet"... sorry NDA's kick in.

For your main power lines from Solar to House should be Bigger than what you project at this time. Almost everyone puts up a system, thinking it's big enough and 80% want to upgrade within a year because they realized they way underestimated their use. EVERYONE Thinks they are more frugal than they really are. To that end, I always recommend that if you figure your need X Watts/Amps you had better buy for "Y" and if really unsure buy for "Z" (Think in terms of the alphabet) and build at least 1 Step above your estimate, most importantly the things you will NOT want to change / upgrade later at great expense. The reason why I ran 6/3 & 8/3 inside a 4" conduit that can take even bigger wire if needed. I do NOT want to dig up a 8' deep trench to replace wires ... yes 8' deep ! Hell of a lot easier to pull through a conduit.

Another point to ponder...
You mention 3 Paralleled AIO's for 18,000W.
Appreciate the standby losses are additive per unit and the other trade-offs that go with it.
AIO's while great for simplified installations are not necessarily the most efficient or the best at what they do, they ARE a set of compromises and that my friend is a FACT and no way around it. I really urge you to look at the "operating costs" in power, management and the upgrade interlinking paths.

PS: Step Down/Up converters & transformers are all energy wasters and should be avoided whenever possible, built to target only and step-down only when needed for auxiary devices, (typical not residential applications). I have seen such go terribly wrong and create havoc that no one wants.
 
For a lot less than that you can even get a security cabinet (with fans) - basically a safe - and bolt it to the house.
-
 
1 Grand is POLITE, there will be more, add 25% easy for BOS.
That 1 grand was for only 1 way as well! Aluminum seems much more feasible.
Many folks build a "Closet" of sorts not only to contain the noise but also as a safe cabinet as such.
In such an instance air management comes into play (and also a source of Axial Ball Bearing Fans) comes into play so have a look here: https://www.acinfinity.com/ I use their Smart USB Fans with digital controllers and their AC Axial Fans as well.. some of the best out there & well priced too. BTW, they also have the smaller Axial fans you CAN use to replace the noisy factory crapadoodle fans supplied.
This is probably what I will end up doing. I'm a metal fabricator and manage a CNC laser/waterjet shop, so making a "safe" is not difficult in the slightest. I have used ACinfinity before, and they are great!!
Sorry but I dunno how MPP'S handle charge / pass-through or if it's a bypass. I do not own MPP or Growatt as I am a Samlex & Midnite user which are quite a bit different. Samlex does Passthrough very well BUT they do not make an AIO "yet"... sorry NDA's kick in.
Ah c'mon, quit hiding! haha
For your main power lines from Solar to House should be Bigger than what you project at this time. Almost everyone puts up a system, thinking it's big enough and 80% want to upgrade within a year because they realized they way underestimated their use. EVERYONE Thinks they are more frugal than they really are. To that end, I always recommend that if you figure your need X Watts/Amps you had better buy for "Y" and if really unsure buy for "Z" (Think in terms of the alphabet) and build at least 1 Step above your estimate, most importantly the things you will NOT want to change / upgrade later at great expense. The reason why I ran 6/3 & 8/3 inside a 4" conduit that can take even bigger wire if needed. I do NOT want to dig up a 8' deep trench to replace wires ... yes 8' deep ! Hell of a lot easier to pull through a conduit.
Maybe should setup wiring for 100a possibility. Always smart to overengineer.
Another point to ponder...
You mention 3 Paralleled AIO's for 18,000W.
Appreciate the standby losses are additive per unit and the other trade-offs that go with it.
AIO's while great for simplified installations are not necessarily the most efficient or the best at what they do, they ARE a set of compromises and that my friend is a FACT and no way around it. I really urge you to look at the "operating costs" in power, management and the upgrade interlinking paths.
Definitely, I am working out other as well, and really eyeing the Victron 48v/10kva Quattros, but even 2x of them is 120w standy, and 3x MPP's will be 180-200w. Not the end of the world there, but the efficiency will be huge because the Quattros are 94%, and the MPP is only 91% at best. That will add up pretty quick.

But, the Victron is 3-4x the entire cost. I could put a lot more money into batteries and solar for that... I'm also interested in SolArk and others...
PS: Step Down/Up converters & transformers are all energy wasters and should be avoided whenever possible, built to target only and step-down only when needed for auxiary devices, (typical not residential applications). I have seen such go terribly wrong and create havoc that no one wants.
Good info, thank you.
 
I started with an 88% Efficient inverter, then went to the Samlex at 94% and a very low standby (not sleep) and wow, yep, it makes a difference. * I am 100% off-grid so things are a tad more noticeable. Once you get into this, a side effect happens that many often don't mention because they think it's "just them" but you become far more "Watt Aware" and things in your home...

ACinfinity rocks ! I started using their stuff 15 yrs ago ? never ever a problem. Great support too.

Wiring for 100A (well 125 to account for losses & overage) should cover you pretty well for a lot of things.

