Planning a Skoolie

[aippolito184]

I was hoping to get a reality check on some ideas and ask a couple of questions. This is the first post I have done a lot of reading but maybe not enough!

Battery

The most important thing I need to do right now is to select and budget components. The battery is the biggest question, my priorities are:
1. Safety- myself, my wife and my 2 & 4 yo children will be on this bus sleeping full-time for a 2-year adventure.
2. Cost - would like to spend as little as possible but I need a lot of capacity, I am however willing to give up space and baby them (temp control) I am also willing to build my own battery.

I am thinking a higher voltage battery system (48V?) is better? Lower amps, less cabling costs, and higher efficiency?

I have watched a few videos with high power systems that are powered by LEAF batteries. They seem cheap but I have watched enough of Will's videos to know he is against them. Why? What are the drawbacks if I don't need 1c discharge just a lot of capacity?

If I build my own cell should I incorporate spaces? I hear a lot of talk about temp control but if you put a nut spacer between each cell and forced air through an inclosure the batteries would stay cool? I was planning to alternate the spaces if there are multiple stacks for more efficiency of cooling.

Panels

I would like to pack every watt up there I can but don't want to waste money if I can capture all the power I'm receiving. Power density would be nice to free up space for a roof deck or something cool. Also, durability is a concern. Does anyone have genius recommendations?

Inverter (s?)

I am thinking of a lot of AC appliances, two AC units, stackable washer dryer, dishwasher, fridge, stove& oven. Should they be on different inverters to save battery? Always on items on one and then each of the others on their own. Or is it better to group them up to a certain capacity (ie 3kW each)?

Sorry for the rambling nature and if any of these were easily searchable.

Anthony

 

[MisterSandals]

You should start by doing an energy audit so you know how much energy you actually need. Energy Audit.

If safety is so high on your list, the safest battery(s) should be equally high on your list. That would be off the shelf BattleBorn batteries (does not meet your "spend as little as possible" goal) or self built LiFePO4 batteries. Or perhaps some lead acid/AGM batteries.

And, based on your energy audit, you should select a voltage based on that rather than jumping directly to 48v, because 48v can kill you or your loved ones. Maybe its appropriate, maybe not; but for safety I would lean towards not.

 

[Dzl]

Hi Anthony,
Welcome to the forum.

Below is my 2c, I am not an expert, but I do have some input that may or may not be helpful.

Battery

The most important thing I need to do right now is to select and budget components. The battery is the biggest question, my priorities are:
1. Safety- myself, my wife and my 2 & 4 yo children will be on this bus sleeping full-time for a 2-year adventure.
2. Cost - would like to spend as little as possible but I need a lot of capacity, I am however willing to give up space and baby them (temp control) I am also willing to build my own battery.

I am thinking a higher voltage battery system (48V?) is better? Lower amps, less cabling costs, and higher efficiency?

A good BMS plus a DIY lifepo4 battery seems like it would be a good fit in terms of safety and cost.

As to voltage, It is my opinion that there is no voltage that is better than the others, 12v, 24v, and 48v all have their place, and its a matter of selecting what best fits your needs. Generally I think 12v and 24v make the most sense for portable, mobile or marine builds, and 48v makes the most sense for off-grid homes, cabins, etc. There are a number of reasons for this, and a number of good threads discussing pros and cons if you search. Buses fall somewhere in between typical vehicle based builds, and off-grid tiny homes. Many buses (including yours from the sound of it) for one reason or another choose to wire the bus in 120V AC as a home would be wired. This makes 48v a more attractive option, but 24v would be suitable as well.

There are savings in cabling costs, and there is a bit of efficiency to be gained, and lower amps are good. However bear in mind, for a vehicle based build, the length of wire needed for the 48v DC system may be pretty minimal (Charge controller --> Battery --> Inverter or DC-DC converter) so the efficiency and cost savings may not be a big factor. Also bear in mind that 48v--while not unsafe--is stepping outside of low voltage DC territory (both legally and practically).

Usually the battery bank voltage is largely determined by other parts of the system, normally inverter size, and how much power you require at a given time. Other components including charge controller and BMS can be factors as well.

Many people have many rules of thumb for max inverter size for a given voltage. For me, I ballpark 2k-3k as the top end for 12v, 4k-5k as the top end for 24v, 48v for anything higher than that. Nothing true or set in stone about these numbers, just what I use.

I have watched a few videos with high power systems that are powered by LEAF batteries. They seem cheap but I have watched enough of Will's videos to know he is against them. Why? What are the drawbacks if I don't need 1c discharge just a lot of capacity?

