My DIY Van Solar Setup - 450 W Panel - 'Need a little help

[Marmatth]

I'm a newbie at getting my solar system together. Any help would be greatly appreciated. My solar panel is 450 W. The main item I want to keep running without interruption is my fridge (Explorer Bear 50L 12/24V) stated energy consumption: 2.8AH/H Ambient @77F, Internal@0F. See my image for the other items I want to occasionally power. I'm anticipating I will need two batteries. I am unsure of the size - also possible company to buy from with an affordable price for a quality battery. I don't think I'll get an AC converter and will probably get a power station. What is the least expensive and 'smallest' power station that might work? I also heard that the power station can 'charge' the batteries and at some point the batteries can 'charge' the power station. How does this work? What cables should I purchase? I already have the one from the panel to the charge controller.

 

[Marmatth]

I'm hoping one day to offer assistance to others. I don't mean to be so 'needy' with all my questions. The rep at the solar shop was not helpful at all. I figure the batteries are really important. I live in AZ so will most probably stress the system with heat. I'm installing computer fans to help reduce some of the heat. I might be somewhere cold at times and I see that some of the batteries have some type of protection from freezing weather. Thank you in advance for any help. Also, I am hoping to buy something prior to things getting crazy with the tariffs.

 

[wme]

More questions than I can answer at this late hour. But it seems that you have duplicated your power.
1. Solar panel to charge controller to batteries to 12v load, all good.
2. Solar panel direct to Bluetti to 12v load AND also a 120v AC power source for "stuff.
I don't think you need both.
Better answers in the morning with fresh coffee.

 

[Marmatth]

Thanks for your help with this build. I thought that using the solar to power up the portable power station along with one or two auxiliary batteries would give the system enough storage. I might have written something in a confusing way in the illustration, but I did not mean that I was adding an AC power source for the additional stuff. The power would come from the portable power station and batteries. I hope that helps. I'm looking at an Ecoflow 1800W AC/100W USB-C output power station. I believe it has a hookup for the auxiliary batteries. Does this make sense?

Also, the solar panel can't go direct to the Bluetti (or whichever power station I purchase) as there's too much wattage. The charge controller must be set up between the solar panels and the Bluetti.

Any additional help would be greatly appreciated.

 

[Marmatth]

What size batteries is the big question along with what company might be good. Also, do I need two batteries along with the power station?

 

[740GLE]

I there a reason your looking to have a portable power station as well as dedicated solar/battery system?

Is it just for the included inverter and portability?

What equipment do you currently own? Sounds like the fridge and a single 450w solar panel?

The fridge can run on 24v? If so id start with a 24v system and plan around that it’d have the best future proof.

As for maths that 2.8ah/h is best calculated in Whr. I’m assuming 2.8ah is at 12v, so

2.8*12=33.6whr

Now 33.6whr*24hrs = 806whr/day

toss in the fact you are opening up the fridge some of the time and cooling stuff down so round up to 1kwhr/day.

If you plan your battery around not having any PV generation for 3 days that’s 3kwhr of just fridge usage.

So at 24v if you have 200ah of battery storage you’re at 4.8kwhr. A good start for a van build.

Check out ecoworthy 24v batteries 100ah units, aren’t terribly expensive. You can start with one and add another if you see your usage needing it.

 

[wme]

I still think you are doubling up on the wrong things,
What exactly do you have, brand and model number of each.
You can buy extra batteries for solar generators, but they are brand specific (more$$$).
If you PROMISE you won't want 120v AC then a more basic system would do nicely in a van. Solar panel, SCC, battery and a 12v/usb power panel.
A deluxe version would add a voltage shunt and a DC to DC charger.
Battery prices are nuts now, but a pair of 24v 100ah batteries would do a lot to future proof your setup.

 

[Marmatth]

Hi Solar Wizard! Thank you for all your comments and questions. You know, I don't have a lot of cash for this project and they guy helping me out at the solar place (I think lazily) suggested that I buy a PPS that would be capable enough to handle the system and then add one battery. Not that I'm that knowledgeable, but I thought as well that the batteries (maybe 2) would be sufficient and at a better price. That being said, I do need an AC inverter... but not a big one. I'm trying to avoid EMFs and inverters are usually the biggest culprits. So, rather than a regular inverter, the PPS might have the bit of AC power that I need. I'm happy to be directed to a better cost-effective solution.

And! There ya go... complicating things by suggesting 24v. I did note that that is far more popular these days. I thought that since I'm a novice, maybe I'd stay with 12v due to it being less dangerous (I don't even know if this is a thing). Anyway, if you have a moment to sell me on 24v (and I'll look for YouTube videos as well). So! Thx 4 the suggestion re: the Ecoworthy. Do you think the prices will be going up dramatically? Any other help would be appreciated as well. Thank you SO MUCH! I've been getting grouchy trying to pull this all together. Any insights regarding the cables?

 

[740GLE]

You want a PPS for AC cause you think it has lower EMF?

How do you think a PPS generates 120v AC from a DC source? Or are you saying a small 1000w Ac inverter of a PPS is about your limit of EMF? They do sell small stand alone inverters 800w-1500w.

PPS are great for fast installs but IMO limit your growth

I only mentioned 24v as it’s easier to expand as your needs grow.

 

[wme]

Here is a review on the Ecoflow 1800. Around the 19 min.+ mark he does an actual EMF test.

 

[chrisski]

Here is a review on the Ecoflow 1800. Around the 19 min.+ mark he does an actual EMF test.

Why are you trying to avoid EMFs?

If it’s for HAM radio different inverters act differently in different frequency bands.

 

[Marmatth]

Why are you trying to avoid EMFs?

If it’s for HAM radio different inverters act differently in different frequency bands.

