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diy solar

Trying to choose an AIO for my Skoolie

The_Kobayashi_Vroom

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So I had thought that doing 2 - MPP LV6448 and running them parallel for a 13Kw output would be a great option for us on our skoolie, but when I look at what we would need to have in order to mount the 2 + the breaker/fuse box thing with the proper spacing - I don't think we have that space. I watched a video of Will installing 1 of the MPPs and it looked so much easier than doing it all individually with my lack of experience..... but without the space for it - that's not an option - unless the way I watched on the YT video isn't the only way we could install it.

So I started looking at the Growatt 48V SPF 5000 ES 5KW with reducing our spreadsheet a lot - because that is the highest one I could find that is only 1 inverter/charger in one and maybe combining it with the EG4 48 V 100aH battery(ies).

Does anyone have any suggestions on if I am going the wrong direction here? We are still doing some framing, but I don't know if we can make adjustments to account for 2 of the MPPs - which is honestly the most ideal of options to build for bigger than we will need, but if I can always add on to the Growatt and add on the EG4s.... maybe I should start out with what I know I can handle in our bus - and then add on to it when we are somewhere permanent?

Thanks in advance,
Amanda
 
Budget All-In-Ones are an attractive seeming option when you are new and find the details overwhelming (and one might be the right option for you), but be sure to look into the idle power draw of up to 70W (so 140W if you have two of them). If they are on 24/7 that is up to 3360Wh a day. For a solar limited application like a vehicle where you can only fit a finite and limited amount of PV panels on the roof, AIO's may not be the best solution--or at least not the cheaper/high idling ones.
 
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Budget All-In-Ones are an attractive seeming option when you are new and find the details overwhelming, but be sure to look into the idle power draw of up to 70W (so 140W if you have two of them). If they are on 24/7 that is up to 3360Wh a day. For a solar limited application like a vehicle where you can only fit a finite and limited amount of PV panels on the roof, AIO's may not be the best solution.
I did calculate that into my energy audit with the help of other members of the board on the board for Newcomers. My bus is very large and if I include my wants and needs - this is what it looks like
1635983087092.png
 
I've yet to see an all in one that handles the neutral/ground bond appropriately for a mobile setup.
Most inverter/chargers get this right though.
 
I did calculate that into my energy audit with the help of other members of the board on the board for Newcomers
I'm not sure you did actually. I'm not positive but from the screenshot, I can see that you did factor in the conversion efficiency of 90% (which is the peak efficiency just so you know), but there is also a second form of inefficiency with inverters called 'no-load' or 'idle' power consumption this is the energy that the inverter burns just sitting there regardless of whether it is running or not. For the LV6548 that you mentioned, the spec sheet lists a peak efficiency of 91% and a no load of <70W. The MPP may or may not have some eco mode that might reduce that no load draw when the inverter is sitting idle.

I will find a spec sheet for the Growatt unit, and see if I can find the no-load draw for it, as it may be better.
edit: looks like the Growatt spec sheet does not state what the no-load consumption is.

I am not actually positive if the excel sheet takes into consideration no-load consumption, probably @FilterGuy could tell us though.
 
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I am not actually positive if the excel sheet takes into consideration no-load consumption, probably @FilterGuy could tell us though.
No.... that is not built into the spreadsheet. I guess if I assume the inverter load is the same whether loaded or not I could add it as a 24x7 load.
70W x 24hrs is 1689Whrs. That is a lot.

As an aside, the spreadsheet is conservative and the actual usage will typically be less than the calculations unless they are measuring all of the loads fairly accurately.
 
No.... that is not built into the spreadsheet. I guess if I assume the inverter load is the same whether loaded or not I could add it as a 24x7 load.
70W x 24hrs is 1689Whrs. That is a lot.
It is a lot--MPP has notoriously high idle consumption--and I believe she is considering 2x all-in-ones, so that would be 3360Wh total.

I don't know if you should or shouldn't add it to the spreadsheet, since its so variable--variable in how people use their inverters (always on vs not), and variable in terms of eco modes and the like--makes it hard to estimate it would seem. This example of 2x70W idle, is somewhat of an outlier I think.

One reason I dont think the MPP units (or maybe cheap AIO's in general I'm not sure) are not great choices for mobile/solar limited builds, since a not-insignificant portion of PV would have to be devoted to just offsetting the inverters usage.
 
One more thing, having just skimmed your other thread, it strikes me that you are adaptable, willing and able to learn and take in new information, and capable. If your main reason for wanting an AIO is because added complexity of discrete components seems daunting, I think its at least worth considering the pros/cons, because I think you would totally be capable of designing around discrete components and the added complexity isn't really that much. Cost can also be a factor though. The cheap AIO's are an attractive price point, but one of the tradeoffs is the high idle.
 
it strikes me that you are adaptable, willing and able to learn and take in new information, and capable.
Thank you for saying that - I am definitely willing and able to learn. I don't have the confidence to think I am capable - however, if you see that - then I'll put some trust there. I think my biggest stress is that my husband really puts stock into me being smart enough to do this by myself. I think he thinks I am smarter than I really am. He is extremely intimidated by it - so I said I'd learn it and plan it out. When we start to talk about it - I think that he expects me to have already have this all figured out - and it's taking time. An AIO feels so much easier I think - but with what you and @FilterGuy have said.... it seems absurd for me to do, especially with how much we'd really like to run already. I think I thought it was in the worksheet because I added it to my list of things to power and it was suggested by @MisterSandals I add 1900 watt hours per 24 hour period
1900Wh / 24h = 79W while running - to it - but I am not realizing that is JUST an inverter and wouldn't count as the AIO. ?‍♀️
 
