Van build - setup design check?

[atelierminceur]

So i'm building a ford transit custom and i'm pre planning the electrical system to see how much it would cost and if it would be sufficient.
The build is temporary i'm not sure yet of 3 main elements (Inverter, DC/DC, battery size)



1. Use case
Max 1 week at a time to basically to go climbing remotely. I would like to be sufficient in energy for max 2-3 days without driving.

2. What i will be running power wise
Maximum : 70 Ah on the 220v AC and 15 Ah on the 12v dc so a total of 85Ah per day (per my calculations)
A small 100l fridge on the AC at around 30 Ah, an induction cooking and an instantpot with around 35Ah per day max if i cook 2x (more or less need help see questions)

3. How do i plan to charge the battery
- Pre charge it at home with shore
- 2 Solar panels in either parallel or serie
- DC to DC charger
- An EV charging port like this (Does this make sense?)

Here is a list of the components of the system:

Solar panels:
2x Victron 175w solar panels

The solar charge controller is the "SRNE LC2430N10H"
- max input power is 400w on 12v
- 30A with a max load & load power of 100w

Battery is Litime 12v 230 Ah plus
-LifePO4
- 200A BMS that can support 2560w load power

or

Battery is Litime 12v 300 Ah
-LifePO4
- 200A BMS that can support 2560w load power

Dc to DC Battery charger is LiTime 12V 40A DC To DC
Providing 40a of dc charging from the battery to be able to charge while driving

Modular DC busbar is the Lynx Distributor from Victron
Basically just a simple but nice fuse holder

Inverter/Charger is SRNE RVI1230S100
- 220v 12v
- 3000w of rated output but 6 VA of peak
- 100A of generator charging current
- <4A at 12.5v in no load consumption
- >92% efficient
- 7.5kg which is kinda heavy but ok i mean inverter weight
- <60db fan at max which is high but i should have a huge margin

The few questions i have:
1. Does my system make sense how i've planned for my use case ? what would be the shortcomings?
2. Why does the 2 batteries 300Ah and 230Ah have the same max load power ? The only real differences are in the capacity basically it seems. The 300Ah is even cheaper somehow. Is the 230Ah enough for my setup since they are both so similar beside capacity
3. With my inverter going at 3000w am i fine with that battery or do i risk a problem running that high an amperage on it with it being a 12v system. Considering that 3000w w the 12v system is like around 250A ?
3.2 is the margin on the inverter good to be sure it wont run like hell ?
4. The ford transit custom i'm converting has an alternator which seems to be rated for 150a so divided by 2 i could actually run a 75A DC/DC charger but i cannot seem to find any. Is it overkill to do so ? Why dont they seems to be around ? Maybe i should upgrade to 60a DC/DC
5. Can i have all of thoses units in the same square ventilated box basically to limit the wire length ? People often say their wire are huge but i don't get why in a van..
6. the ev charging port that i added higher, is it a hazard or not advised to use thoses?
7. I was hesitating going with a smaller inverter from SRNE the SRNE SR-LC-12-3k but i like that the SRNE RVI1230U100 on my diagram can go at 6000VA and basically can be connected to the grid directly so no need for another AC/DC charger..

Last question finally: how can i know precisely without measuring how much would an induction cooktop cost of Ah per day if i run it for 30mn at setting 4 out of 9.
So far i've used lots of online post to eyeball it and its the same with the instantpot and the fridge but i'm not sure how i can know because it depend all on specifics of a model right? So i would basically need to run the fridge and the other appliance for a day to see irl data?

Thanks for reading if you went that far haha

 

[scrubjaysnest]

First do an energy audit of your uses. This determines battery bank size. From there you get solar required. It's a pita I know has to be done for best chance of success.

 

[atelierminceur]

First do an energy audit of your uses. This determines battery bank size. From there you get solar required. It's a pita I know has to be done for best chance of success.

Ive said i did in an excel sheet if you read my message its 85Ah

 

[MisterSandals]

Maximum : 70 Ah on the 220v AC and 15 Ah on the 12v dc so a total of 85Ah per day (per my calculations)

85Ah x 12.8V = 1088Wh

300Ah x 12.8V = 3840Wh capacity

Last question finally: how can i know precisely without measuring how much would an induction cooktop cost of Ah per day if i run it for 30mn at setting 4 out of 9.

