What Voltage All-In-One Do I Need For Abundant Power Needs?

[roark12]

Hi everyone! First off, I apologize if posting this in the wrong place.

Admittedly, I am a total noob and am completely flustered over how big, and what kind of a system I need for a full-time, partially off-grid #vanlife system. I'm currently converting an ambulance into a camper which I'll be working out of. The only things I am sure of thus far are that I want an all-in-one system to conserve space...and more importantly, that I never have to conserve energy or ever worry about having enough power to live/work comfortably wherever I may be in North America.

But the more research I do, the more confused I'm becoming. And, unfortunately, adding to the complexity of my mostly off-grid build, I'm on somewhat of a restrictive budget.

I've been following Will's videos and this forum, as well as other online resources, but I'm still desperately needing guidance from any of you in the know who are willing to help me to configure the best system for my needs.

I am a musician and filmmaker. In addition to needing to keep professional camera gear charged, I'm needing to run a small audio/video production/post-production studio from wherever I may be. Consequently, I'll be running a considerable amount of 120v gear--guitar amps, audio interfaces, mics, studio monitors, synthesizers, outboard effects, power conditioners, etc., and a power-hungry Mac system with multiple external drives. I also have a rather large 12v fridge and am presently hunting for the best-suited 9000BTU mini-spit to absolutely keep everything (including myself) cool and warm as needed.

I've already bought and received 4x208AH 12v batteries (which Will recommended), am awaiting delivery of 4 super-efficient 475w bifacial panels, and was about to pull the trigger on an MPP6548 to run it all. Other than space savings, I'm going with an all-in-one unit, again, on Will's advice, for beginners wanting a plug-and-play easy install. I'm also wanting this system to run directly to load when ample sun is available, and have already been advised I'll need at least a 6000w+ inverter to run all my gear...leaving me very limited options aside from a 48v system...assuming I'm understanding the vast amount of new (to me) information correctly.

I'm also afraid I may have already messed up by buying 12v batteries and what I believe to be 12v panels. Assuming that I'll now have to run the 4 panels and my 4 12v batteries in series to accommodate a 48v all-in-one, I worry about shading problems and having to always be parked in direct sun to meet my power needs. Or if I'm even needing such a large 48v unit at all. I possibly still have a little time to cancel these panels and swap them out for higher voltage units if deemed a better fit for my needs, on your generous recommendations.

Any helpful advice this forum can offer would be HUGELY appreciated. I really don't know how to proceed.

Thanks in advance,
Kevin

 

[mopat]

what panels are they?
Eagle 78TR G4b | 475W 78 Half-Cell Mono Bifacial 1500V Solar Panel, JKM475M-7RL3-TV ??

need panel specs, Voc =?

 

[jimcalf]

If you really need that much power, you may also benefit from a 2nd alternator to charge your batteries, and a larger 48v battery system. Adding 12 more cells would be the easy way to hit 48v. Any estimate on the daily energy requirement? I used my Hughes Watchdog surge protector to monitor my shore power usage over several weeks to really understand my usage and built to specifically accommodate that. It was a really cheap way to monitor a 30A 120V connection. If you're driving daily, you'll be surprised how much power a high quality Balmar type alternator can produce. Since you're converting an ambulance, it may already have a 2nd alternator. That's normally how ambulances support their own high energy demands.

 

[roark12]

what panels are they?
Eagle 78TR G4b | 475W 78 Half-Cell Mono Bifacial 1500V Solar Panel, JKM475M-7RL3-TV ??

need panel specs, Voc =?

Thanks for the reply! Yes, the Eagles. Driving now though, I'll get back with panel specs once home.

 

[mopat]

The open circuit voltage (Voc) for those panels is 52.16V and the LV6548 inverter can handle up to 250V.

You should be able to connect the 4 panels in series. 4 x 52.16 =208.64 < 250, good.

 

[roark12]

The open circuit voltage (Voc) for those panels is 52.16V and the LV6548 inverter can handle up to 250V.

You should be able to connect the 4 panels in series. 4 x 52.16 =208.64 < 250, good.

Thanks! What if I was to go with a 24v all-in-one system instead? And if connecting the 4 panels in series, wouldn't all panels drop in efficiency if any of them were in the shade?
Thanks again for your help!

 

[Dzl]

If you really need that much power, you may also benefit from a 2nd alternator to charge your batteries, and a larger 48v battery system. Adding 12 more cells would be the easy way to hit 48v.

I believe they have 4 x 12V batteries (not 4 cells @ 12v combined).

 

[Dzl]

I'm also afraid I may have already messed up by buying 12v batteries and what I believe to be 12v panels.

Your panels are not '12v' no large panels are. Buy beyond that, talking about panels as "12v" "24V" etc is a hangover from the pre-MPPT days, its not really very relevant anymore. Your panels will be compatible with any common battery bank voltage. With your desired controller your probable choices would be 4 in series (4S) or 2 parallel strings of 2 in series (2S2P).

