What type of electrical system?

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GeorgiePorgie

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I'm a real newbie with little mechanical knowledge or skill and I am trying to figure out what kind of (inexpensive) van I should buy and what I need to do to make it a comfortable full-time home. I do not intend to pay for camping, and probably will not have many chances to charge the batteries from an electrical outlet.
I need a fridge and CPAP system every day and want to do most of my cooking myself. I'm wondering what kind of electrical system would be best for me.
It sounds like most frugal people have a 12 volt system, but also use propane for cooking and heat. Is that the least expensive way to go? I rather just use electricity for everything, but it does not seem  that many van dwellers do that from the videos that I have seen. I probably would mostly cook simple dinners in the evening and would not need electricity (or whatever) earlier on most days. However, toast in the morning is a must.
Should I install a 12 volt system and try to get mostly 12 volt appliances or is a 120 volt system with regular appliances more convenient? I don't want to buy a new (12 volt) CPAP machine as mine is pretty new and expensive. There are also other appliances that would be a lot easier to find in the 120 volt section. What do experienced van dwellers think?
I don't have a lot of money, but hope to buy a van, fix it up and put in a decent electrical system (solar?) for around $10,000.
 

Cammalu

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You can probably get a 12 v cord for your cpap


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Almost There

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There's a very good reason most of us don't use electricity for anything that relates to heating (cooking, toaster, heater etc)...it takes a tremendous amount of energy to do so. When you're supplying your own electricity and paying for the infrastructure (as opposed to getting it from the electric company), one begins to appreciate that it's the worst possible scenario.

Propane is inexpensive, easy to obtain and does a wonderful job of creating heat. Your morning toast will do just fine using a propane or butane stove and an inexpensive toaster from the camping section of WalMart.

12 V systems need to be designed for an individuals real life usage. One starts with the electrical needs, sizes the batteries to fit that need and then sizes multiple ways of charging those batteries - solar, generator and from the engine while driving using a solenoid. Lots of decision making to be done but it doesn't need to be done before you even figure out what vehicle to buy.... :D

Your CPAP, btw, probably comes with a little 'brick' in the middle of the power cord...it's taking 120V down to a much lower voltage, probably around 19V IIRC. Most of the CPAP users here have found 12V adapters for their model machine. The alternative is to use the machine with an inverter (it changes 12V to 120V) but there are inherent inefficiencies in doing that way.
 

John61CT

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Yes I agree that 12V electric should not be used for heating or cooking.

If you're flush and "need" a microwave that can be doable for a few minutes per day, but even then would require a bigger system.

And yes see if your CPAP maker sells a car adapter, or reverse engineer the voltage, polarity and plug size, using an inverter should not be necessary.

Best value by far for batteries is

Pairs of 6V Duracell (actually Deka/East Penn) deep cycle golf cart batteries, about $180 per 200+AH pair from BatteriesPlus or Sam's Club. 

Have yet to come across anything trustworthy cheaper at lower capacities. You would be able to go longer between recharges to Full with 2 pair rather than just one.

12V so-called "deep cycle" from big box or online are all basically a fraud, all things being equal won't last even a quarter as long as the GCs. And not even cheaper per AH anyway.

FLA is much more robust than AGM.

Charge sources:

If the fridge is critical for meds as well as the CPAP, plan for a little generator for bank charging in the morning, as well as some solar to get the batts to 100%.

Solar-only is tough to pull off unless you're always in sunny places and parked out in the sun all day.

Finding free or cheap places to recharge from shore power overnight would be fantastic, but can be a challenge.
 

jonyjoe303

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Get a large solar panel, 240 watt or bigger, that should fit on most minivan roofs. With a cheap mppt controller (victron or ecoworthy) that will get you at least 10 amps of charging power. Battery get at least a 100ah agm that way you can keep it inside your van and not worry about it leaking or servicing. As you learn you can always upgrade later.

If your living fulltime in the van, get alot of foam insulation for your van, forget the roof vents (you can install side vents) and get a swampcooler. Swampcooler will easily run on solar and keep you cool. Propane and a mr heater will take care of the cold weather. Without the foam insulation and swampcooler you will never be comfortable inside your van. Fans only blow air around, swampcooler lowers the temp of the air and gives you an actual cooling effect. This will allow you to park in the sun all day long to charge your batteries. I never park in the shade or near trees.