True Induction TI-1SS Protable UL197 Certified, 13-inch Comercial Single Induction Cooktop 3500W Glass-Ceramic Top

The Commercial True Induction series induction cooktop with 3500 watt gives you the same great portability and efficiency of our home use single induction cookers but with the control and power of a commercial range.

www.trueinduction.com

I dunno, this says 3500W
If you cook/boil something at half power, it should take twice as long so Wh should total energy should be similar.

3500W x .5h = 1750Wh per day (about half your battery)

Factor in your inverter standby power (?60W?)
60W x 24h = 1440Wh per day (37% of your battery)
For intermittent use, maybe a stand alone inverter you could power off when not in use would refuse idle power waste.

I am not seeing how this could last a single day even without the fridge.

The 2 solar panels and a lot of sun will be critical. A stand-alone Victron 100/30 would be cheap and easy.

The ford transit custom i'm converting has an alternator which seems to be rated for 150a so divided by 2 i could actually run a 75A DC/DC charger but i cannot seem to find any. Is it overkill to do so ? Why dont they seems to be around ? Maybe i should upgrade to 60a DC/DC

I have installed these and a 30A Victron Orion is a lot for a stock Transit. Is there an electrical access point in the cargo area (maybe in passenger side door pillar)?

 

[atelierminceur]

85Ah x 12.8V = 1088Wh

300Ah x 12.8V = 3840Wh capacity

True Induction TI-1SS Protable UL197 Certified, 13-inch Comercial Single Induction Cooktop 3500W Glass-Ceramic Top

The Commercial True Induction series induction cooktop with 3500 watt gives you the same great portability and efficiency of our home use single induction cookers but with the control and power of a commercial range.

www.trueinduction.com

I dunno, this says 3500W
If you cook/boil something at half power, it should take twice as long so Wh should total energy should be similar.

3500W x .5h = 1750Wh per day (about half your battery)

Factor in your inverter standby power (?60W?)
60W x 24h = 1440Wh per day (37% of your battery)
For intermittent use, maybe a stand alone inverter you could power off when not in use would refuse idle power waste.

I am not seeing how this could last a single day even without the fridge.

The 2 solar panels and a lot of sun will be critical. A stand-alone Victron 100/30 would be cheap and easy.


I have installed these and a 30A Victron Orion is a lot for a stock Transit. Is there an electrical access point in the cargo area (maybe in passenger side door pillar)?

Nah the induction cooker i've found is 2000w and basically surge on/off every x sec and you usually cook on medium setting max for most use so its 1000wx0.5h = 500Wh per day maybe 750Wh

The inverter standby power is per manual but not sure its true "No-Load Consumption: Battery current<4.0A@12.5V" and
"Energy-Saving Consumption: Battery current<1.0A@12.5V" which i just highly doubt since most inverter this size are around 50w when idling. But surely the energy saving mode is lower than that ?

If its the case that its sucking 1440wh per day just idling yeah surely i would need to get a bigger battery or either just ditch the 230v fridge so i can shut the inverter on/off only when needed.. But ive seen many videos of vans with a fridge and their system work out with a pretty similar setup so not sure whats wrong? Arent there inverters which idle well and wouldnt consume that much during the day ? Some of the victron one seems to idle around 20w.

 

[MisterSandals]

Nah the induction cooker i've found is 2000w

Ok, it’s up to you to figure it out, either on paper or in use.
If you can find a 12V fridge it may help. Personally I love propane powered fridges.
Some inverters idle lower than others but you pay for that with better equipment.

My successful solutions involve good equipment, lots of battery and as much solar as I have room for.

The math doesn’t lie, well never in your favor anyway.

 

[HarryN]

Strongly consider to build it as a 24 volt system instead of 12 volt.

I am not sure about Europe - in the US we cannot count on camp sites to always be wired correctly, so I always suggest to use a separate AC charger and inverter vs a combo unit.

If you want a really solid, reliable power system, look at the max discharge rating of your desired battery and run it at 50-60% when powering the inverter at your maximum desired rate. Often this means more, smaller capacity batteries vs one larger one.

Think of your battery kind of like a bottle of beer. Just because one bottle of beer is larger than another, that does not mean that you can pour it out any faster. Two smaller bottles of beer pouring out will often result in a faster ability to pour beer than just one due to the opening size.

If you try to pour beer out of a bottle at the absolute max capability, the flow can go unstable. If you are pouring it out at 50% of the max, it will behave in a more stable way and be more tolerant of glitches. More or less, the same is true of batteries.

