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Old 09-13-2021, 12:30 PM   #1
Mini-Skoolie
 
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Help powering a skoolie.

Ok. I am looking to build our first Skoolie. My wife is onboard and excited about it, but she has a long list of wants/"needs". It will take a lot of power.

Her list includes:
2 mini splits with heat
Tankless water heater
Full size refrigerator
Microwave
2 Televisions
2 Blu-ray players
A laptop
Wi-Fi
A couple of fans
Exterior lighting

I will also need to power
Water pump
Assorted LED lights
Electrical outlet for cooking appliances (can be the same as microwave)
Various outlets for phone charges and what not.

She also wants to be able to boondock. I figure the best route would be solar. I have a 1997 International 3800 Bluebird 39' dog nose. I can fit 8 bifacial 435W panels on the roof. That will give me close to 3500W. Now I need to use that power. I live in Texas so the ACs would run almost 24/7.

I need help designing a system that has enough batteries to run everything over night. I would also like to be able to charge the batteries while driving from the alternator. And the ability to hook up a generator or shore power. I am fine with using the same outlet for the shore power and generator.

I like the idea of LiFePo4 batteries, but I also do have a budget to be mindful about. The solar panels will be $2100. I would like to stay under $10k for everything, ie panels, batteries, chargers, inverters, wiring etc. Is it possible?

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Old 09-13-2021, 03:29 PM   #2
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Quote:
Originally Posted by UpShinnCreek View Post
Ok. I am looking to build our first Skoolie. My wife is onboard and excited about it, but she has a long list of wants/"needs". It will take a lot of power.

Her list includes:





Electrical outlet for cooking appliances (can be the same as microwave)
Various outlets for phone charges and what not.

She also wants to be able to boondock. I figure the best route would be solar. I have a 1997 International 3800 Bluebird 39' dog nose. I can fit 8 bifacial 435W panels on the roof. That will give me close to 3500W. Now I need to use that power. I live in Texas so the ACs would run almost 24/7.

I need help designing a system that has enough batteries to run everything over night. I would also like to be able to charge the batteries while driving from the alternator. And the ability to hook up a generator or shore power. I am fine with using the same outlet for the shore power and generator.

I like the idea of LiFePo4 batteries, but I also do have a budget to be mindful about. The solar panels will be $2100. I would like to stay under $10k for everything, ie panels, batteries, chargers, inverters, wiring etc. Is it possible?

Your list is pretty close to the list I was given by my gal including the dual mini splits.
All is not lost and it's doable though you may need some alternative charging when the panels can't get enough sun. That just depends on the entire house you're building and other infrastructure.


9,000 BTU mini splits can be had for under 800 watts each
Run the tankless water heater on propane
The fridge is about 900-1000 watts per 24 hours

(that's our fullsize in the house use read with a kill a watt meter)
Electric cooking can be a BIG power hog depending on what kind of, &

how much, and how often there is cooking.

The microwave, televisions, Blu-ray, etc. are intermittent use & small

overall draws. NOTE though that USB chargers are a constant draw

if powered as there is a transformer to bring 110VAC to 5VDC or a

converter to bring DC to 5VDC. Those devices draw power even

when no device is plugged in.



I will try to attach my calculation spreadsheet though it will likely just be a pic of it.
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Old 09-13-2021, 03:40 PM   #3
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Well couldn't get even a couple lines to copy in as text I suppose I'll eventually put it up on the HamSkoolie web site but it's not there right now.
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Old 09-13-2021, 11:47 PM   #4
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I need to get a kill-a-watt. I haven't bought anything yet because I don't know if it will all fit. I am hesitant on running propane because I will already need diesel for the bus, and gasoline for the generator. Yes, I could buy a diesel generator, or even a propane one, but I already have 2 9000w generators, 2 3500 watt generators, and a 2000w inverter generator. I don't want to have to another. Ultimately, I want to only have to worry about enough fuel to get to the destination and back, not have to worry about it while I am there as well.