For heating food up you can get one of the roadpros lunchbucket cookers, its what I use to heat up all my food for years, I just eat mostly can goods, put some aluminum foil on the lunch bucket, pour the cans in there and I also put bread on top of the foil and heat everything. 20 minutes later its steaming hot. Totals amps used during the 20 minutes is 6 amps. Easily handled by the battery. 

Everything revolves around the big solar panel, you get that and you have practically unlimited power. Everything on my van runs off that big panel, 100 percent solar, never been hooked to shore power or alternator. A smaller 100 watt panel might get you only 5 amps, that will help but you have to watch how you use every amp. That why I recommend the big panel, big difference between 5 and 10 amps, you wont regret having a large panel.

I payed 200 dollars for my 240 watt panel, 102 dollars for my ecoworthy controller, you can find good deals if you look around, well within your budget.
 

John61CT

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Victron and ecoworthy solar controllers should not be lumped together

The former is very up to date, well designed, precision engineered and tremendous build quality, worldwide 5-year warranty and very widely used in marine installs.

Yes their lower-capacity SCs are tremendous value, but they should not be called "cheap".


Also, sorry to pick nits, but the phrase "6A in 20 minutes" is incorrect and unclear

If the lunchbox cooker uses 6A, then in 20 minutes it uses 2AH.

If it uses 6AH in twenty minutes, then it draws 18A.


Swamp coolers are only useful in dry climates.


The cost for AGM long term will be much **higher** than FLA, most people do not need to build an enclosed vented box, just secure them from shifting and protect the top from shorts. And finally, if both fridge and CPAP being critical 100AH is not enough IMO unless getting fully recharged every day.
 

S Cello

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My rudimentary calculations regarding swamp cooler use while boondocking was that i couldn't carry enough water to keep it running for extended stays, say 2 weeks. Am I wrong?
 

frater secessus

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Depends on the location and the amount of time you run it.  I recall reading ~1.5-2gals/day.

Working backwards from the residential numbers here (pdf), it takes about 7gals/hour for 1500sq ft house.  For a 50sq ft van that would be .23gal/hour.  So 1.87gal/day for 8hrs of cooling.  About 2 gallons a day.
 

tx2sturgis

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frater secessus said:
 So 1.87gal/day for 8hrs of cooling.  About 2 gallons a day.

I wonder how well this would work with recycled and filtered gray water (or filtered stream or lake water) ...I haven't tried it myself, but I suppose it could work. Don't see why not....

:huh:
 

John61CT

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Fresh outdoor sources no problem, grey could easily require more treatment than it'd be worth.

But with a cheap DIY setup, cheap to experiment, worse case scrub with bleach, launder the cloths
 

John TF

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I am going to agree with most of what has been said , try to never use electric when needing heat or running anything with a motor - like a fridge with a compressor .
Try to use low consumption sources [ that do not make heat or run a motor ] like lights , radio .
To get a feel for getting started , make a list of all your gear , make & model and most importantly there power ratings / consumption on the label - usually on the back .
Now for what you think you may want , either go to store front , or internet search , and look under spec.s and make notes of power supplies needed , again for both newbies [ to learn & get a feeling for power needed , & for those with more knowledge - to have the numbers to workout Ohms law - https://en.wikipedia.org/wiki/Ohm's_law .
This something that anyone even remotely thinking / working with anything electrical should know ,or should learn .
Some generalizations about solar , and leaning towards the problematic issues with mobile solar systems .
For most battery systems [ lead acid , the most bang for the buck , is still FLA - Flooded Lead Acid - deep cycle { not marine } ]
When buying quality [ not high priced ] FLA deep cycle batteries , and treating them correctly , you are going get the most performance for the least money spent .
This is generally , you can spend more on other types [ as an example some lithium chemistries ] but that is another kettle of fish .
Every type of battery has goods & bads , but to keep it simple , the easiest to find , cheapest and longest lasting is the above battery .
Anything else has special uses , and have special pricing , this means high price and typically trades off performance for the special - AGM , sealed , spiral wound plates etc.
So sticking with the FLA battery , to get them to last a long time requires treating it according to specifications , correct charging & discharging .
What is problematic with RVing , is not enough space to mount enough solar on your van / what ever to get a good sized battery bank charged correctly - correctly means that a relatively high charge rate as soon as possible [ this is a big part / or 2 part of long life ] " soon as possible " means charging as soon as you stop using the battery , battery sulfation is a process of crystal growth that is almost a constant process , the lower the the SOC - State Of Charge the fast the growth , also the longer the battery sits in any condition [ except charge condition ] , so basically its a constant process .
Again for long life , shallow discharge [ normal deep cycle is considered not more than 80% discharge { but not more that 50% is best , or less } ] .
With a workable battery bank [ for general full time RV living ] a min. would be something like the golf cart 6v batteries , & using 4 of these , 2 pair in series for 12v , then those 2 pair in parallel - for more capacity .
My last battery bank was this , except for using 4 Trojan L16's , they lasted over 12-13 yrs. using furnace and air conditioning .
This is the big issue with mobile / RV is having enough solar to get a high charge rate for this battery bank , at least 50 - 100 amps , without the ability to charge correctly , this shortens battery life , part of that is an equalizing charge [ this basically boils the electrolyte to do a couple things , sluff off the plates & 2nd force all cells to be equal ] .
 