It is an easy thing to test at home and visualize using the beer analogy.

 

[HarryN]

Vehicle Mounted Systems

RV's, Vans, Trucks and More! Typically 12v, and 100-1000w, but the limits are endless!

diysolarforum.com

Here is some info on mobile power systems that might be useful.

As far as the solar, you should go to at least three of those panels right away instead of two, might even need 4 of them for your loads if running an inverter to power a fridge. Even with a DC fridge, 2 would be marginal, especially with a small battery pack like that.

If you have the 148 WB Transit, should be able to get 4 of them on the roof.

 

[Rocketman]

A couple of items I think you need that are missing and some things to consider.

A good shunt based battery monitor - Victron Smartshunt or BMV712. You need to know exactly the state of charge (SOC) in the battery. The issues with many of the ones in the bms is they don’t count small current flows in and out very well.

Also, going to your 12v fuse box, I would install a Victron smart battery protect (BP65). This will protect the battery if you happen to leave a 12v item on. It shuts down at ____v (user setable- say 12.0v) and restarts at _____v (say 12.5v). This way you prevent to bms from shutting down in low SOC situations. Some bms’s are difficult to restart if they get to low critical stage. It can also be used as a on/off switch- so you may be able to delete the on/off switch on that leg.

I don’t know the European Victron inverter chargers, but the American one I have is very low standby watt useage and highly efficient.

Do use an inverter/charger that connects directly to the grid. It is great!

Good Luck!

 

[atelierminceur]

Vehicle Mounted Systems

RV's, Vans, Trucks and More! Typically 12v, and 100-1000w, but the limits are endless!

diysolarforum.com

Here is some info on mobile power systems that might be useful.

As far as the solar, you should go to at least three of those panels right away instead of two, might even need 4 of them for your loads if running an inverter to power a fridge. Even with a DC fridge, 2 would be marginal, especially with a small battery pack like that.

If you have the 148 WB Transit, should be able to get 4 of them on the roof.

Thanks for the link. No the transit custom is the smallest one short wheelbase low roof and its only for climbing trips so.
Two is more or less the maximal amount i can put on the roof with a maxxair fan..
Is 300Ah really a small battery for a van lol ?

 

[atelierminceur]

A couple of items I think you need that are missing and some things to consider.

A good shunt based battery monitor - Victron Smartshunt or BMV712. You need to know exactly the state of charge (SOC) in the battery. The issues with many of the ones in the bms is they don’t count small current flows in and out very well.

Also, going to your 12v fuse box, I would install a Victron smart battery protect (BP65). This will protect the battery if you happen to leave a 12v item on. It shuts down at ____v (user setable- say 12.0v) and restarts at _____v (say 12.5v). This way you prevent to bms from shutting down in low SOC situations. Some bms’s are difficult to restart if they get to low critical stage. It can also be used as a on/off switch- so you may be able to delete the on/off switch on that leg.

Thanks i'll check them out seems like good additions and not so expensive too

I don’t know the European Victron inverter chargers, but the American one I have is very low standby watt useage and highly efficient.

Yeah what i see indicate that they basically idle low around 20w which is pretty decent at around 480Wh per day

Do use an inverter/charger that connects directly to the grid. It is great!

Isnt it problematic for the reason the other poster added that if there is a damage because of poor shore installation the whole combo will basically get damaged ? Seems uncommon in europe i havent read about it but ..

 

[atelierminceur]

Strongly consider to build it as a 24 volt system instead of 12 volt.

Yeah but it seemed overkill for my small system and most of the units in the chain are only available in 12v.. and the gains seems marginal or im missing something ?

I am not sure about Europe - in the US we cannot count on camp sites to always be wired correctly, so I always suggest to use a separate AC charger and inverter vs a combo unit.

I havent heard of this problem in europe but it's scary enough to investigate if its common in eu..

If you want a really solid, reliable power system, look at the max discharge rating of your desired battery and run it at 50-60% when powering the inverter at your maximum desired rate. Often this means more, smaller capacity batteries vs one larger one.

Yeah sadly i dont have any of the components since i'm just planing them so if i could test them i would know. I just know the max discharge current of this battery is 200a which seems fine to me ? but maybe i'm missing something ?