If you really need a 6000W inverter, I would strongly consider 48V if the batteries you purchased can be configured in that way. 6000W = a lot of current at anything other than 48V+, its not completely out of the question but its very far from optimal.

 

[mopat]

What if I was to go with a 24v all-in-one system instead

I'll need at least a 6000w+ inverter to run all my gea

+6000 watts on 24 volts = mistake

 

[Jerrys13]

+6000 watts on 24 volts = mistake

250 AMPS vs 125 AMPS = No biggie. Especially for Mobile applications.... I have an ambulance and am doing that very thing. (2) Growatt 3000 in split phase for 120 and 240 needs. EG4 series 3 24v 5.1KW 200AH x 6 = 30KW limited to 3000 watts 120v per side or 6000 240. Soooo completely doable. All U.S. Military vehicles are 24V or a 12v/24V combo pushing over 400AMPS out of their generators and are SLA.

If you want to run large panels you can (Ambos support their weight and structural integrity better than all other vehicles because they actually perform rollover tests with them) If your out west in the summer 9000BTU will Barely get you by. I'm going 12,000BTU because you can get good SEER ratings at 120V anything above 22 seer and your looking at 240V. Watch the Youtube vids on Mini-splits and pay attention to the draw. It's usually 150 - 500 watts nominal. When you insulate your box retains temp, thermal bridging and heat induction are going to be an absolute pain. Also 12000 BTU does a better job of dehumidifying which will keep mold out. Since you will be running 24V you can use military inter connects like "Slave Cables" and HWMMV shunts which are cheap on the web.

 

[Jerrys13]

Hi everyone! First off, I apologize if posting this in the wrong place.

Admittedly, I am a total noob and am completely flustered over how big, and what kind of a system I need for a full-time, partially off-grid #vanlife system. I'm currently converting an ambulance into a camper which I'll be working out of. The only things I am sure of thus far are that I want an all-in-one system to conserve space...and more importantly, that I never have to conserve energy or ever worry about having enough power to live/work comfortably wherever I may be in North America.

But the more research I do, the more confused I'm becoming. And, unfortunately, adding to the complexity of my mostly off-grid build, I'm on somewhat of a restrictive budget.

I've been following Will's videos and this forum, as well as other online resources, but I'm still desperately needing guidance from any of you in the know who are willing to help me to configure the best system for my needs.

I am a musician and filmmaker. In addition to needing to keep professional camera gear charged, I'm needing to run a small audio/video production/post-production studio from wherever I may be. Consequently, I'll be running a considerable amount of 120v gear--guitar amps, audio interfaces, mics, studio monitors, synthesizers, outboard effects, power conditioners, etc., and a power-hungry Mac system with multiple external drives. I also have a rather large 12v fridge and am presently hunting for the best-suited 9000BTU mini-spit to absolutely keep everything (including myself) cool and warm as needed.

I've already bought and received 4x208AH 12v batteries (which Will recommended), am awaiting delivery of 4 super-efficient 475w bifacial panels, and was about to pull the trigger on an MPP6548 to run it all. Other than space savings, I'm going with an all-in-one unit, again, on Will's advice, for beginners wanting a plug-and-play easy install. I'm also wanting this system to run directly to load when ample sun is available, and have already been advised I'll need at least a 6000w+ inverter to run all my gear...leaving me very limited options aside from a 48v system...assuming I'm understanding the vast amount of new (to me) information correctly.

I'm also afraid I may have already messed up by buying 12v batteries and what I believe to be 12v panels. Assuming that I'll now have to run the 4 panels and my 4 12v batteries in series to accommodate a 48v all-in-one, I worry about shading problems and having to always be parked in direct sun to meet my power needs. Or if I'm even needing such a large 48v unit at all. I possibly still have a little time to cancel these panels and swap them out for higher voltage units if deemed a better fit for my needs, on your generous recommendations.

Any helpful advice this forum can offer would be HUGELY appreciated. I really don't know how to proceed.

Thanks in advance,
Kevin

I'm not sure if anyone else caught this but the gear your running is highly sensitive to "Noise" that High Frequency inverters put out. It would be more weight, but a Low Frequency inverter will not have as much sensitivity issues with your equipment when running an LF inverter. I went cheap with the Growatts and now have to ferrite everything for my ham radio equipment.

 

[Dzl]

250 AMPS vs 125 AMPS = No biggie.

Should be closer to 300-330A once inverter inefficiency is accounted for (not including any surge, but if its an HF inverter, surge is not really a real factor).

 

[eXodus]

(2) Growatt 3000 in split phase for 120 and 240 needs. EG4 series 3 24v 5.1KW 200AH x 6 = 30KW limited to 3000 watts 120v per side or 6000 240. Soooo completely doable. All U.S. Military vehicles are 24V or a 12v/24V combo pushing over 400AMPS out of their generators and are SLA.

