Looking to go solar and would appreciate some input

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My laptop takes 19.5 volts DC to charge at about 60 watts IIRC (same charger works on my i7 desktop). I have never plugged it into an inverter to charge. I bought a car charger for my make and model laptop. I don't get the dual conversion loss of going from 12VDC to 120VAC and then back to 19.5 VDC. Just one conversion from 12VDC to 19.5VDC. I have an inverter and can count the number of times I have used it, 0. Thought I might need it but never have.

I have 2 - 100 watt flexible panels industrial velcroed to my roof and 2 more as portables that can be connected in parallel to my existing fixed ones. Can't bend them much though as you can crack the cells. Be very careful with flexibles as portable.
 
Thanks for the information Brian.  I assumed that there were downsides to using flexible solar panels as portables even though the companies selling them lead you to believe that they are indestructible.
 
You are never going to be able to power your tv and furnace blower off a small system.Go big.You can never have too much power.
 
They ARE pretty tough. I don't flex mine much at all though and usually carry them by a corner so they hang down. I do have to flex the portables a little to get them out of my basement but hasn't been an issue so far. I do not walk on the either. The ease of mounting on the roof (no holes) is what really sold me on them. I do have them spaced up off the roof with the packing material cut into small squares so there is some airflow underneath.
 
nature lover said:
Don't take this for gospel - I am not a tech guy.  I have charged my laptop battery with one of those cheap cig plug inverters.  I think I was told that I could charge it that way when the unit is off but not while it is up and running.  One of you folks that knows about these things please let me know if that is right.
I have a cheap inverter that fits in a cup holder and my laptop runs off it all the time even when on. You see I use my laptop as GPS using Delorme Street Atlas USA so my laptop is on all the time when I am traveling.
 
Travlndude said:
I use my laptop as GPS using Delorme Street Atlas USA so my laptop is on all the time when I am traveling.

Ah ha. Nice big screen. My old Garmin is tiny.
 
Hello again everyone.

It has been quite the roller coaster ride of research, etc. over the past few week, but I finally decided what I was going to do about my auxiliary power needs for the van.  And, to be honest, I am still wondering if I did the right thing, but it finally came down to making a decision and moving forward.  So, with all that in mind, here is what I have done.

I still felt like I wanted a portable solar system for now.  I like that it is basically plug and play and that you have the flexibility of putting it where you can get the best benefit of the sun rays.  That being said, I went with the Renogy 100 Watt Eclipse folding solar system.  https://www.renogy.com/100-watt-eclipse-monocrystalline-solar-suitcase/.  And since they were offering these up on ebay as a "Make An Offer" post I was able to knock some off of the price.   The other deciding factor was that I am unsure of what I want to do with the roof of the van in the future such as putting in a fantastic fan, etc.  I also do not have access to help installing a permanent setup right now and cannot physically do it.

Because of the minimal needs I went with the Cobra 400 Watt Inverter based upon several people's opinions including Bobs.  I was also fortunate enough to find a deal on these as well online.

I have not ordered my batteries yet, but am close.  This has actually been the hardest decision in all this between the cost of them and also the very limited space that I have in my built-out Chevy Astro (I did my own buildout last summer).  I am going to go with an agm battery, but because of the very limited space that I have in the van I am going with a smaller size agm and then paralleling 2 or 3 of them to get more amp hours.
 
As we speak, I am also getting some cables custom made.  I wanted to have ring terminals on both ends of the cables so that I could do a permanent mount and the cables that are coming with the standard package have alligator clips on them.

I do have to admit that using and charging a battery inside the van does make me nervous still.  While it is stated that using agm batteries inside is safe, I have done enough research to know that they do have the risk of gassing if overcharged, although they say that the odds of this happening are small.  If anyone wants to share anything here to put my mind at ease please feel free.

Ironically, I got a call last night from a couple that I worked with as camp hosts at the Mt. Whitney Portal a few summers ago and they offered to give me their Honda 2200i generator.  It has very few hours on it and is in very good shape.  Still, I am not sure where I would put it if I did take it.  The only place left in my van now to put it would be on the floorboard of the passenger seat.  Stil...I would LOVE to have it!
I am considering that I might need to install a battery monitor in the van to make sure that the agm battery array doesn't overcharge.  And possibly purchasing a multimeter instead.

So, that is where things are.  I hope that everyone is doing well out there!
 