Think of your battery kind of like a bottle of beer. Just because one bottle of beer is larger than another, that does not mean that you can pour it out any faster. Two smaller bottles of beer pouring out will often result in a faster ability to pour beer than just one due to the opening size.

If you try to pour beer out of a bottle at the absolute max capability, the flow can go unstable. If you are pouring it out at 50% of the max, it will behave in a more stable way and be more tolerant of glitches. More or less, the same is true of batteries.

It is an easy thing to test at home and visualize using the beer analogy.

Yeah but then what if i have 3x100 what do i gain beside a more stable flow which i dont see being that important since i'm only running a few items at a time on both 12v and AC

 

[HarryN]

Most anything for vans that is available for 12 volt DC is also available in 24 volt DC or as a dual 12 / 24 volt.

Just look at the battery supplier's data sheet to obtain their official max output amps rating and use it at 50-60%. Similar to your van's engine, you don't use it at 100% of the torque or hp or it will break fairly quickly.

You have a 2 000 watt load, that is really 24 volt territory. Anytime that you end up with a wire in a van that has > 100 amps going through it, it is time to consider to raise the voltage.

 

[atelierminceur]

Most anything for vans that is available for 12 volt DC is also available in 24 volt DC or as a dual 12 / 24 volt.

Just look at the battery supplier's data sheet to obtain their official max output amps rating and use it at 50-60%. Similar to your van's engine, you don't use it at 100% of the torque or hp or it will break fairly quickly.

You have a 2 000 watt load, that is really 24 volt territory. Anytime that you end up with a wire in a van that has > 100 amps going through it, it is time to consider to raise the voltage.

On 24v everything is around twice the price.. Can't i just get huge wires and be ok with it ? Why would i need to upgrade i've seen plenty of build with 12v and 3000w inverters in their van

 

[HarryN]

On 24v everything is around twice the price.. Can't i just get huge wires and be ok with it ? Why would i need to upgrade i've seen plenty of build with 12v and 3000w inverters in their van

In general, we don't have that experience in the US for the same quality of part.

It might be that the 24 volt parts (such as a breaker ) are marine grade which are more vibration resistant and the parts are tin plated for corrosion resistance vs just bare copper.

In the US, a 12 volt DC refrigerator is the same price as a 24 volt or dual 12 / 24.

LED light strips are the same price for 12 vs 24.

A fuel heater that runs on 12 vs 24 is more or less the same.

Inverters that are 12 volt in are the same as 24 volt on line.

DC - DC converters that are 12 - 12 volt are the same price as 12 - 24 volt from for instance sterling.

A terminal block / bus bar price will mostly be rated on current flow. If you need it to run 300 amps, they way that they are built you will really need a 500 - 600 amp version to be in spec if that matters to you.

Here is an example company that makes common DC components that are rated for 12 or 24 volt.

Fuse Blocks - Blue Sea Systems

Engineering high quality marine electrical components for safety, reliability and performance

www.bluesea.com

_____________-

The place where running 12 volts into a 3 000 watt inverter becomes problematic is in the fusing and breakers.

A 300 amp breaker that will actually run at that current reliably is a really expensive breaker. All of the consumer item level 300 amp breakers that I have tried were junk and would not operate.

____________

What are you wanting to purchase that a 24 volt version is more than the equivalent quality 12 volt item?

 

[atelierminceur]

I mean am i wrong to think that its still beneficial to get an inverter but maybe a better one like the victron multiplus which consume 20w or so at idle (depending if i get a good one..) rather than get a 12v fridge like the dometic one's which apparently on many websites people have them consuming close to 80-100Ah per day on 12v.. while i still have to maybe power the inverter 1hr a day or so..

 

[atelierminceur]

The place where running 12 volts into a 3 000 watt inverter becomes problematic is in the fusing and breakers.

A 300 amp breaker that will actually run at that current reliably is a really expensive breaker. All of the consumer item level 300 amp breakers that I have tried were junk and would not operate.

Yeah ive tried looking for 300a breaker and i cannot find more than 275a breaker at like 100-150€.
But even if i get a DC fridge i still have to run the AC stuff on an inverter that will see high currents while its feeding the appliance and if im converting 24v to 12v with a dc/dc im still losing some efficiency in the process so i'm sure i won't save battery. And almost everything i have on DC is 12v so far.

And heck even in my case all the electrical components will be a few cm away so it's not like i'm buying long cables. Everything will be pretty short/efficient

i was looking at this article mostly

12V vs 24V vs 48V Van Electrical System | Which Is Best for YOU?