As I understand it, the gist of it is:
1. EV batteries tend to be riskier/more dangerous battery chemistries than LiFePO4
2. EV batteries are usually being sold used (for what reason were they replaced?)
3. EV battery banks can work fine, and have some advantages, but are not the best option for the beginner or even intermediate battery builder.
3. The potential difference in cost between bargain LiFePO4 and bargain used EV cells does not justify the added risks.

If I build my own cell should I incorporate spaces? I hear a lot of talk about temp control but if you put a nut spacer between each cell and forced air through an inclosure the batteries would stay cool?

If you are hearing a lot of talk about spacers and forced airflow, its likely this is either for EV's or another high C-rate application which is not very applicable to low C-rate energy storage applications. Based on the data I've seen, stay below 0.5C continuous and your batteries will stay pretty close (within a few degrees) to ambient temperature.

It is my opinion that securing your cells well should be the primary consideration in a mobile context.

Panels

I would like to pack every watt up there I can but don't want to waste money if I can capture all the power I'm receiving. Power density would be nice to free up space for a roof deck or something cool. Also, durability is a concern. Does anyone have genius recommendations?
[/QOUTE]

I think this is pretty straightforward. Simply a matter of choosing the panels that allow you to fit the most Watts in the square footage you have available. If you want to get real fancy you could get a second charge controller and have slide out panels for when you are stationary, but personally as cool as this sounds, I don't think the juice is worth the squeeze unless you really need that extra power and will be stationary in sunny places frequently enough to jsutify the cost.

Inverter (s?)

I am thinking of a lot of AC appliances, two AC units, stackable washer dryer, dishwasher, fridge, stove& oven. Should they be on different inverters to save battery? Always on items on one and then each of the others on their own. Or is it better to group them up to a certain capacity (ie 3kW each)?

Damn you are bringing the kitchen sink and then some! You need to find or approximate the power draw of these devices and put it all in a spreadsheet. The two most important numbers are how many watt-hours a day will you consume, and how many watts will you use simultaneously.

I would suggest you consider a gas stove/oven, or at least keep an open mind about it pending the results of your energy audit.

As for the inverter a split phase inverter (such as the Magnum MS-PAE), or two single phase inverters configured to provide split phase power (such as the Victron Multiplus). This opens up the ability to use 240VAC appliances and A/C's which are often somewhat more efficient.

Regarding efficiency of a multi-inverter setup, It could make sense to keep your always on AC devices on a separate smaller efficient inverter, but this depends on the specifics of your setup. Often people do this in smaller systems where the fridge is the only always on AC device, this strategy may or may not be able to be effectively adapted to a bus with a lot of AC appliances and circuits. Its certainly worth exploring.

 

[DASH]

Here's a guy that uses solar for all his electrical needs, including running his air conditioners, stove etc for his bus. It should give You an idea of what's involved going completely solar. I think he spent about $16,000 for the solar/battery/invertor. This is the first R/Ver I know that is totally dependent on Solar, and does not have any other electrical backup (although he'll probably buy a small generator for emergency use). This guy posted this video on here. So maybe, You can contact him for additional information.

 

[aippolito184]

Thanks so much for all the input. A question about the battery voltage, if 30V is safe would 36V be a good middle ground between power and safety?

 

[aippolito184]

Is this too good to be true? Seems cheaper than anything else out there and already assembled.

36V A123 LiFePO4 Performance – BigBattery.com

bigbattery.com

 

[Dzl]

Thanks so much for all the input. A question about the battery voltage, if 30V is safe would 36V be a good middle ground between power and safety?

I wouldn't go that route. Its a relatively non-standard voltage, and will make sourcing components more difficult and your choices will be quite limited. I would stick to 12v/24v/48v, it will cause less headaches in the long run.

Also define what you mean by "power" here, are you thinking in terms of inverter power output? Do you have a ballpark of the max power (Watts) you would need at one time?

 

[Dzl]

Here's a guy that uses solar for all his electrical needs, including running his air conditioners, stove etc for his bus. It should give You an idea of what's involved going completely solar. I think he spent about $16,000 for the solar/battery/invertor. This is the first R/Ver I know that is totally dependent on Solar, and does not have any other electrical backup (although he'll probably buy a small generator for emergency use). This guy posted this video on here. So maybe, You can contact him for additional information.

Cool video and very cool bus!

Based on the components he listed, here is a rough sketch of the capability and cost of the system. His 16k estimate seems pretty accurate for the core electrical system, maybe a bit on the low side.

Batteries	8 x Battleborn	10,240 Wh	$7600
PV Array	14 x 327W Sunpower	4578W	$1540
Charge Controllers	2 x Victron Smartsolar 150 | 70	140A output (3,600W)	$1200
Inverters	2 x Multiplus 3000	6,000W / 12,000W (30s surge)	$2600
12V	1 x Victron Orion DC-DC	70A	$140
			$13,080 + cost of wire, components, etc

I think a similarly sized system could be done for substantially less. Switching out the Battleborns (clearly the sponsors of that video) for DIY batteries would save maybe 3-6k, switching to 48v would save $600 in charge controller costs.