Van on 66 said:
I am considering that I might need to install a battery monitor in the van to make sure that the agm battery array doesn't overcharge.  And possibly purchasing a multimeter instead.

The controller on the Renogy kit has a voltage readout built in.
 
Overcharging should not be a problem on a solar array as the charge algorithm is programmed into the charge controller. Where overcharging could occur easily is an unregulated battery charger you plug into shore power. I have AGM batteries installed inside my van with no venting. They have never off gassed.

A battery monitor is light years ahead of a multimeter for determining state of charge. A multimeter is the least accurate and effective tool for this job unless you disconnect all charging and loads from the batteries for ~12 hours to let them rest so you get an accurate resting voltage.
 
slow2day said:
The controller on the Renogy kit has a voltage readout built in.

Thanks for the reply slow2day.  I was only wondering if I should also have a monitor mounted inside the van so that I could keep a better eye on things.
 
B and C said:
Overcharging should not be a problem on a solar array as the charge algorithm is programmed into the charge controller.  Where overcharging could occur easily is an unregulated battery charger you plug into shore power.  I have AGM batteries installed inside my van with no venting.  They have never off gassed.

A battery monitor is light years ahead of a multimeter for determining state of charge.  A multimeter is the least accurate and effective tool for this job unless you disconnect all charging and loads from the batteries for ~12 hours to let them rest so you get an accurate resting voltage.

Thanks for the info Brian.  I assumed that this would be the case with the charge controller.  I also purchased a Battery Tender Plus so that if I was ever in a place where I had shore power I would only use that to charge the battery.  I guess I am looking into all the possibilities of things that could happen and trying to avoid them as much as possible.  

Can you recommend a battery monitor?
 
^^^^^^ the Battery Tender Plus only outputs 1.25 amps...…that's gonna take a long time to recharge a battery……

In comparison my RV converter/charger is 35 amps and still takes hours to recharge my batteries from shore power
 
You are not going to like my answer...  I am using a Bogart Engineering Trimetric TM-2030-RV battery monitor.  You will also need to add a shunt (I used a 500 amp one) and their cable to connect it all.  I do not use their charge controller.  It also has an input for your engine battery (voltage only).  With this you put in your battery bank capacity and it will give a true readout of what is going in and out and state of charge.  Not cheap but I think the best.
 
B and C said:
You are not going to like my answer...  I am using a Bogart Engineering Trimetric TM-2030-RV battery monitor.  You will also need to add a shunt (I used a 500 amp one) and their cable to connect it all.  I do not use their charge controller.  It also has an input for your engine battery (voltage only).  With this you put in your battery bank capacity and it will give a true readout of what is going in and out and state of charge.  Not cheap but I think the best.

You are right about your answer.  Ouch!!  I get it though.  Unfortunately at this point it is down to getting what I can afford to get me going. So at this point I will just have to deal with getting out of the van to check the status of things from the Renogy Controller readout.
 
Van on 66 said:
You are right about your answer.  Ouch!!  I get it though.  Unfortunately at this point it is down to getting what I can afford to get me going. So at this point I will just have to deal with getting out of the van to check the status of things from the Renogy Controller readout.

FWIW I've been quite happy with Victron's battery monitor for less $$$ than the Trimetric it will do similar things (has a shunt, calculates power in and power out etc), ~$210:
https://www.amazon.com/Victron-Energy-MONITOR-VTBMV-S-BMV-712-Battery/dp/B075RTSTKS
(not that I don't imagine the Trimetric is nice, but the Victron is pretty well thought of too)

Someone above replied regarding your idea of using a battery tender as impractical, I would disagree. They make 5a battery tenders ($80):
https://www.amazon.com/Battery-Tender-022-0186G-DL-WH-12V-Charger/dp/B00EDFPN1O

... and even 10a battery tenders ($110):
http://vi.raptor.ebaydesc.com/ws/eB...tegory=179471&pm=1&ds=0&t=1588425271000&ver=0

These would both be VERY poor choice for charging off a generator as run times would be excessive, but the 10a would probably be pretty reasonable if you were able to plug in with an extension cord overnight every once in a while. Plus at 120w (10a @ 12v) you'll have no problem using a relatively inexpensive extension cord on a 15a household outlet, no 30a RV style cord required.