Benefits, drawbacks, real-world COST ANALYSIS of 12V vs 24V for small/medium/large electrical systems. No, 24V is not significantly cheaper!

faroutride.com

____________

What are you wanting to purchase that a 24 volt version is more than the equivalent quality 12 volt item?

the litime battery is more expensive at 24v for ex

 

[HarryN]

I mean am i wrong to think that its still beneficial to get an inverter but maybe a better one like the victron multiplus which consume 20w or so at idle (depending if i get a good one..) rather than get a 12v fridge like the dometic one's which apparently on many websites people have them consuming close to 80-100Ah per day on 12v.. while i still have to maybe power the inverter 1hr a day or so..

Here is a recent discussion on the forum about refrigerators for applications like you have.

Fridge advice and guidance.

My Norcold has turned into a Nevercold :( . I'm looking primarily at the conversion kit to add a compressor kit to my existing fridge. Second choice may be replacing the whole fridge with a RV specific 12v compressor fridge. Third choice might be a residential fridge. I'm leaning to 12v over...

diysolarforum.com

________

To some extent, this can be a region based decision. In the US, the common home, 120 vac refrigerator, on average uses ~ 2 - 2.5 kW-hr per day over the course of a year. (according to the energy label). My simplistic testing results were similar. The really nice thing is that they have automatic defrost and this keeps them running at a fairly efficient level while maintaining the space.

Some of the larger RVs sold in the US also use this type of refrigerator and it is very tempting for me as well.

One of my friends has a Ford Transit and I helped her with her electrical system. The single biggest challenge that she has is ice build up in the refrigerator door, causing it to open slightly and leak. Her fridge is a dual DC unit and of course this ruins the entire efficiency of the concept.

In order to clean out the ice, she has to completely empty it, defrost, etc which is not very convenient and kind of takes us back to the 1950s when it comes to refrigeration convenience.

________

I have spent a total of perhaps 6 weeks in Europe on business trips and looked at the refrigerators there. I remember that they were quite a bit smaller but also tended to be fairly efficient so the difference might not be all that different vs a 12 / 24 volt model.

_________________

I like to have these types of systems setup so that solar can keep the refrigerator going even if the van is not driven.

The advantage that you have now vs in the past, is that EV chargers are more common, so if you have enough battery pack capacity, you can use those to supplement more easily.

 

[HarryN]

I don't have any personal experience with that battery brand.

In general you can put two batteries in series to make a 24 volt battery pack.

If a battery is not rated to do this, then I would not personally use it as it likely has other limits. Some brands shut off all power in and out at roughly freezing, while others still allow discharge but not charging.

You had mentioned that you didn't own any 12 volt items yet, so I assumed that you were starting from scratch.

I used DC - DC converters to help with the few items that need them.

Van electrical systems are a series of trade offs. It can become almost philosophical as the cost is often very similar.

_________--

Technically, a 12 - 24 volt DC - DC charger will be more efficient than a 12 - 12 volt version.

The reason is that the 12 - 24 volt one can use a single circuit that very efficiently "boosts" the voltage.

The 12 - 12 has a more complex circuit that will sometimes "boost" and sometimes reduce / "buck" the voltage and usually these are not as efficient.

Again - you are in shooting range of the path that works for you. A forum like this is just people who have done it a wide variety of ways and are throwing in our opinions / experiences. Ultimately it all has to work for you and your comfort level.

____________

I have nothing against far out ride, but it isn't always correct either.

Personally I look at the voltage question in a different way. If you had a 6 volt system like people used around 1910, would you switch to a higher voltage the next time you build something? Probably yes.

If you have a 24 volt system now, would you switch to a 12 volt system on your next build? Probably not.

 

[HarryN]

Some of this comes down to how often you will be driving. My vehicle does not move as much / as far as a lot of other people.

With a smaller van like you have, there just is not all that much room on top for solar, so you will need to make up for this with a larger battery pack and finding ways to charge it more often. This will be true no matter what path you choose for refrigeration, DC or AC as that set of panels will not run it in overcast conditions.

I have only been in Geneva for a few days and it was a long time ago. Very nice place. Unfortunately I was stuck in meetings nearly the entire time so I only saw it at night, so I don't know if the elevation helps to produce clear skies and strong sunlight or not.