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Need Advise on First Solar Power System for Conversion Van

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A bit of background:
I am converting my 1998 Astro van and I've spent every Friday, Saturday, and Sunday for the last 3 months building the inside.

I found Will Prowse's "DIY 400 Watt 12 volt Solar Power System Beginner Tutorial: Great for RV's and Vans! *Part 1*" and Part 2 on Youtube. Links for Part 1 and 2 below:

Part 1:

Part 2:

This is a perfect setup for me, my van's roof can hold 4, 100 watt solar panels maximum. I plan on living in this van for the next few years using appliances such as a heater, laptop, cell phone, blender, pressure cooker crock pot, portable fridge and others. Biggest draws will be from heater and crock pot having 1500 watts per hour draw each. The fridge is a max 45 watts per hour while cooling so the same as a laptop. It also has eco mode when not needing to cool, (5 watts per hour I think). I'd only use the crock pot for a max of 35 mins a day while the heater would only be used in winter. Of course, the crock pot puts out heat and with such a tiny living space anyways, I imagine it would warm up the area enough during winter and I wouldn't need to run the heater 100% of the time due to the small living space. I also insulated the van to keep heat out during the summer and keep heat in during the winter.

Area of living is Arizona, Utah, New Mexico, Nevada kind of area. So lots of sun!


Set up Idea:
A) 4, 100 watt solar panels in parallel (I don't plan on being 100% in the sun all the time, I will be camping under trees and such often so I want them to still work if one panel is in the shade while the other three aren't).

B) 2, 100 Ah 12 Volt batteries. Set up in series. I'm thinking of pre-ordering two SOK 100 Ah batteries. They restock on Dec. 15.

C) Everything else as outlined in the video such as MPPT, Circuit Breaker, and 2000 watt Pure Wave Sign Inverter. I have a question about the fuse block, see below.


Now to my questions:
1. In the video he uses a fuse block for DC appliances. I will only have AC appliances (everything has the two or three prong plug in and I plan on plugging in a power surge protector to the inverter). Do I still need the fuse block? If not this would save me $50+ bucks. If I don't need it why install it kind of thinking.

2. Is it okay to plug a surge protector into an inverter running multiple appliances (up to the watt capacity of the inverter of course) at the same time?!?!

3. I'm hoping to have a job in Utah but the thing with this job is the work schedule. I would be working 9.5 days straight in the wilderness with troubled youth with 11.5 days off. During those 9.5 days in the wilderness, the temperatures can vary depending on the season. Going from around the 30 degrees mark in winter to the 90 degrees area in summer. Question: Is it okay to keep my lithium batteries in this temp while not in use? During my 11.5 days off they of course would be used but the temp of the van would be more regulated in the winter. During the summer I won't have any AC. For the last two years in my apartment the temp was over 100 degrees so I personally don't need/want AC. The batteries would still be in 90 degree or more temps though. Is this okay for the longevity of the battery?

Even if I don't get the job, I still plan on moving into the van while I look for work. So this is a good thing to know anyways.


These are the main questions I have for the moment.
 
The 400W system is a good system. However, your uses might need to be addressed.

An electric heater isn’t a good match for that system imho. Not enough battery or solar for the demand. The following are more than enough heat for a van or small/medium RV and solves that power need:
The BTUs are 5-10 times what you’ll get out of an electric heater and make daily life much less of a dread- instant heat instead of hours to warm up.

Having propane on board enables this for cooking as well

Doing some 12V allows use of inexpensive RV lighting fixtures and laptops, cell phones, and other items can be charged with 12V. An RV 12V vent fan will help in summer heat by keeping it more ambient than the temperature gain in a vehicle would be.
Some small ‘dorm’ refrigerators use only 60 watts but it sounds like you’ve handled that.
Those are my thoughts. Consider them or not according to your own preferences.
 
A bit of background:
I am converting my 1998 Astro van and I've spent every Friday, Saturday, and Sunday for the last 3 months building the inside.