And my wife just threw me another curve ball tonight. I mentioned that it may be hard to power everything she wants, and even harder on overcast or stormy days. Now she wants to add a couple of wind turbines to mount to a pole on the roof when we are parked to help counter act the lack of solar. I will admit that it isn't a bad idea, but it will male figuring out how to make it all work even hard.

So now I need to know what I need to be able to convert roughly 3500W of solar panels to an unknow size battery bank. And then find an inverter big enough to power every thing, and then incorpate the ability to have the alternator charge the batteries (and the solar panels to charge the bus battery), the ability to hook up shore power or a generator, and power from wind turbines.
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Old 09-14-2021, 07:20 AM   #5
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I don't know what yall's ability to just kiinda roll with it is, but if you're planning on living full time and traveling (vs. being stationary long term) then I don't know that bus life is practical for you. Reason I say this is because we know a couple who had similar comfort needs and...things didn't work out like they'd hoped. They spent ALL of their time in RV parks instead of off-grid like they'd wanted to and they found it to be too much like living in a trailer park instead of in the great outdoors. They spent a lot of time and money building up their rig and were absolutely miserable in the end. Actually, they weren't on the same page...which was the real problem. She was miserable with the lack of comfort, and he could have lived without all of the comforts (washing machine, AC, etc.) and so would have been fine boondocking. I don't know what ever became of them, but I know they weren't happy with the situation.

I don't want to assume what your priorities/personalities/relationship are but just wanted to give you a sort of cautionary tale. The more resilient you are (and yes, the less you need to shower regularly!) the easier full time bus life will be. It would be wise to do a gut-check before you get too far along, and IMO it would be a great idea for both of you to do the build so you can both have an idea of the capabilities of the bus and yourselves.
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Old 09-14-2021, 01:11 PM   #6
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What Drew Bru said...

Assuming you're still going forward on your conversion, hopefully other electrical gurus on here will be jumping in to offer you options on hardware for you and your wife's power requirements and budget #'s...

If money is no object, you can get all of the comforts of home built into a skoolie.
The sky is really the limit when the gloves come off and the skids are greased with $$$.

Things can also happen on a budget, but it will take longer to get where you might want to be in the project.

Good luck, and post up any progress or pics of your project as you go...
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Old 09-14-2021, 02:27 PM   #7
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Quote:
Originally Posted by UpShinnCreek View Post
I like the idea of LiFePo4 batteries, but I also do have a budget to be mindful about. The solar panels will be $2100. I would like to stay under $10k for everything, ie panels, batteries, chargers, inverters, wiring etc. Is it possible?
Here's how I would approach your question.

3500 watts is a lot of solar, and a lot of power to push into batteries. You'll need a charge controller (many out there, figure $200-350). For the battery you need a BMS (get a programmable configurable one, like a BMS-250A from Daly or equivalent, about $200); a Smartshunt (Victron is pretty good, about $150).

Regarding amount of battery storage, it's really dependent on your power budget. Normally you look at power needs, then size the battery bank and solar system accordingly. In this case you're saying you have the solar and so let's assume that's what you need.

With that much solar you can push almost 300 amps an hour into storage. You get almost 8 hours of pure sunshine a day (on average), so that's 2,300 amps a day you could store. Some days none, some days more, but 2.3K amps. Let's derate that number a bit, say, by a third, just to be conservative. That means you can safely assume you'll get fifteen hundred amp-hours of energy each day-that's on average. But four out of ten days you won't get that much, so you need to account for cloudy days. Let's add 40% to the battery bank. You'll need about 2,200 amp hours of storage to cover the cloudy days as well. LiFePo4 costs about $2.75 per amp of storage, so to take advantage of that much solar you'd need about $6,000.00 worth of batteries.