Our sailboat has 3x75ah deep cycle batteries plus a start battery and it's charger is only 10a... so again, not good if you're trying to charge your batteries in a few hours (although that never works anyway as the last 10% of the charge takes so long) but even if I'm drawn down to 50% by the time I get to shore power if I'm plugged in 12 hours overnight that's ~120ah back in (minus some inefficiencies).

-- Bass
 
nature lover said:
Don't take this for gospel - I am not a tech guy. I have charged my laptop battery with one of those cheap cig plug inverters. I think I was told that I could charge it that way when the unit is off but not while it is up and running. One of you folks that knows about these things please let me know if that is right.

You can use modified sine wave over pure sine wave for charging laptops. Can vs should is the real question. The issue is the active protection circuits in modern laptop power supplies. They are designed to protect the power supply from occasional voltage spikes. The voltage spikes from modified sine are pretty frequent and can eventually kill that circuit, then you will get decreased (possibly inconsistent) charging. The likelihood of damaging the laptop is pretty low, the AC adapter relatively moderate. Depends on how often you plan on using this setup. Once a week, probably will replace the laptop before the adapter. Daily, I'd have a backup adapter on hand. They are cheap, and for the price difference between the two inverter types, you could go a couple of years of having a backup brick before hitting the cost of a more expensive inverter. I've been in IT since 1992, spent 6 years from 2000-2006 repairing laptops, now Sr Sys Admin for a SaaS. I use a modified sine wave.
 
I havent had any experience with this "solar generator" type battery. It's not a generator, it's a battery.

https://www.amazon.com/Rockpals-Portable-Generator-Flashlight-Emergency/dp/B07FFNTGZ6

I liked that it was 280 watt hours of lithium with a 300 watt 600w surge pure sine wave inverter that can be charged by solar, wall, or ciggy charger. But beware if ran until dead it can only be reactivated by wall charger.

Super portable and has 12v barrel connectors as well that can run 12v lights very plug and play type with these.

https://www.amazon.com/Renogy-5-5mm-Light-Bulb-Socket/dp/B07BND64YS

https://www.amazon.com/gp/aw/d/B07MFYB54S

The bulb I linked when I ran off of a usb buck converter read 7 watts not 5 watts. Probably conversation losses.

Also has QC (quick charge) USB 3.0 plugs. Pretty portable compact unit. Not cheap. Not a lot of stored power. About as portable and feature packed as you could possibly ask for though.
 
I also thought about getting one or 2 of these with that battery pack. They output 15 watts of 14.6v DC power by throwing them into a river and can be daisy chained together. 2 of them would provide 30 watts. Not a lot of power but they run when the sun is down. At max theoretical output you'd generate 720 watt hours per day (30w * 24h = 720wh). Not too shabby if you boondock beside a creek. I even saw a video of a sailboat towing one and it was generating more like 17 watts if I recall. Maybe more.

https://www.amazon.com/WaterLily-12V-Portable-Boaters-Campers/dp/B07MWHJZSW
 
Thanks for all the input. I have been officially off the grid now for a week using a Renogy Eclipse 100 watt folding panel solar suitcase. Since all I am running is a laptop and charging small batteries it is working great and I am really happy with it. Still, I realize that there will be days when there is no sunshine and I will need some kind of a battery bank,etc. and I am already looking into what to do for those days.

At this point I am looking into the Maxoak 50,000 mah power bank. It has some great reviews and you can still pick these up for around $100.00.
 
I havent looked up that powerbank but those are often rated in the 5 volt range as far as I know. So 50k mah is better than the pair of 20k mah that I have. Especially as 1 of mine died on me. But 100k mah 5 volt isnt the same as a 100k mah 12v I'll tell ya. But with a USB buck converter I can run a 7 watt 12 volt light bulb for about 10 hours on a marked 74wh battery bank. 10h * 7w =70 usable watt hours from a marked 74wh battery. Conversion losses I'm sure.

But as a laptop charger sure its possible. Hell anything is possible. But the buck converter peaks out at 10 watts or so. So youd need to daisy chain multiples with blocking diodes to run say a TV. Anything that gets that complicated is deserving of an upgrade.

So its ingenuity vs reliable portability vs stationary reliability. They all have their advantages. The homemade lithium option makes me cringe but its possible. The stationary van mount seems the most advantageous unless you make camp away from the vehicle. Pick your poison.

My 2 cents.
 

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