Thank you for saying that - I am definitely willing and able to learn. I don't have the confidence to think I am capable - however, if you see that - then I'll put some trust there. I think my biggest stress is that my husband really puts stock into me being smart enough to do this by myself. I think he thinks I am smarter than I really am. He is extremely intimidated by it - so I said I'd learn it and plan it out. When we start to talk about it - I think that he expects me to have already have this all figured out - and it's taking time.
It should take time. Its a totally new area, that for most of us is not a very intuitive subject. A learning curve, and feeling overwhelmed is natural. And I totally understand the added stress of feeling like someone else is relying on you/expects that you know/have a handle on everything.

An AIO feels so much easier I think - but with what you and @FilterGuy have said.... it seems absurd for me to do, especially with how much we'd really like to run already.
An AIO is undoubtedly easier in some respects and some use-cases. BUT it can also be overstated, and imagined to be or presented as simpler than it is. One of Will's latest videos show's how dead simple an AIO can be in a certain use case. But its an extremely simplified example (and this is the case with most YT videos you will see), AC wiring, DC wiring, Shorepower, Grounding, and solar wiring are all ignored (outside of the scope of the video). Regardless of whether you go with an AIO or a separate Inverter/Charger and Solar Charge Controller, you will still need to address these areas.

So the main distinction is whether you have the (1) Inverter (2) Charger (3) MPPT Solar Charge Controller in a single device or split between two devices an inverter/charger and a solar charge controller. All in one saves on some wiring, and external complexities, but maybe not as much as imagined. I'm not saying that you shouldn't go with an AIO, just that you have a choice, where the difference in complexity may be less than you think (wiring a charge controller is pretty simple, and wiring an inverter/charger is about the same as wiring an AIO minus the solar input). If you can find an AIO with a low idle consumption, there is really no reason not to go with it, if it meets your needs, but you can design a reasonably simple system with separate inverter/charger and charge controller, which has its own advantages and probably disadvantages.

I should also note, I'm not an expert in anything, particularly not AIO's where I have very limited knowledge. So don't take anything I say as gospel, I'm just sharing my 2c.

I think I thought it was in the worksheet because I added it to my list of things to power and it was suggested by @MisterSandals I add 1900 watt hours per 24 hour period. 1900Wh / 24h = 79W while running - to it - but I am not realizing that is JUST an inverter and wouldn't count as the AIO. ?‍♀️
Oh, I may have misunderstood, if you have added 1900Wh for the inverter consumption, that would cover the whole AIO. I didn't realize/see that was included in the calcs. Sorry for throwing you off, sounds like you are on the right track. But if you do use two of them, you would double that number or double whatever number applies to the AIO or inverter you choose (assuming both are on 24/7).

On a separate note, if you've got @FilterGuy and @MisterSandals helping you out, you are in good hands, they are two of the most helpful people here on the forum. And the amount of helpful resources FilterGuy has created and made available on the forum is remarkable. I've helped him with a handful and know just how much time and effort goes into just one. Be sure to take advantage of the resources section of the website.
 
But if you do use two of them, you would double that number or double whatever number applies to the AIO or inverter you choose (assuming both are on 24/7).
Good catch!

I totally understand the added stress of feeling like someone else is relying on you/expects that you know/have a handle on everything.
Yeah... he doesn't feel like he can put up the walls or the ceiling in the bus because we have to do the wiring.
 
Yeah... he doesn't feel like he can put up the walls or the ceiling in the bus because we have to do the wiring.
I think *most* of the wiring should be the same regardless of whether you go with an AIO, discrete components, or two AIO's. I imagine that most or all of the wiring differences would be in the electrical closet/area (assuming your major components will be housed in the same area), and you will want this area to be accessible after the build is complete too. So spatially most differences should be constrained to the same area, and the wiring in the walls and ceiling would be pretty much the same one way or another I would imagine. But obviously, overlooking something or wiring something wrong and having to rip up a wall would be less than ideal.. so you are right to be concerned/cautious/want to work out the detail first.
 
I think I thought it was in the worksheet because I added it to my list of things to power and it was suggested by @MisterSandals I add 1900 watt hours per 24 hour period
I was just doing the math for @GLC post where he state that his AIO uses 1900 W (hours) per 24h period.

You need to look at the AIO that you are looking to buy for the idle consumption (and conversion efficiency) to see how much YOU should add to your energy calculations.


I have been following along and learning more than I have been contributing.
 
I think *most* of the wiring should be the same regardless of whether you go with...
Actually, I want to partially pull back from that statement. Considering that your options include 1 split phase AIO, 2 AIO's, or separate inverter/charger and charge controller, and at least a couple brands being considered, I dont want to be overconfident that the majority of wiring will be the same--though I still suspect it would be.
 
A couple of things:

1) Are you needing 240V?
2) Could you post the other part of the spread sheet so I can get a total picture?
 
The portable washing machine description says "use 120V 60GH"
How much water does the washing machine use?
 
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