But again, you may not need all that storage when it comes right down to it. That's why you start with a power budget first, otherwise you're questioning whether a skoolie is for you without actually getting to facts that help you decide.

And if anyone takes issue with the assumptions, just change them. This is for example, to help show an approach to sizing and budgeting.

You have generators, you say. How about putting a bank of solar on, maybe putting in two 280 AH banks of batteries, and cover the rest with a genny until you understand how much juice you actually need?

Conversely, boondocking is by definition 'hanging out in the wild' so why all the power needs? Others have written very nice posts on how to rethink the whole 'let's replicate our first world living space in a mobile platform'. Maybe this is the inflection point in your life where you decide to do it differently.

P.S. Others here have lots more knowledge of solar sizing and may be able to refine the approach, or add other suggestions.

P.P.S. Wind turbines are for farms, not skoolies.
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Old 09-14-2021, 03:57 PM   #8
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Oh MY where to start?
First off, you can't talk "amps" or "amp hours" without including voltage. Alone, the number of amps tells us nothing. 200 amps at 48 volts is almost 10kWh while 200 amps at 12 volts is a minuscule 2400 watts.
WATTS are what do the work and what we need to be basing all of our planning work on.

Amps and volts do have their place and need to be understood, but initial planning should all be done using watts as they represent the amount of work that a given electrical system does.



Quote:
Originally Posted by Rucker View Post
...3500 watts is a lot of solar, and a lot of power to push into batteries.
We are planning on 2500 to 3500 watts on our skoolie. You have to remember, you're not going to get more than a few hours a day of full production without the complexity, expense, weight, and restrictions of a tracking system that automatically moves the panels in order to maintain optimal production.



Quote:
Originally Posted by Rucker View Post
...You'll need a charge controller (many out there, figure $200-350).
With a system pushing 3500 watt max I'm not aware of any trusted controllers that can be had for that price. Perhaps EACH and a minimum of two.



Quote:
Originally Posted by Rucker View Post
...For the battery you need a BMS (get a programmable configurable one, like a BMS-250A from Daly or equivalent, about $200);
It would be far better to purchase batteries with factory built in BMS.



Quote:
Originally Posted by Rucker View Post
...With that much solar you can push almost 300 amps an hour into storage. You get almost 8 hours of pure sunshine a day (on average), so that's 2,300 amps a day you could store. Some days none, some days more, but 2.3K amps. Let's derate that number a bit, say, by a third, just to be conservative.
Theoretically perhaps. Highly unlikely.

That 8 hours of sunshine is never optimally aligned with the panels unless they are tiltable and rotatable OR the bus is sitting on the equator at high noon. As such, spec'd production will almost never be met though, with reflections and such it is theoretically possible. A conservative estimate therefore would be 40 or 50% of panel rating on a clear day with no shade on any panels.


Quote:
Originally Posted by Rucker View Post
... P.P.S. Wind turbines are for farms, not skoolies.
Nothing wrong with a wind turbine if it fits the mission of the skoolie. Ours will have a deployable turbine as our mission includes a lot of time on the coast where overcast days go on for weeks but so does the wind. 400 watts of turbine production, over 24 hours (the wind doesn't stop at night) is almost 10kWh of electric....quite worth flipping up a couple of masts and mounting a couple of small turbines.


