Feedback on proposed electric configuration

[thehman]

Hi,

I have been working on a spec for my electrics and plugged the numbers / spec into vunked to try and confirm battery life etc. I had a chat with vunked and they were very helpful.

Would really appreciate it if anyone can provide some feedback on my proposed set up before I start buying all the bits and pieces. It is not a full on camper conversion - more an MTB van with ability to go off grid for a period. But want access to 240v occasionally.

I guess my main questions are:

(1) How accurate are the vunked battery estimates?

(2) Are there any other ways to do this / changes I should consider to the spec?

(3) Should I include solar - Usage will be mostly UK, but do anticipate trips to Europe (but not during peak summer times). If I do include solar, would rather have a flexi / slimline panel. Or even one you can pack away.

(4) Will the batteries fit under the drivers seat (with all the other electric bits and bobs)?


Usage
Anticipate my usage profile will be as follows.

Need a maximum of 3 days ability to run on battery alone. Other times will be on EHU.

Anticipate a minimum of 0.5 hrs driving per day (probably be more, but aiming on the cautious side).

Only need 240v when on hook-up. At other times I can use 12v.

• Diesel heater
• 50L fridge
• Couple of USB ports
• 6 LED lights

Vunked show this as 62.0 Ah/day

Q. Does that sound about right?


The spec that I have come up with is as follows:

230Ah Lithium Battery Fogstar Drift
30A Victron DC-DC Charger system
Victron 20A Battery Charger System
No solar

Vunked shows this as giving me 4.4 days off grid which gives me some contingency.

Alternative spec 1
* Spec change

* Fogstar Drift Eco - 12V/100Ah
* 50A Victron DC-DC Charger System
Victron 20A Battery Charger System
No solar

Vunked shows this as giving me 2.4 days off grid. Which does not hit my 3 days or leave any contingency.

It looks like I would have to increase my driving time to 1 hours a day or thereabouts which then gives me 7.5 days off grid. But I would rather not have to commit to this driving.

Q. Would this really only give me 2.4 days off grid?

Q. Will the 50A actually charge at this rate?

Alternative spec 2
* Spec change

Fogstar Drift Eco - 12V/100Ah
50A Victron DC-DC Charger System
Victron 20A Battery Charger System
* 230w solar

This now gives me 4.7 days off grid during the winter.

Q. Will solar really increase my off grid time during the winter?

 

[doncarlyon]

230ah lithium will run the fridge and lights for a good few days. The diesel heater is the unknown, it depends how much you use it.

 

[thehman]

Hi doncarlyon,

In the vunked calculator I put the heater in as 3hrs per day (this usage indicated 7.5A total)

 

[doncarlyon]

That would be at startup, they use very little once running I believe.

Either way, the 230ah battery is the way I would go.

I thought of adding solar at a later date if needed but so far never needed it. My 100ah battery does us for 3-4 days no problem.

 

[Stay Frosty]

I think you might be over thinking things?
There are a shilt load of threads on here with medium to large installs for ideas and yes, of course you need solar, it's free electric and unties you from the grid, it also means you don't have to run your stinking engine for extra hours on end... plus saves you £5 a night EHU at the mumsy campsites I go to.
Buy the bits you need, in fact that's where you can put the emphasis on getting stuff that's fit for purpose and not just sticking to Victron... don't get me wrong Victron is good stuff but there are multiple alternative makes at multiple price points, me, I like Renogy but I do have a Victron IP30/12 charger as part of my Frankenstein setup.
Buy the bits you think you'll need or at least list them on here and the forum will chip in with anecdotal advice to help steer your install.

 

[Salty Spuds]

There’s a mountain of advice and calculations on 12volt planet’s website, in addition to the wealth of knowledge on the forum. Make yourself a drink and have a couple of hours searching and browsing. This is probably “The” most discussed topic on the forum.