 

[namesgolden]

If you don't already have the bus I would suggest going with a class A motorhome.

I snagged a 1997 diesel pusher with a slide for 10k last fall and was able to move right into it.

I'm not a metal or wood fabrication person, but I can maintain anything.

 

[DW SD]

Will your primary loads be AC (110V) or DC like 12V motorhome? If the prior, 24V or 48V would probably be better due to efficiency.

You might look in to a vintage Bluebird Wanderlodge. They are well built, functional out of the box and not much more $ than a Skoolie, especially by the time you buy all of the interior fittings and appliances. Not to mention conversion time.
My first Wanderlodge was a 35' 1983 pusher. New, it was $330k in 1983. I bought it with 160k miles, great paint and interior layout for $23k and a rebuilt engine. (most never need rebuilding, as they are 1M mile chassis. But the owner ran the wrong oil.)
I installed new floors, solar, electronics, and upholstery. It is still going strong after 8 years with me and 2 with another. It saw a cross country trip immediately when he bought it.

I've added 560Ah LiFePO4 DIY 12V battery to my newer Wanderlodge. It is a great fit. I stayed native 12V since most of my loads are 12V. But I still have a 3000W inverter to run TV, convection oven, one (of the two) AC unit.

cheers,
Doug

 

[aippolito184]

If you don't already have the bus I would suggest going with a class A motorhome.

I snagged a 1997 diesel pusher with a slide for 10k last fall and was able to move right into it.

I'm not a metal or wood fabrication person, but I can maintain anything.

I have looked in to this for a while, I have heard a lot of people say that old motorhomes are money pits. They are not meant to live in full time and degrade quickly, the systems are proprietary and $$ to fix. The skoolie has all household appliances and materials. I am looking at a cost of maybe 25-30k.

What is your opinion on this? How many items have needed repair in your MH?

 

[aippolito184]

Will your primary loads be AC (110V) or DC like 12V motorhome? If the prior, 24V or 48V would probably be better due to efficiency.

You might look in to a vintage Bluebird Wanderlodge. They are well built, functional out of the box and not much more $ than a Skoolie, especially by the time you buy all of the interior fittings and appliances. Not to mention conversion time.
My first Wanderlodge was a 35' 1983 pusher. New, it was $330k in 1983. I bought it with 160k miles, great paint and interior layout for $23k and a rebuilt engine. (most never need rebuilding, as they are 1M mile chassis. But the owner ran the wrong oil.)
I installed new floors, solar, electronics, and upholstery. It is still going strong after 8 years with me and 2 with another. It saw a cross country trip immediately when he bought it.

I've added 560Ah LiFePO4 DIY 12V battery to my newer Wanderlodge. It is a great fit. I stayed native 12V since most of my loads are 12V. But I still have a 3000W inverter to run TV, convection oven, one (of the two) AC unit.

cheers,
Doug

Right now it seems most of the load will be AC which is why I was looking at higher voltages. Glad I was on the right track. Wanderlodges look great, I really don't want a black tank.

 

[namesgolden]

I have looked in to this for a while, I have heard a lot of people say that old motorhomes are money pits. They are not meant to live in full time and degrade quickly, the systems are proprietary and $$ to fix. The skoolie has all household appliances and materials. I am looking at a cost of maybe 25-30k.

What is your opinion on this? How many items have needed repair in your MH?

Super old gassers could be an issue, but 95+ diesel pushers are solid. Built like a greyhound bus (motorcoach frame) with industrial engines (8.3l Cummins in mine), air brakes air shocks. Great turning radius. The transmissions (Alison) are made for high speed cruising. Super comfortable.

Our rig was $140k new, that's about $225k of today's money. We paid $10k last fall, it had 100k miles on it with an extensive maintenance history. Live in it full time since early February. One 2000mile round trip before covid

Systems are all standard motorhome stuff you can buy from any RV shop, though I get most of my stuff from eBay. RV stuff is made to be reliable and exposed to the vibrations and problems of mobile gear.

No major maintenance yet. Lots of small upgrades or standard maintenance you expect to do on any vehicle.

Only one issue so far. The rear brake drums surface rusted to the shoes after driving in the rain, had to jack up the rig and tap on the shoes with a hammer and pipe -- apparently a common issue with any air brakes system since the shoes are always in contact with the drum when there's no air pressure.