Takeaways:
Convert ALL electrical draws to watts (E = I*R & P = I*E)
Estimate ALL electrical draws as to how many hours per day
DO NOT add winter heat AND summer cooling draws, pick only the higher
Determine which draws are simultaneous
Derate your panel specs by using solar maps showing expectations
Size derated panel output to meet daytime needs and replenish batteries
Size battery bank to meet overnight needs plus your desired "excess" capacity to cover low or no (panels in shade or with snow for ex) solar days.
A small generator can be used as backup for those poor solar days as can an auxiliary alternator on the main engine, wind turbines, etc.
Plan to spend a significant amount of your build money on the solar system when A/C is a requirement.
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Old 09-14-2021, 05:53 PM   #9
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I appreciate the advice, I really do. We do not plan to live in the bus. It will get used a few weekends a year plus a week and a half trip a year. Every year for our anniversary, my wife and I go to another state and get married again. I love my wife more than anyone in the world. I would give my life to try to save her from dying. But we would end up killing each other if we are confined to a bus for extended time frames. Death would come sooner if she is hot and miserable.
My understanding is that I can add batteries and such at a later time. I just want to get the solar panels and all related wiring run in the beginning. Once electrical and plumbing is run, I can insulate and seal up the walls and ceiling. At that point, I will build a few interior walls that will complicate access to add more solar panels or run additional wiring. Additionally, I don't want to buy smaller components that I will then have to change out later.
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Old 09-14-2021, 06:15 PM   #10
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With such a mission you can probably significantly reduce fuel and electrical infrastructure.
Get a dual fuel (gasoline & propane) generator large enough to run your AC and a little more to charge the batteries. Install a 29 gallon permanent propane tank.
If the solar and batteries aren't sufficient, fire up the propane fueled generator to recharge the batteries and run the AC. You can even get an electric start generator and wire the system to automatically start it when the batteries get to a certain point.
I wouldn't suggest such a system for full time living but for weekends and an annual two week trip it would be just fine. Just know that if you want to stay in parks (which would negate the need for solar so I'm assuming NOT) they may have no generator rules or "quiet hours".
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Old 09-14-2021, 07:11 PM   #11
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Quote:
Originally Posted by HamSkoolie View Post
Oh MY where to start?
:-') Is this in relation to my post? I'm assuming yes...
Quote:
First off, you can't talk "amps" or "amp hours" without including voltage. Alone, the number of amps tells us nothing. 200 amps at 48 volts is almost 10kWh while 200 amps at 12 volts is a minuscule 2400 watts.
WATTS are what do the work and what we need to be basing all of our planning work on.
Let me clarify. I converted solar panel watts to amps assuming a 12 volt system. That makes the rest of the math around battery capacity easier. I probably should have made that clearer.
Quote:
Amps and volts do have their place and need to be understood, but initial planning should all be done using watts as they represent the amount of work that a given electrical system does.
Agreed. If you re-read my comments, this was all based on the original statement of solar panel capacity, captured in watts.

Your point that initial planning should be done based on requirements is absolutely correct-totally agreed.

Quote:
We are planning on 2500 to 3500 watts on our skoolie. You have to remember, you're not going to get more than a few hours a day of full production ...
Here's what I wrote:

You get almost 8 hours of pure sunshine a day (on average), so that's 2,300 amps a day you could store. Some days none, some days more, but 2.3K amps.

I should have been clearer that the calculations were based on 12VDC system. I checked the OPs location (Texas), looked up the average daily sun and sunshine hours, and that's where the numbers came from.
Quote:
...without the complexity, expense, weight, and restrictions of a tracking system that automatically moves the panels in order to maintain optimal production.
Search this forum. The maximum added benefit of tilt-a-whirl panels is about 25%, and that's only if you're way up North. In Texas, the benefit is minimal.

Quote:

With a system pushing 3500 watt max I'm not aware of any trusted controllers that can be had for that price. Perhaps EACH and a minimum of two.
Absolutely-great point. I think it's also good to have redundancy, so double the controllers?
Quote:
It would be far better to purchase batteries with factory built in BMS.
I disagree. The cost per amp hour of storage is wicked high for batteries with a built-in BMS. Not sure you can program them or that they do active cell balancing. If you are truly uncomfortable with building your own batteries, these are an option. But they are expensive and (I think) have significant limitations.
Quote:
Theoretically perhaps. Highly unlikely.
Chill, dude! You've missed my point, stated very clearly. I said:
And if anyone takes issue with the assumptions, just change them. This is for example, to help show an approach to sizing and budgeting

Quote:
That 8 hours of sunshine is never optimally aligned with the panels unless they are tiltable and rotatable OR the bus is sitting on the equator at high noon. As such, spec'd production will almost never be met though, with reflections and such it is theoretically possible.
This topic frequently comes up. I looked in to this a few months ago. The science supports my observation that there's not a lot of efficiency lost when panels are not perfectly aligned with the sun. The cost of tilt and swivel simply does not pay for itself, unless you live is an extreme north climate. This guy's from Texas.