MPP, Victron, Growatt and a few others (several not generally mentioned here) could be considered. I am Very Happy to see that you are considering the efficiencies and idle consumption rates because it really does make a difference, and far too many do not think that through.

Now just a "nit pick" in a sense.
You want to install on the roof and figure 15kw of panel. Have you done the angles calculations to see how good the exposure will be for solar ? Because even when at the optimal angles you never get the label rating but you "may" get close. Typically 80% is the best one can hope for from a well-positioned install. Roofs are notoriously not the best for angles etc, well pending on how close to the equator you are I suppose.
 
I started with an 88% Efficient inverter, then went to the Samlex at 94% and a very low standby (not sleep) and wow, yep, it makes a difference. * I am 100% off-grid so things are a tad more noticeable. Once you get into this, a side effect happens that many often don't mention because they think it's "just them" but you become far more "Watt Aware" and things in your home...

ACinfinity rocks ! I started using their stuff 15 yrs ago ? never ever a problem. Great support too.

Wiring for 100A (well 125 to account for losses & overage) should cover you pretty well for a lot of things.
100a will be way more than enough for me. The house only has 100a service, and I don't plan on running the AC with the inverters either, but I could in the future If I need to. My max load should probably never exceed 50a. I originally will probably start with 1x LVX6048WP, and slowly transfer loads from the main service to the critical loads panel as I add more inverters/battery capacity. I feel this is smarter to do rather than go all-out and get overwhelmed.
MPP, Victron, Growatt and a few others (several not generally mentioned here) could be considered. I am Very Happy to see that you are considering the efficiencies and idle consumption rates because it really does make a difference, and far too many do not think that through.
Now just a "nit pick" in a sense.
You want to install on the roof and figure 15kw of panel. Have you done the angles calculations to see how good the exposure will be for solar ? Because even when at the optimal angles you never get the label rating but you "may" get close. Typically 80% is the best one can hope for from a well-positioned install. Roofs are notoriously not the best for angles etc, well pending on how close to the equator you are I suppose.
Well I do run a small crypto mining farm from my home as well, and I know I will never cover 100% of all the equipment's energy requirements, but everything helps, so I plan on just covering every inch of the house that I can. From the picture I posted above, the right side of the roof (largest side) is actually pointing about 30-35* South-Southeast. Meaning I'll get very good solar in the morning and it will taper off towards end of day. Like you said, I'm limited because of the fixed roof, but I'm just shooting for as much as possible. I also will have the RV parked on the side of the house with 2.8kw on the roof (flat, but again, still something).
 
All of the roof angles around here are 3/12, while not ideal, and combining different sides of the roof can beneficial even though not super efficient. With panel prices, especially used, one could cover just about everything that even has an east/west facing roof and still get some noticeable increases in power generation and a nice relatively flat power curve throughout the day. The added benefit are these shingled roofs will last a lot longer than the 30 year rating.

I think your plan is solid. And to add, that aluminum wiring is pretty good price wise for very long runs. Utility uses it after all, though theyve got it suspended from the poles often times and I'm sure weight and not just cost is a factor.

I think looking into the efficiency of inverters is a wise move also, especially for the large loads that dont get used often, perhaps a large powerful inverter that only needs to be turned on during the 50 or even 30amp loads would be worth it.
 
I have a new plan, using 2x Victron Multiplus 2's 48v 3KVA models. I have thought more about what loads I have and for the length of time. In all reality 20-22 hrs of the day will be spent under 3kw. The nice thing about the multiplus 2 is the ability to powerassist up to 50a. So if the load is 10kw, the inverter will supply max power (2400w according to data sheet), and the remaining 7600w will come from the grid.

Using these 2 MultiPlus 2's will greatly reduce cost of the overall system, but still cover 95%+ of my loads, and I still am not limited on output. Both units can bypass a max of 100a, which is what the main breaker panel is rated for!

I also have decided due to simplicity to just keep it in the garage and take extra precautions to prevent damage if there was a fire or something.

I mean 95% efficiency and 11w idle consumption. Cmon how do you beat that?
 
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I sat down with a local solar installer yesterday just to pick their brain about local code and if they would be willing to do a partial install (ie, they install the panels on the roof for me, and I'll take care of the rest), and I think I offended them by asking lol. After trying to explain that I am not attempting to feed back to the grid, and I am planning on going with an "off grid" system, they thought I wanted to get rid of my power bill 100% and to cut off the connection from the electric company. I told them several times, "No, I just dont want to feed back to the grid". Everytime I said something like that, they would kind of look at me funny, "why would you not want to do that???". They also were saying that there is still a lot of permits/regulations I have to follow, even if I'm not feeding back to the grid, but they wouldn't tell me what permits, or where to go from here.

I also asked them for a full quote on them doing an entire 15kw array, which they said they would get me today. I'm fully prepared for a $40k estimate, but we'll see.

I guess I need to do more research and find out who to talk to about permits/regulations for off grid solar systems.
 
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