Originally Posted by Flakwagon
Hey Kingnever, thanks for your interest. Glad to hear you are joining the van world and are doing it yourself.
I spend a lot of spare time researching energy systems, on a scale from van to small town. Prepare yourself:
1. In Short, the answer is cost. 12V and 225Ah for $240 total is hard to beat. They are Trojan T105 I got such a good deal on them because my dad ordered 16 of them for his solar system and I bundled with him. That convenience was also a factor. If I could do it over again and money wasn't so much a factor, I would have likely bought sealed or gel batteries. If money was really no object I likely would try a lithium setup.
2. The charger is a Noco Genius G7200. My Inverter Is a Krieger 2000w. The charger works excellent but at a rate of 7.2Ah it takes a longgg time (16 hours) to fully charge a depleted 225Ah battery. I would get one that could full charge a dead battery in 6-8 hours. One rated for 20Ah would do the trick.
3. Yes. That is something I find myself researching. I hope to have either van sold or a new fridge by the end of winter. The Dometic 3-way fridge I am using has an absorption style cooling system. Not to mention it is almost 40 years old. Its still works but if I had to guess I am drawing 15 amps in 12v mode. Its also either ON or OFF. A modern fridge with a Danfoss compressor might draw 5 amps while running and 0.5 amps in standby mode. I do think that would solve our energy problem. The fact that I have only seen the unobstructed sun 5 times in 4 months isn't helping my solar system much either.
In all honesty I was very underwhelmed by the amount of light these things put out. In the dead of night they are alright, but the cool white color is very piercing if you are looking towards it.
The travel style and energy needs of everyone are different and that is going to be the ultimate factor in what kind of energy system would work best for you. There is a big difference in what I would advise to install for a weekender and a full time live in van. Geographic area is also a factor.
A lot of the problems we ran into with our electrical system did start appearing until we were a month into our trip and much further north than Florida. We slowed way down once we got to Alaska as well and weren't charging the batteries with the alternator as often. We are much further from the equator so our solar benefit is much lower.
The best way to figure out your energy needs is to add to up the theoretical amp draw for all the appliances you are thinking about using.
What appliances are you thinking about installing that use electrical power and how often do you intend to use them?
What type of power do your appliances use? (12v,24v,110/120V)
Do you plan to run a generator?
Do you plan to charge you battery system with your engine?
Are you looking at installing a solar system on your van? If so I can overload with information on how I would do it over. I have been working on a few different theoretical systems that I think would much better meet our long term need for living on the road.
Thank you so much for the detailed response! That's an incredible deal on batteries, I paid half that for a sealed lead acid group 65 battery just yesterday that's probably only 65-75Ah!
We're going to start off with an extremely simple house battery setup. Our van came with a factory auxiliary battery mounted on the passenger-side frame rails. The battery is isolated from the starter battery, and powers the trailer harness. I'm basically just going:
Battery --> meter --> low-voltage disconnect module --> 30A circuit breaker --> fuse panel
This should let us experiment with how much energy we use, and we should be able to re-use a lot of these components later on if/when we upgrade the system - but other than the wire, everything was dirt cheap anyway!
We're "weekenders" and aren't planning on living in the van full time and our power needs are modest. Vent fan (5A peak), LED lights, cell phones and likely a 12V ARB fridge later on and potentially a 12V TV (although I'm liking that idea less and less). Our "stretch" power goal would be to be able to run a couple of 12V bunk warmers for the really cold months, but I suspect we might not need to.
Ideally, we'd be able to stay off grid for 3 or 4 days without worry, and my original goals were lofty and involved solar, lithium batteries, shore power options and 300+Ah of batteries but costs and complexity got out of control immediately.
Solar seems like it would be a great way to extend our system's boondocking capabilities but we live in the Pacific Northwest and honestly do the bulk of our camping during bad-weather months, so I'm concerned that solar adds a lot of complexity / cost for little gain, but really don't have much of a clue.
I think our ideal setup would be a relatively large lithium bank primarily charged from the alternator, with shore power options and a solar panel that wasn't permanently attached to the roof - but that's an expensive setup and I am beginning to suspect would be total overkill for us. Lithium right now seems to be in a state where people are still figuring out a lot of details, like float charge voltages and cell-balancing. The cost is just still too high to me to experiment with that tech, but who knows!
How well does your solar setup work in Northern environments for you? And how long do you have to run your van to bulk charge your batteries to a reasonable point? It seems like getting a SLA bank charged from 80% --> full is an hours-long process.
Also - I'd love to know what bed you went with. We haven't started looking at options yet but I am going to be extremely picky about the bed, given that this thing is basically just a bed on wheels with a few batteries in it.