Here's an article:
https://www.alternative-energy-tutor...ientation.html

Here's a link to the discussion topic in this forum:
https://www.skoolie.net/forums/f13/l...tml#post409266
Great reading.

And another:
https://www.skoolie.net/forums/f49/s...nts-35278.html

Basically, only if you're geeking out would you put that kind of investment into swivels, and even then, the mechanicals will fail before long.
Quote:
A conservative estimate therefore would be 40 or 50% of panel rating on a clear day with no shade on any panels.
Your point would be valid except I've already derated the panels by a third to account for it:

Let's derate that number a bit, say, by a third, just to be conservative. That means you can safely assume you'll get fifteen hundred amp-hours of energy each day-that's on average.

I'm hoping this makes sense. I want to make sure we're not talking about two different things.
Quote:

Nothing wrong with a wind turbine if it fits the mission of the skoolie. Ours will have a deployable turbine as our mission includes a lot of time on the coast where overcast days go on for weeks but so does the wind. 400 watts of turbine production, over 24 hours (the wind doesn't stop at night) is almost 10kWh of electric....quite worth flipping up a couple of masts and mounting a couple of small turbines.
Okay, okay, so for about five hundred bucks you can put in something that purports to generate 600 watts of power. I quote one of the reviewers on Amazon:

Well, I got .5 amps with 17 Volts, yeah, do the math. Thats 8.5 watts using a 180mph back pack leaf blower.

I'm not saying it doesn't work, I'm only saying it isn't worth the investment, at any time, for a skoolie, and probably not even in general. I'm probably biased.

I do get a kick out of all the skoolie Facebook group posts about turbines that go like this: 'how efficient are they when you're driving?'

Quote:
Takeaways:
Convert ALL electrical draws to watts (E = I*R & P = I*E)
Estimate ALL electrical draws as to how many hours per day
DO NOT add winter heat AND summer cooling draws, pick only the higher
Determine which draws are simultaneous
Derate your panel specs by using solar maps showing expectations
Size derated panel output to meet daytime needs and replenish batteries
Size battery bank to meet overnight needs plus your desired "excess" capacity to cover low or no (panels in shade or with snow for ex) solar days.
A small generator can be used as backup for those poor solar days as can an auxiliary alternator on the main engine, wind turbines, etc.
Plan to spend a significant amount of your build money on the solar system when A/C is a requirement.
I agree with all of this-all great points, and thanks for the dialogue.
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Old 09-14-2021, 08:07 PM   #12
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Here’s a podcast about The Broccoli Bus and about the electrical system in it

https://m.soundcloud.com/theoffgrids...r-conditioning
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Old 09-15-2021, 06:23 AM   #13
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The majority of the use of the bus will be on a few hundred acres I got that has no utilities. There isn't a light, let alone a house for a few miles in any direction. The original plan was to put a shipping container bunk house out there. The bus should be cheaper and can be used anywhere. Then my beautiful wife started adding her "requirements" and now I need the power of small star to run everything. But once it is finished, it will be nicer and more confortable for everyone.
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Old 09-15-2021, 09:24 AM   #14
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In that case… go to SanTan solar. Lay down, on a couple of cinder blocks, say, 8, or 16, or 32 of their 250W panels. Just facing up.

If you have such an abundance of space almost everything becomes possible.

You can buy cosmetically flawed but fully functional ones for $35 a piece. You can buy perfect ones for $50.