I found Will Prowse's "DIY 400 Watt 12 volt Solar Power System Beginner Tutorial: Great for RV's and Vans! *Part 1*" and Part 2 on Youtube. Links for Part 1 and 2 below:

Part 1:

Part 2:

This is a perfect setup for me, my van's roof can hold 4, 100 watt solar panels maximum. I plan on living in this van for the next few years using appliances such as a heater, laptop, cell phone, blender, pressure cooker crock pot, portable fridge and others. Biggest draws will be from heater and crock pot having 1500 watts per hour draw each. The fridge is a max 45 watts per hour while cooling so the same as a laptop. It also has eco mode when not needing to cool, (5 watts per hour I think). I'd only use the crock pot for a max of 35 mins a day while the heater would only be used in winter. Of course, the crock pot puts out heat and with such a tiny living space anyways, I imagine it would warm up the area enough during winter and I wouldn't need to run the heater 100% of the time due to the small living space. I also insulated the van to keep heat out during the summer and keep heat in during the winter.

Area of living is Arizona, Utah, New Mexico, Nevada kind of area. So lots of sun!


Set up Idea:
A) 4, 100 watt solar panels in parallel (I don't plan on being 100% in the sun all the time, I will be camping under trees and such often so I want them to still work if one panel is in the shade while the other three aren't).

B) 2, 100 Ah 12 Volt batteries. Set up in series. I'm thinking of pre-ordering two SOK 100 Ah batteries. They restock on Dec. 15.

C) Everything else as outlined in the video such as MPPT, Circuit Breaker, and 2000 watt Pure Wave Sign Inverter. I have a question about the fuse block, see below.


Now to my questions:
1. In the video he uses a fuse block for DC appliances. I will only have AC appliances (everything has the two or three prong plug in and I plan on plugging in a power surge protector to the inverter). Do I still need the fuse block? If not this would save me $50+ bucks. If I don't need it why install it kind of thinking.

2. Is it okay to plug a surge protector into an inverter running multiple appliances (up to the watt capacity of the inverter of course) at the same time?!?!

3. I'm hoping to have a job in Utah but the thing with this job is the work schedule. I would be working 9.5 days straight in the wilderness with troubled youth with 11.5 days off. During those 9.5 days in the wilderness, the temperatures can vary depending on the season. Going from around the 30 degrees mark in winter to the 90 degrees area in summer. Question: Is it okay to keep my lithium batteries in this temp while not in use? During my 11.5 days off they of course would be used but the temp of the van would be more regulated in the winter. During the summer I won't have any AC. For the last two years in my apartment the temp was over 100 degrees so I personally don't need/want AC. The batteries would still be in 90 degree or more temps though. Is this okay for the longevity of the battery?

Even if I don't get the job, I still plan on moving into the van while I look for work. So this is a good thing to know anyways.


These are the main questions I have for the moment.
Even though it's a small space to heat, using an electric heater will murder your batteries. One night you'll fall asleep and forget to shut it off and your batteries will not be happy. I'm in the trucking industry, maybe you could mount a 5 or 10 gallon diesel tank and have it supply a webasto or espar air heater,..they are very, very efficient, burning as little as 3 oz per hour. Also a nice dry heat and quiet as well.
 
Forgot about diesel heaters
The only thing about them is 15A 12V startup and 3A running so not much different than an RV furnace. But a lot smaller!
 
Forgot about diesel heaters
The only thing about them is 15A 12V startup and 3A running so not much different than an RV furnace. But a lot smaller!
That draw is correct, and the small size is like a semi cab sleeper for you. I never used an RV gas heater, but I do know that you can dial the diesels down to a minimum after start up.. I have 4 deep cycle RV batteries (group 29's from Walmart) in 12v that I use for the system in my semi (separate from the starter batteries). My Espar block heater pulls down from 12.8 to 12.3 on startup and then levels at 12.6 while it heats up my engine for under 40 degree start ups. I run it for up to 2 hrs depending on how close to 0 it is out. I also use an Olympic propane catalyst heater for inside heat (no electric draw at all, but very moist air).
 