My sweetheart is somewhat sensitive to EMFs. It's not to the point that he needs to live out in the wilderness, but we have a tester and he'd be unhappy with me if we were laying near a lot of EMFs. Behind the headboard is the cavity in the far back of the van (stow and go seats were removed) where the electrical will be stashed. Thanks for asking. Do you have any ideas of the science behind EMF exposure or whether or not it really poses a problem?

 

[chrisski]

Do you have any ideas of the science behind EMF exposure or whether or not it really poses a problem

IME you need to be exposed to large amounts of RF for it to be a problem.

IMO, emf from household devices won’t cause problems.

 

[Marmatth]

Guys! I can't tell you how much I appreciate all your help. I ended up in the hospital for a short stay; 'needless to say I've been a little under the weather. I am going to get back to this asap. I suspect prices are already going up with the tariff impact. I had hoped to get this done a little sooner. More ideas on cheaper, high quality batteries?

 

[Marmatth]

Ok! 'Here's my updated blueprint. Have I done all that's required to upgrade to a 24V system? Does it look like everything is compatible? Batteries big enough? I obviously have tailored my choices to fit within my budget. I've added the names of all my components in order to ensure that all 'fits.' Any help would be greatly appreciated. I'm hoping to buy some of the items today. Also, any insights on how to wire everything? What gauge wire, etc.? Thanks!

 

[Marmatth]

IME you need to be exposed to large amounts of RF for it to be a problem.

IMO, emf from household devices won’t cause problems.

I've added new information. If you have the time, could you review it for accuracy? Thx

 

[Marmatth]

Here is a review on the Ecoflow 1800. Around the 19 min.+ mark he does an actual EMF test.

I've added new information. If you have the time, could you review it for accuracy? Thx

 

[Marmatth]

You want a PPS for AC cause you think it has lower EMF?

How do you think a PPS generates 120v AC from a DC source? Or are you saying a small 1000w Ac inverter of a PPS is about your limit of EMF? They do sell small stand alone inverters 800w-1500w.

PPS are great for fast installs but IMO limit your growth

I only mentioned 24v as it’s easier to expand as your needs grow.

I've added new information. If you have the time, could you review it for accuracy? Thx

 

[Marmatth]

I there a reason your looking to have a portable power station as well as dedicated solar/battery system?

Is it just for the included inverter and portability?

What equipment do you currently own? Sounds like the fridge and a single 450w solar panel?

The fridge can run on 24v? If so id start with a 24v system and plan around that it’d have the best future proof.

As for maths that 2.8ah/h is best calculated in Whr. I’m assuming 2.8ah is at 12v, so

2.8*12=33.6whr

Now 33.6whr*24hrs = 806whr/day

toss in the fact you are opening up the fridge some of the time and cooling stuff down so round up to 1kwhr/day.

If you plan your battery around not having any PV generation for 3 days that’s 3kwhr of just fridge usage.

So at 24v if you have 200ah of battery storage you’re at 4.8kwhr. A good start for a van build.

Check out ecoworthy 24v batteries 100ah units, aren’t terribly expensive. You can start with one and add another if you see your usage needing it.

I've added new information. If you have the time, could you review it for accuracy? Thx

 

[wme]

Ok! 'Here's my updated blueprint. Have I done all that's required to upgrade to a 24V system? Does it look like everything is compatible? Batteries big enough? I obviously have tailored my choices to fit within my budget. I've added the names of all my components in order to ensure that all 'fits.' Any help would be greatly appreciated. I'm hoping to buy some of the items today. Also, any insights on how to wire everything? What gauge wire, etc.? Thanks!

Simplified. Solar panel to SCC. SCC to 2ea parallel 12v 100ah batteries, this is your battery system.
Power system You will need a couple of bus bars (+&-), Battery to bus bar, inverter input to bus bar (both need big wires). 24v to 12v converter input to bus bar, fridge to bus bar.
Power distribution. Inverter output to 120v ac distro panel, 24v to 12v converter output to 12 v fuse panel

 

[740GLE]

I've added new information. If you have the time, could you review it for accuracy? Thx

So I think that fridge can run in 12v or 24v

Verify in the manual, if it can run at 24v it’d be best to run it directly off the battery, it’ll reduce the losses of the step down converter.

 

[Marmatth]

Simplified. Solar panel to SCC. SCC to 2ea parallel 12v 100ah batteries, this is your battery system.
Power system You will need a couple of bus bars (+&-), Battery to bus bar, inverter input to bus bar (both need big wires). 24v to 12v converter input to bus bar, fridge to bus bar.
Power distribution. Inverter output to 120v ac distro panel, 24v to 12v converter output to 12 v fuse panel

Your idea regarding the busbar and the fridge. Does this take into acct that the fridge handles 24v? Thx again for your help!

 

[Marmatth]

So I think that fridge can run in 12v or 24v

Verify in the manual, if it can run at 24v it’d be best to run it directly off the battery, it’ll reduce the losses of the step down converter.

It can run on 24v

 

[mikefitz]

Any help would be greatly appreciated.

For your modest system stay with a 12v system, there is no need to over complicate the design. The 24 to 12v converter would not
be needed with a 12v system, ( the converter type you list are not very reliable).
You nont need any other Victron stuff for a basic system. Use two 12v batteries in parallel and a 1200 watt 12v inverter. The Victron 100/30 will be OK with the panel for a 12v system.
There is no need to consider a 24volt system unless the inverter is over 2000 watts.

 

[wme]

So I think that fridge can run in 12v or 24v

Verify in the manual, if it can run at 24v it’d be best to run it directly off the battery, it’ll reduce the losses of the step down converter.

Sorry 2 batteries in series.
The recommendation to make everything 12v is a very good idea. WHAT equipment do you currently have?