John61CT

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Trojans deep cycles are great, including L16s, definitely a step up in quality from these
John61CT said:
Pairs of 6V Duracell (actually Deka/East Penn) deep cycle golf cart batteries, about $180 per 200+AH pair from BatteriesPlus or Sam's Club.
which are the cheapest ones I'd recommend.

But for a newbie starting out getting better quality may not pay off, as there's a learning curve to caring for them properly, and some "unavoidable" situations guarantee an early death, sometimes replacing a bank more frequently makes economic sense compared to the necessary remedies.

So "first bank cheap" is a good rule of thumb.
 

GeorgiePorgie

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jonyjoe303 said:
For heating food up you can get one of the roadpros lunchbucket cookers, its what I use to heat up all my food for years, I just eat mostly can goods, put some aluminum foil on the lunch bucket, pour the cans in there and I also put bread on top of the foil and heat everything. 20 minutes later its steaming hot. Totals amps used during the 20 minutes is 6 amps. Easily handled by the battery. 

Are the Roadpros Lunchbox Cookers powered by 12 volt power? I have seen them advertised, but could not figure that out.
 

jonyjoe303

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[font=Verdana, Arial, sans-serif]"Are the Roadpros Lunchbox Cookers powered by 12 volt power? I have seen them advertised, but could not figure that out."[/font]

[font=Verdana, Arial, sans-serif]Yes they max out at 11 amps and once its heated up it goes down to about 9 amps. If you buy one replace most of the cable, oem is 16 gauge wire, too thin for 11 amps. The 16 gauge wire gets very warm during use, I cut most of the 16 gauge off and left a little by where it comes out and use 12 gauge wire. Also replace the cigarette plug those are cheap and will fail from overheating. You replace those parts and it will last you years, mine is going on 5 years. They are good when you want to heat up something quick without using gas.[/font]

My roadpro with the xt60 connector, and just regular aluminum foil instead of the special inserts they sell.
a roadpro.jpg
 

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DLTooley

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I've run my cpap off of a 50 watt panel and a walmart deep cycle. It isn't an ideal system, but it was a great **learning** system. You can't run much more than that.

I've upgraded to a 100 watt panel, fix mounted, and have kept the 50 as a semi-portable adjunct. I now have extra power during solar hours, which I use to run a 12v freezer and charge my laptop. Next up is a Victron Controller. I'm holding out for a better lithium option/price before I upgrade to a pair of 6v golf carts. I may not make it.
 

tx2sturgis

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jonyjoe303 said:
[font=Verdana, Arial, sans-serif] Also replace the cigarette plug those are cheap and will fail from overheating. You replace those parts and it will last you years, mine is going on 5 years. They are good when you want to heat up something quick without using gas.[/font]

That's about right....I went thru four of them in a 37 year driving career, mostly in the first 20 years or so: they were originally marketed as Burton Lunchbox stoves....in the later years of my career, inverters and in-cab microwaves were becoming more affordable and available, so I used those stoves less and less.

They work well, if somewhat slowly, but you just need to take precautions as outlined above, and also, place the unit on something that will not be damaged by heat. They wont start a fire, but they COULD melt nylon or other light plastics, if placed against them. 

I only used them while driving: I would pull over in a rest area, pour in some soup, stew, leftovers, or a frozen burrito, whatever, then drive for an hour or two. I could tell from the smell when it was ready.

Pull over, have a meal, 10 minutes later, I'm rolling again.

I won't talk about manifold and turbo cooking on the engine, that's for another thread and another day!

:cool:
 

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