Even though it's a small space to heat, using an electric heater will murder your batteries. One night you'll fall asleep and forget to shut it off and your batteries will not be happy. I'm in the trucking industry, maybe you could mount a 5 or 10 gallon diesel tank and have it supply a webasto or espar air heater,..they are very, very efficient, burning as little as 3 oz per hour. Also a nice dry heat and quiet as well.
The electric heater has a temp setting on it. It turns off when it hits the temperature I set it at and it also turns off if it tips over! I'll have to test it out and see if it is a problem but because of the small space and temp setting I want to try this before I look into installing a 5 to 10 gal tank to use for heat. I have very limited room too so this may not be a great option.
 
have very limited room too so this may not be a great option.
The diesel heaters are available in tiny footprints and come with exhaust parts, wiring, and fuel tank. Many are 6”x6”x15” total. The running watts is like 40watts.

A basic electric heater with 60% less BTUs (BTUs is heat output essentially) is going to use 50-60+ Amps at 12V. Like 750 watts. Basically 20-30 mins per acid battery…

Those aren’t scientific real numbers - they are actually practical numbers with an assumption of what you might need for heat to show you how impractical heating with electric under a small solar power system is. Not dissing you, just trying to explain this in an understandable abbreviated way with very few words.
 
The 400W system is a good system. However, your uses might need to be addressed.

An electric heater isn’t a good match for that system imho. Not enough battery or solar for the demand. The following are more than enough heat for a van or small/medium RV and solves that power need:
The BTUs are 5-10 times what you’ll get out of an electric heater and make daily life much less of a dread- instant heat instead of hours to warm up.

Having propane on board enables this for cooking as well

Doing some 12V allows use of inexpensive RV lighting fixtures and laptops, cell phones, and other items can be charged with 12V. An RV 12V vent fan will help in summer heat by keeping it more ambient than the temperature gain in a vehicle would be.
Some small ‘dorm’ refrigerators use only 60 watts but it sounds like you’ve handled that.
Those are my thoughts. Consider them or not according to your own preferences.

Of course I have to test all of this but I don't think I will keep the heater on all night anyways. I insulated the van so it does keep heat well. I'm thinking I will use it in the morning to get the cold out of the air. During the night I will be sleeping on a mattress with a -32 degree sleeping bag, a lot of blankets, and thermals if needed.

The current heater should work fine with some testing and if not then I'll look into other options if I have the budget.
 
The diesel heaters are available in tiny footprints and come with exhaust parts, wiring, and fuel tank. Many are 6”x6”x15” total. The running watts is like 40watts.

A basic electric heater with 60% less BTUs (BTUs is heat output essentially) is going to use 50-60+ Amps at 12V. Like 750 watts. Basically 20-30 mins per acid battery…

Those aren’t scientific real numbers - they are actually practical numbers with an assumption of what you might need for heat to show you how impractical heating with electric under a small solar power system is. Not dissing you, just trying to explain this in an understandable abbreviated way with very few words.
No I appreciate you trying to help. I don't plan on having the heater run through the night. Only in the morning to get the cold out of the air. At that time the sun will be coming up so I will have some power coming in. Plus the area I'm heating is only around 30 square feet so I won't need the heater for very long. Just a few minutes each day.

If my needs become greater than what I can output then I will 100% keep your recommendation in mind! Thanks for the advice!
 
No I appreciate you trying to help. I don't plan on having the heater run through the night. Only in the morning to get the cold out of the air. At that time the sun will be coming up so I will have some power coming in. Plus the area I'm heating is only around 30 square feet so I won't need the heater for very long. Just a few minutes each day.

If my needs become greater than what I can output then I will 100% keep your recommendation in mind! Thanks for the advice!
I do the same, I don't even turn on my heater until it's in the 30's outside. I use a diesel block heater and anti-gel in my fuel for cold starts down to 0. I also use a 12v electric blanket sometimes (in the 40's, it's too hot in the 50's), this is very efficient as well. If I plug it in at night while my batteries are at 12.8, the number is never under 12.6 in the morning, but that's with 4 deep cycle batteries.
 
don't plan on having the heater run through the night. Only in the morning to get the cold out of the air. At that time the sun will be coming up so I will have some power coming in.
Well try it! You’ll know if it doesn’t work.

My tolerance for low temperature is admittedly low. Raynaud Syndrome is one factor. Average body temp for me is 97.7 or 97.8…

Anyways, I have water lines and a shower I can’t let freeze so my perspective is different. (11*F at sunup today, too) Plus the moisture if i don’t maintain 45+ overnight, and taking a shower makes everything wet and I’m not a fan of mold.