When you show up on your land, you just plug in your bus. You can have an absurd amount of power at your disposal for around $1000.

You can’t store the power or carry it on your skoolie, but if it is to run a cryogenic chamber for a sweaty spouse, an aluminum smelter, a Bitcoin farm, an ice cream factory or an NSA facility - you can play ball.

Seriously though. Solar panels are so absurdly cheap nowadays that it there’s no better use for acreage than cinder blocks with solar panels.
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Old 09-15-2021, 09:54 AM   #15
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Originally Posted by Danjo View Post
Here’s a podcast about The Broccoli Bus and about the electrical system in it

https://m.soundcloud.com/theoffgrids...r-conditioning
Very good reference videos. Worth reviewing, especially newbies..
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Old 09-18-2021, 03:23 PM   #16
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Get Will Prowse book

“DIY Solar Power Made Easy “ saved my sanity. His YT channel is excellent too…
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Old 09-18-2021, 07:59 PM   #17
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Quote:
Originally Posted by Rucker View Post
:-') Let me clarify. I converted solar panel watts to amps assuming a 12 volt system.
Yes it could have been more clear that you were using a standard 12 volts but I still don't think your math works.
3500 watts of solar, at 12 volts, does indeed come out to almost 300 amps but the but that is theoretical maximum which only exists on paper. It assumes the sun is directly perpendicular to the panel (only happens on the equator or with "tilt a whirls"), the panel is perfectly clean, and there is no obfuscation in the atmosphere. With flat mounted panels there is zero opportunity to meet any of these requirements unless sitting directly on the equator.
While you de-rated the panel output, you didn't de-rate sufficiently to account to all the factors mentioned above. While the period of astronomical noon +/- and hour might need be de-rated only 20 or 30% due to angular inefficiency, dirt, atmospheric conditions, etc. the rest of the light available is going to be converted far at far closer to 40 or 50% efficiency thus requiring a 50 or 60% de-rating.


Quote:
Originally Posted by Rucker View Post
You get almost 8 hours of pure sunshine a day (on average), so that's 2,300 amps a day you could store. Some days none, some days more, but 2.3K amps.
So, I plugged in Austin Texas to a PV calculator with the following system parameters:
12 VDC panels, 3,500 watt panel output, flat mounted (0 tilt), 14% system losses and 96% inverter efficiency.
The total ANNUAL kWh is only 4,702.
The highest month output is July 533 kWh for the MONTH which is 17.2 kWh per day. In December the output is 7.45kWh per day.

Quote:
Originally Posted by Rucker View Post
Search this forum. The maximum added benefit of tilt-a-whirl panels is about 25%, and that's only if you're way up North. In Texas, the benefit is minimal.
Totally agree. Human nature what it is, very few people with a manual tilt system are going to employ it let alone keep adjusting it to get maximum benefit. In super high latitudes a manual tilt can be quite effective as the sun never gets high. Heck in Alaska the sun never gets high enough to rise for how long each year? Since we're wanting to enjoy Alaska and Canada but I know I'm not going to tilt things, we'll just be buying more generator fuel when our driving doesn't recharge the house batteries (via second dedicated alternator).

Quote:
Originally Posted by Rucker View Post
I disagree. The cost per amp hour of storage is wicked high for batteries with a built-in BMS. Not sure you can program them or that they do active cell balancing. If you are truly uncomfortable with building your own batteries, these are an option. But they are expensive and (I think) have significant limitations.
I'm not sure I can agree there. While I was initially planning for 1/2 of a Nissan leaf reconfigured and with a BMS installed, INSURANCE is an issue. We met a skoolie couple on the road. After a direct strike by lightening their electrical system fried and the batteries started a fire. This wouldn't be unusual for ANY battery with a lot of juice after a direct strike but because they built up their own battery, the insurance denied their claim.
So if you can't afford to lose everything in your skoolie and take the financial hit, batteries need to be factory items.
I am not going to divulge the source (until we get ours) but there is a current battery on the market with 5.1 kWh of lithium, built in BMS and circuit breaker as well as com provisions for remote monitoring that is just $1500. In a 12 VDC system that's 425ah and $3.53 per amp hour....for a battery with warranty and the all important financial protection over home built.