Changed the propane/ac fridge out to a regular residential fridge.
Rebuilt the water heater (new valves, ignitor. $50 total)
Cleaned the a/c coils
Fixed some luggage door handles (CLR soak)
Removing generator and replacing with modern inverter drive unit.
Upcoming upgrades: propane range with oven, couch, solar.

We had to have diesel for our yearly cross country trips that take us through PHX/Vegas in August. It was cheaper to buy the motorhome than a decent used diesel pickup.

 

[DW SD]

If it was me, I'd install a large DIY LiFePO4 battery bank with solar in something like this:

birds-rule

www.buybyebluebird.com

This is a premium cost due to the stellar condition. I sold my 35' PT for $40k, but it was also in similar condition with solar, new tires and modernized interior (new floors, and upholstery).

Or get a small loan:

RVs For Sale - RV Trader

RVs For Sale: 0 RVs - Find RVs on RV Trader.

www.rvtrader.com

Do a little haggling on the first one and you are right in your budget.

You will make up the difference in upfront costs alone on resale. Spend $25k to $30k for a skoolie and they end up hard to sell when it comes time. And that's if you can keep yourself on budget.

These things are loaded for bear with massive generators, large holding tanks, pass through storage bays, large interior kitchens and closets, multiple AC units, propane and electric and chassis heaters. You'd be lucky to create something so functional with as much storage for $25k to $30k. Not to mention ride quality and ease of driving.
The chassis is designed for 1M miles, just like an over the road bus. They are built SUPER well. Like a brick $hithouse.

There is a guy on the wanderlodge owners group forum with 900k miles on a similar rig. Original owner used to work for Nascar as an event marketing guy and followed the circuit for 30 years. His is in as nice of condition as both of these. And has never had an engine rebuild. I think the trans was rebuilt, but can't remember the exact details.

You could put a composting toilet in. Some do that. I wouldn't but just me.

Cheers,

Doug

 

[namesgolden]

You'd be lucky to create something so functional with as much storage for $25k to $30k.

This! Unless you're a master fabricator and dont value your free time, the storage benefits alone are worth going to a RV style motorcoach

 

[DW SD]

If you haven't seen this blog, check it out. For several years now, this family is building their dream bus / camper.
Looks like a LOT of work! Maybe he'd share the hours and $ spent.

Beginning from this Morning

Thoughts, stories and ideas.

www.beginningfromthismorning.com

 

[aippolito184]

I really appreciate all the suggestions. One of the other reasons a choose a Skoolie is the ability to be off-grid with as little fuel as possible. It is my understanding that it is not feasible to install enough solar/batteries to run the appliances in an RV, certainly not the AC? I am a newbie please correct me!

 

[DW SD]

Hi Airpolito,
Not true at all on off grid capability.
Can you see my (2 of 3) panels?

I have a propane and AC fridge (Dometic.). Running on propane the fridge is very efficient. I also keep a large 12V compressor fridge (cooler shaped) for drinks.
900W of solar (3 x 60 cell residential panels) fit beautifully. I can off-grid with a bit of sun indefinitely without the generator. A few weeks ago, I collected 250Ah with partial shade until 11a. We use 90Ah to 150Ah / day depending if we use electricity for any cooking.

I have 560Ah DIY LiFePO4 batteries ($1500). They'll last me 4 or 5 days without sun. I also cook with an AC hotpot regularly, have an Nespresso maker, microwave / convection oven, etc.

Yes, hardly roughing it.

I can also run an AC unit from the batteries. I'd estimate 60Ah per hour of use - so it draws a lot and that is if it cycles off 1/2 time. But if really hot, I turn on the generator during the heat of the day. That costs $3 / hour. (1 gallon / hour).

More solar would offset, but I struck a good balance. And rarely camp somewhere very hot (or very cool).

My newer rig cost someone $500k new in 2004. It is now 1/5th of the price.

Depreciation is your friend on used RVs. Many care for them religiously, including garaging when not in use.

Good luck!

Doug

 

[DW SD]

This was the first one, PT-35 (PT refers to Pusher Tag - so rear engine): Much more skoolie - like. But with planned under floor storage bays. Similar could be had for $30k to $40k.
A friend just bought a similar 40' for $12k. He's re-habbing some mechanicals like the radiator needed to be rebuilt. And paint was shot.
He's upgrading all of the electronics too. He's going to wrap his.
This one had 600W of solar and I could off-grid without the generator too. I just couldn't run an AC unit. Inverter was too small.

Good luck again,
Doug

 

[MisterSandals]

It is my understanding that it is not feasible to install enough solar/batteries to run the appliances in an RV, certainly not the AC?

This can all be worked out ahead of time. If you can determine your energy needs, its fairly easy to determine how many panels and batteries you need.
Basing your decision on whether the vehicle is called an RV or skoolie is not very accurate in determining energy usage/needs.