Your van and your tolerance may be different than my situation. And/or your low temps might not be as bad. I stayed a few weekends last winter and my pillow got soaked with condensation from my breath if it was below 40. No tolerance for that!
 
I do the same, I don't even turn on my heater until it's in the 30's outside. I use a diesel block heater and anti-gel in my fuel for cold starts down to 0. I also use a 12v electric blanket sometimes (in the 40's, it's too hot in the 50's), this is very efficient as well. If I plug it in at night while my batteries are at 12.8, the number is never under 12.6 in the morning, but that's with 4 deep cycle batteries.
I was just looking at my electric heating pad last night. Rated for 30 watts! I'd be able to run that all night if I wanted to! For 8 hours of sleep that is only 240 watts.

I doubt I will ever get around 0 degrees at night. I plan on staying in Arizona, New Mexico and that kind of area. When I googled the climate for Arizona I saw it is around mid forties at night in winter. Obviously this is an approximation and will change from year to year but they base climate on 30 years of data so it should be reliable (ish).
 
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Well try it! You’ll know if it doesn’t work.

My tolerance for low temperature is admittedly low. Raynaud Syndrome is one factor. Average body temp for me is 97.7 or 97.8…

Anyways, I have water lines and a shower I can’t let freeze so my perspective is different. (11*F at sunup today, too) Plus the moisture if i don’t maintain 45+ overnight, and taking a shower makes everything wet and I’m not a fan of mold.

Your van and your tolerance may be different than my situation. And/or your low temps might not be as bad. I stayed a few weekends last winter and my pillow got soaked with condensation from my breath if it was below 40. No tolerance for that!
I enjoy the cold. Most of the time... and I can see your perspective on why you'd want you and your van heated well all night. I don't have a shower system but a hand pump faucet. I will have to make sure they aren't holding water each night.

Temps should get around 30. Depending on the state I find myself in. I've tent camped in that temp before with a pad that wouldn't hold air most of the night. I was snuggly warm though. Of course, I was using a 0 degree sleeping bag, lightweight thermals, clothes and a blanket. Afterwards, I got smart and ordered a fleece insert for my bag and heavyweight thermals. Bag and insert is rated for -32 degree now.
 
My experience is that I spend three months a year traveling and living in my van, a 1982 Vanagon. I have 400 watts of solar and a 280 amp hour lithium battery. They do a pretty good job of keeping up with my solar needs, because I don't have a crock pot, electric heater or other appliances. i have a Truckfridge, a laptop, LED lights and a radio. Heat is via a diesel heater, one of my best investments.

Your system is never going to keep up with what you have listed as loads, unless you're driving every day and recharging via the alternator.

IMHO you're making the same mistake I see most people make when starting out, trying to recreate their house in their van, and trying to carry everything they have with them. My advice, for what it's worth, but based on years of travel all over the US, Mexico and Central America in vans, is to very carefully consider every single pound that goes into your rig. Each of them adds to the load on the suspension, load on the motor, decreased mileage, wear and tear, less ground clearance and so forth. Many of the broken down rigs, blown motors and other problems I've seen along the way have been the result of overloaded rigs. Over time, many people migrate to smaller vehicles and less "stuff", it simplifies life considerably.

Of course if you're just going to be driving from RV park to RV park and plugging into shore power that's another story, I spend weeks at a time camping 50 miles down dead end dirt roads in the desert, my considerations may be different from yours.

Good luck with your project, but tuck some of this into the back of your memory for some point in the future.
 
I’m half-way through converting a 2016 Transit Connect cargo van. Started by buying battery, 24v Victron 100/20, and some gizmos due to an extreme number of videos. See how other van lifers have done their builds. Most diesel heaters are too powerful for small vans. Mine is 2KW and my van will not be insulated. Think in cubic feet instead of the square feet of the marketing idiots. I don’t think you need to worry about your days off - most hospitals are air conditioned, lol.
 
Hi, you mentioned operating in environmental temperatures of 90F how did your experiences there go? Thanks!
 
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