It's also insanely compact at 100 pounds, and has great reviews. We're going with two.
Four Battleborns @ $800ea (I think they're 900-1000) would bring only 4.8kW at a cost of $3200.
Of course there's shipping unless you can pick them up yourself.

Quote:
Originally Posted by Rucker View Post
Chill, dude! You've missed my point, stated very clearly. I said:
And if anyone takes issue with the assumptions, just change them. This is for example, to help show an approach to sizing and budgeting
I'm chill, just having some mathematical and engineering type discussion. Nothing personal, just discussing the topic. At least on this end, I think you brought up good points as well.

Quote:
Originally Posted by Rucker View Post
Okay, okay, so for about five hundred bucks you can put in something that purports to generate 600 watts of power. I quote one of the reviewers on Amazon:
Well, I got .5 amps with 17 Volts, yeah, do the math. Thats 8.5 watts using a 180mph back pack leaf blower.
I'm not saying it doesn't work, I'm only saying it isn't worth the investment, at any time, for a skoolie, and probably not even in general. I'm probably biased.
I do get a kick out of all the skoolie Facebook group posts about turbines that go like this: 'how efficient are they when you're driving?'
I think you're right about bias. And that's fine we all have them, the difference is whether we realize it.
Turbines aren't for everyone but here's why we're going to eventually have one or two in our build and so we're planning that from the start so the infrastructure is there. On the coast in Oregon, there is almost always a lot of wind but the sun is an elusive creature, sometimes for weeks upon weeks.

The typical wind speed on the coast where we go is sufficient to drive a 400W turbine to it's 400W production speed. Since the wind blows 24/7 that comes out to 9.6kW, even if it only produces 3kW, that's probably sufficient for our needs on the coast as electrical needs there are minuscule.

As for the 180 mph leaf blower only getting the turbine to produce 8.5W, that 180mph marketing point is at the exit and dissipates rapidly. It's also not going to apply that "wind" to the entire turbine blade surface, and so I wouldn't expect it to produce much of anything other than damage to the turbine. Now a WIND TUNNEL that had a mass of air sufficient to impact the entire blade disk, that would do, so long as it was of sufficient diameter to avoid creating a "shroud" effect.
And OH YES, the folks that think running a turbine, alternator, wheel on the ground, etc. for "free energy"..... I don't think they ever rode a bicycle with a mechanical generator for the lights which flipped over against the tire when needed. Even those little guys you could tell were dragging and making you work harder.


Hope what I've written makes sense, particularly the PV calcs for Texas.
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YouTube: HAMSkoolie WEB: HAMSkoolie.com
We've done so much, for so long, with so little, we now do the impossible, overnight, with nothing. US Marines -- 6531, 3521. . . .Ret ASE brakes & elect. Ret (auto and aviation mech). Extra Class HAM, NAUI/PADI OpenWater diver
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Old 09-18-2021, 09:11 PM   #18
Bus Nut
 
