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Discussion Starter #1
It'll take me a few months to get started, but I've been planning out a van based on the 3500 Extended.

My wife and I will be full time in this van. She’s retired, but I still need to work. Fortunately, I can work from wherever I have an internet connection.
These are the requirements I’ve come up with so far.

Full to queen bed (Lifting or murphy)
Shower/toilet combo (composting toilet)
Induction cook top
1-2 fans
Air conditioner (undecided on this one)
Refrigerator
20(?) gal fresh water
15(?) gal grey water tank
6 gal electric tank water heater
300+ Amp hours of lithium battery
300+ watts of solar panels
2000 watt pure sign wave inverter
Computer work surface when bed is up out of the way.
Cell phone booster
WiFi booster

Sounds ambitious to me...I'd go out and buy a Hymer Aktiv 2.0, if I had $100,000 laying about.

What do you guys think?
 

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2014, 138WB, High Roof, Gas, SW MT
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Hi,

Heating water with electricity takes a lot out of even your large 300 amp-hr battery.
Heating 6 gallons of water from 60F to 120F takes (6 gal)(8.3 lb/gal)(120F - 60F)(1 BTU/lb-F) = 3000 BTU, which is 0.88 KWH, or about 75 amp-hrs. If you both take 6 gallon showers, its 150 amp-hrs :) Most people use some sort of hydrocarbon fuel (propane, gasoline, or diesel) to do things like water and space heating as the energy use is high for a battery system.

The AC is an even larger load and tough to run off a battery. A 13500 BTU/hr Coleman RV AC uses about 1600 watts when running, or about 130 amp-hrs of your battery for one hour of operation -- maybe somewhat less, since it won't be on all the time. Good insulation and window covers that block solar gain through the windows will help, but its still hard to run an AC all day without shore power or a generator.

I'd start with looking at your electrical loads first -- if you can minimize them it makes the whole electrical system simpler, cheaper, smaller, and lighter in weight.

Composting toilets are great!

Gary
 

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GaryBIS is on the mark here IMHO. I’d look at the process of designing using the following questioning steps.
1. What do you plan to do in the van? ie. shower each day, 5 hours at the computer, guests for dinner occasionally? etc.
2. What are the best/simplest/good enough ways to provide for the above needs.
3. What are the possible technologies to supply the ways in #2
4. What resources must be carried or available to provide those technologies.

Open your mind to all possible solutions not what you preconceived the solution would be. Gary makes a couple of points concerning this. You could solve the AC issue with a bigger battery set fueled by more solar cells but many have tried and failures in that are many as well. If you decided you need AC in step 2 and 3 there are ways to have it, just not via solar.
 

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2014 3500ext Gas - VA
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I'll second Gary's and RD's words of wisdom.

I originally planned to run my AC and heat water off my battery pack... so I invested in my electrical system... 400w solar, 440 Amp-Hr AGM battery bank, 3000w pure sine wave inverter, and a Honda eu2000i gen as "backup". My system "worked" but seeing the current draw to run the AC even for 15 minutes made me realize I was going to kill my batteries... also, despite lots o' insulation, a metal box takes a long time to cool once it is heated up... you can knock a few degrees off the air temp in a couple minutes but the interior surfaces will heat the air right back up. In steamy Virginia, it takes a couple hours to truly cool the interior to comfortable sleeping temps. Similar experience on power draw for the hot water system (6 gal point of use heater).

I quickly came to the realization that I will either be on shore-tie or generator to use HVAC or hot water heater. I re-wired my system and have been very happy since... I just wish I had realized this earlier as I could have downsized my battery bank, inverter size, and solar... actually, I like having the 400w of solar just because. But I could have saved precious space and several hundred $ on the smaller batteries and inverter. Oh well, lessons for my next build.
 

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Or Safari Condo on a Promaster: http://www.safaricondo.com/en/motorises
$94K CAN or $68K USD, a bargain.
I looked into getting Safari Condo. For us in the US, you have to buy a US spec van, then get on their wait list approximate 12-18 months. Bring them the van when it's build time. Cost depends on what all you want. $35k-$45k
 

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Discussion Starter #8

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That's a great idea! Where would you mount one of those on a van?
Anywhere, but preferably bolted to the floor, of course. I'm mounting ours over the rear axle, under the bed, next to the fresh water tank. You tap into the PM's heater hoses under the hood (same as a rear heater install) and run a pair of heater hoses back to the unit. I'll probably run mine under the van most of the way. Might even run them alongside the grey tank for some freeze protection. Here's one of the isotherm threads. There are others.
http://www.promasterforum.com/forum/showthread.php?t=45265&highlight=isotherm
 

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Discussion Starter #10
I looked into getting Safari Condo. For us in the US, you have to buy a US spec van, then get on their wait list approximate 12-18 months. Bring them the van when it's build time. Cost depends on what all you want. $35k-$45k
Love that van. But that's just makes it too tough to get one.
 

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Queen bed? You gave a long learning curve ahead ;) don't worry we shall be happy to help!
 
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