2x 3000w is not the same as one 6000w

you are using two sets of battery cables so you technically don't have more then 125A going to each Growatt.

Yes you got 250A current going over one busbar - but at every other point of your system you have far less than that.
Which is a good design by the way.

I wouldn't not want to have close to 150A to a single component in a mobile system. That's why over 3000W most people are going to 48V - which is good practice. Or like you did - take two units.

 

[Jerrys13]

2x 3000w is not the same as one 6000w

you are using two sets of battery cables so you technically don't have more then 125A going to each Growatt.

Yes you got 250A current going over one busbar - but at every other point of your system you have far less than that.
Which is a good design by the way.

I wouldn't not want to have close to 150A to a single component in a mobile system. That's why over 3000W most people are going to 48V - which is good practice. Or like you did - take two units.

Thanks eX. That's a good point about the division of amperage between the 2 units vs his single all in one system. My main loads with the most run time are 24v contingent,
1) I intend to keep all the exterior box lights and switch them to LED which run most efficiently at 24V with a .9A draw x 15 exterior and 12 Lights interior.
2)The ICECO fridge will run 24 /7 @ 24v will be a 1.6A draw vs 3.7 @ 12V.
3) The interconnect between the tow behind electric car will be 24V as back up battery to the rig (240V is to charge the tow behind with power generated from the rig)
4) My home back up batteries are on the rig so they need to connect to the AC coupler when the lights go out. A 24V Military Slave Cable configuration allows me to do that. Who knows... maybe even help jumpstart a Military vehicle stranded on the side of the road.

So my use case is different than roark12's which requires a heavy 120V demand so I understand why 48V would make more sense in terms of keeping amperage down and running loads for a longer time with better efficiency. Thanks for your input it's always appreciated.

 

[MattiFin]

With the power requirements you have and desire to operate anywhere in northern America you are looking for a good generator assisted with solar…

 

[roark12]

thank you for the reply. I want to stealth camp in neighborhoods and can’t run a generator. That’s why I was buying such high wattage panels and 800 amp hour of battery. But I still can’t figure out if I need a 48 V system or a 24 V system if you have any input on this it would be appreciated

 

[roark12]

I'm not sure if anyone else caught this but the gear your running is highly sensitive to "Noise" that High Frequency inverters put out. It would be more weight, but a Low Frequency inverter will not have as much sensitivity issues with your equipment when running an LF inverter. I went cheap with the Growatts and now have to ferrite everything for my ham radio equipment.

Wow, thanks. I never even considered the noise affecting my recording equipment. How dumb of me. So I guess it would be better to go with a 24V all in one with a 5000w inverted.instead of the 48v. Would you say that that’s right? But if so, how would I wire 4x200ah batteriea and 4 panels into a 24 V system?

 

[roark12]

2x 3000w is not the same as one 6000w

you are using two sets of battery cables so you technically don't have more then 125A going to each Growatt.

Yes you got 250A current going over one busbar - but at every other point of your system you have far less than that.
Which is a good design by the way.

I wouldn't not want to have close to 150A to a single component in a mobile system. That's why over 3000W most people are going to 48V - which is good practice. Or like you did - take two units.

Thanks for the reply. I was looking at the dimensions of most 48V systems and have no idea where it will fit in my ambulance. But if you’re correct, it sounds like I have to find a place for the 48 V. I need a high surge wattage for my gear, my 120 V refrigerator and 120 V mini split AC/heater. How would that work out with four panels and for 200ah batteries?

 

[Dzl]

One thing to be aware of with the All-in-ones, they are known for pretty substantial idle power consumption/inefficiency, at least they were last I heard which was maybe a year ago. What this means in a space limited mobile build is that a not insignificant amount of your PV will go to just feeding the inverters idle power draw. I suggest looking into this before pulling the trigger, I believe will had a video a year or two back discussing this, not sure if anything has changed.

I also suggest doing a good solid accounting of the high draw devices you will use (a so called 'energy audit') how much power they draw and how many hours a day you will need to use them, that should help direct inverter choice and battery bank voltage (and give you an idea whether your goals are realistic given the constraints of a vehicle).

This specifically, is usually an unrealistic expectation when it comes to space limited off-grid solar:

The only things I am sure of thus far are that I want an all-in-one system to conserve space...and more importantly, that I never have to conserve energy or ever worry about having enough power to live/work comfortably wherever I may be

 

[Dzl]

Wow, thanks. I never even considered the noise affecting my recording equipment. How dumb of me. So I guess it would be better to go with a 24V all in one with a 5000w inverted.instead of the 48v. Would you say that that’s right? But if so, how would I wire 4x200ah batteriea and 4 panels into a 24 V system?

No, when they refer to high and low frequency inverters they are not referring to voltage, they are referring to the type of inverter/how it is designed.