Join Date: Jun 2021
Location: Baja often, Oregon frequently
Posts: 427
Year: 1996
Coachwork: Our hot little grubbies...
Chassis: Ford CF8000 ExpeditionVehicle
Engine: Cummins 505ci mechanical
Rated Cap: Five Heelers
Quote:
Originally Posted by UpShinnCreek View Post
[ edited for brevity ]
...our first Skoolie. My wife...has...wants/"needs"...Her list includes...She also wants...
.
a -- I am interested in the camping and boondocking hx of your spouse.
.
b --I get the impression -- I could be way off-base here, so correct me if I am wrong -- your spouse wants/"needs" you to re-create a stand-still house inside a 7x24 space?
These big expectations might require tiny appliances, tiny furniture, but a yuge budget of time and materials.
.
c -- A contrarian view:
2003, my Very Significant Other got sick.
We immediately crafted our RequirementsStatement.
It included Traveling! Now! instead of months/years perfecting the conversion.
.
Following our RequirementsStatement:
Within a week of diagnosis, we acquired a 1997 Ford CF8000 commercial truck to convert to our concept of an ExpeditionVehicle.
Within a week -- while selling everything -- we completed our basic conversion and hit the road.
.
Our basic conversion serves us well going into nearly two decades.
As we travel, our interior evolves... I use the term 'organically'.
.
As we travel -- one-hundred percent boondocking -- we realize all those 'must-haves' on our original RequirementsStatement were fluff, meaningless material way-points to impress people ("...people we don't know and probably despise...", as the saying goes).
.
For our 2003 ExpeditionVehicle, we built on a foundation of decades of full-time live-aboard, plus a couple years experience delivering RecreationVehicles manufacturer-to-dealer and dealer-to-shows... convincing us of one powerful point -- SIMPLER IS BETTER.
.
d -- A suggestion:
Instead of starting with a massive array with enormously complicated components cobbled into enormously complicated systems, could you two experiment with just a weekend boondocking in your rig as-is to see how it goes?
Toss in the usual car-camping gear... and go?
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Old 09-18-2021, 09:22 PM   #19
Mini-Skoolie
 
Join Date: Aug 2021
Location: Texas
Posts: 20
Year: 1997
Coachwork: International Bluebird
Chassis: 3800
Engine: DT466E
Rated Cap: 71
Just to clarify, I do not have any intentions of running the wind turbines while driving down the road. I was just thinking I could mount them on a 10ish foot pole, have them fit into a socket that is mounted to the roof, and have some guy wires that attach to premounted anchor points on the roof to further secure the pole.
I know I can't have a roof top deck, so I am trying to fill the roof with solar. I know my wife is going to come up with more "must haves" so I am going for as big as I can. And who knows, I may use it as a man cave when we are not out in it.
I am trying to figure out all of my roof penetrations now so I can get them in and leak checks before insulation and painting the roof top. Everything else can be worked out later since it shouldn't involve going through the roof.
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Old 09-24-2021, 06:19 AM   #20
Mini-Skoolie
 
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Join Date: Jul 2018
Location: The Adirondacks
Posts: 20
Year: 03
Chassis: BlueBird
Engine: 5.9 Cummins 24v
anyone designing a system, seriously needs to consider lithium compound batteries.
There is no comparison between AGM/flooded lead acid!
If you are looking for the long haul, it's a no brainier, even though the initial cost is higher.
When using huge solar arrays (relatively), lithium, when set up with proper BMS, can take all you can throw at it. Handy for us northern folks who get 2-5 hours of sun a day ( or week, sometimes !) It's nice to be able to harness every drop of solar power produced.
Another issue is discharge- lead batteries can only be discharged 50% or you seriously derate their charge/ discharge cyles.
That is a HUGE consideration when comparing the technologies.

Someone mentioned Will's book, while I have not read it, I have watched his yt videos and it's a great place to start.
If I were only concerned about a weekend here and there and 2 weeks in summer, my Honda would be doing the lions share of the lifting. Gas is expensive, BUT...Honda's last longer than dirt.

I wasn't aware of insurance not covering user installed systems, guess I better look at the fine print, but who to say WHICH factory installed the system? My unit was completely custom- ????
Are you trying to say if you are a second battery to your pickup truck, and it was hit by lightning and burned up, your insurance wouldn't pay because it was not factory installed? I think you need a new carrier...

Take Care and 73 (HAMSKOOLIE)
Dean (Bigdaadio/K2WW)
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