Simple solar battery charging for an anit-solar kinda guy?

cruiseroutfit

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OK, I guess I'm not anti-solar. More appropriately it's just never been something I've needed. I've always had a dual battery system, fairly low power supply needs when not running (fridge, minor lights at night, phone/gps charger, etc). I think the biggest factor is I don't often stop and camp out for more than 3-4 days at a time rather we are usually driving on a daily basis so the dual battery system does all the heavy lifting.

But, I'm ready or at least I think I am. I'm running into a couple of issues the main one is the vehicles just sitting, sometimes for weeks or months at a time. Nothing is running, fridge is unplugged, etc Radio's have memory, battery's have losses, etc. I've been pretty good about keeping them on trickle chargers and the Nat Luna system will charge both batteries with a single charger so it isn't a huge deal. Issue #2 is camping for more than a few days and not wanting to run the vehicle for extended periods just to get a somewhat superficial charge. So, I've started looking at a panel that would accommodate my wants/needs all while being fairly robust and easily transportable, i.e. not fixed to a roof-rack. I've read through many of the links in the FAQ and there was some great general info but much of is it quite dated and solar panel technology seems to be improving pretty fast no?

So, I'm really looking for a recommendation for a solar panel and charge controller (the two integrated would be killer) that can have a pair of alligator clips on the end an offer a decent output (50+ Watts too much to ask). I'm seeing some random options on Amazon that look like the might fit the bill?

Hard panel 120W, decent reviews albeit weak legs which I can upgrade easy enough. Not sure it will be easy to transport long-term without damage?
https://www.amazon.com/gp/product/B00MGLIIQO/ref=ox_sc_act_title_1?ie=UTF8&psc=1&smid=A5KU5HDAPDC75

Add these clips and I'm golden:
https://www.amazon.com/gp/product/B00MEQVJQW/ref=ox_sc_act_title_2?ie=UTF8&psc=1&smid=AU5MW0P13QZ5V

I really prefer a fold-able soft panel such as these:
https://www.amazon.com/gp/product/B00EVFEBKU/ref=ox_sc_act_title_4?ie=UTF8&psc=1&smid=AU5MW0P13QZ5V

But they have really mediocre output. Totally opposite ends of the spectrum (27W vs 120W) but I think I should emphasize I'm open to any recommendations for what has worked for you? Any suggestions or links I can look at?
 

broken1

Observer
So the http://www.amazon.com/ECO-WORTHY-120watts-Polycrystalline-Photovoltaic-Portable/dp/B00MGLIIQO/ apparently comes with everything you need for original concept of operations. It has an integrated charge controller and alligator clips see the other pictures on Amazon. Set it up, clip it to the main battery and it and the national luna should do the rest.
Skip the http://www.amazon.com/Instapark-INCC1205-Waterproof-Charge-Controller/dp/B00MEQVJQW/ as it isn't rated high enough for those panels and you don't need it for the above reasons.
Soft panel sets might be good for backpacking or something but vehicle mounted/used I wouldn't bother the price is too high for what you get in terms of performance.

That Eco-Worthy portable set is actually a pretty slick piece of kit. The legs being "weak" is something that could be easily overcome with a trip to the local hardware store. I wouldn't shy away from it for only that reason.

If you wanted another option:

I think I would want two different solutions. For at home parked, a little panel on the dash (assuming vehicle is outside) like this: http://www.amazon.com/ALLPOWERS-Maintainer-Automobile-Motorcycle-Batteries/dp/B00QRHDIPY/ plugged into a constant hot cigarette lighter or on a quick disconnect tied into constant hot will take care of your resting discharge just fine. 5 watts is a little less than half an amp so no worries about over charging or anything and should be able to offset the parasitic losses just fine.

For keeping it filled on the trail during usage I think a different solution fits your needs. I know you have the national luna but it takes current to hold that solenoid in place. This is an unnecessary power consumption in my opinion. When you have a 140A alternator spinning, it isn't a concern but when you are talking about solar the less you waste the better. I would disable it when not driving.

DISCLAIMER: I am definitely a fanboy of Morningstar charge controllers. I am biased, but so is everyone else...

I really like the Morningstar Sunsaver Duo. I have it and have no complaints. It is a solid 25A 12V charge controller (room for expansion for your application should you choose) that splits the current flow 90/10, 50/50 or with programing to some other ratio. You hook one side to the vehicle battery, one side to the house/fridge battery and let it do it's thing. I like 90 to the chassis battery and 10 to the house. As soon as the chassis is topped off it goes 100% to the house ensuring that you can always start up and drive away. If the chassis should drop off again it will proportion back. http://www.amazon.com/Morningstar-SSD-25-SunSaver-Charge-Controller/dp/B007NNMEU6/ I've used it with alligator clips with no issues (for battery rotation) I bought super cheap 10ga jumper cables cut one set of ends off and put them in. Like these: http://www.amazon.com/ALEKO®-CH-NA002-Booster-Jumping-Battery/dp/B00P9JFIEU/

If you are looking to go less costly on the charge controller, these are a knock off with a similar concept of operations:
http://www.amazon.com/SainSonic-Battery-Charge-Controller-Regulator/dp/B008HWSA78/ 20a
http://www.amazon.com/Battery-Charge-Controller-Regulator-battery/dp/B008KWPFGO/ 10a
But I can't vouch for them.

As far as panels go that set you referenced is nice, and if you think it will fit your needs (i.e. not fixed to a roof-rack) it seems like a winner. Heck my current mobile set is two of the HF sets because I got given one and the other was dirt cheap. Had I to do it all over again I wouldn't bother. The bang for buck is low. The renology 100 watt panels http://www.amazon.com/Renogy-Watts-Volts-Monocrystalline-Solar/dp/B009Z6CW7O/ cost about the same and are more than twice the power. The HF charge controller is garbage and so are the mounts (although the newer PVC based mounts are a little better than the older metal. I have both.) I would do the Morningstar controller and make my own easy takedown mount angle iron and unistrut or something easily fabbed from hardware store fare.

For transportation, like big screen TVs, traveling on edge in a well padded arrangement is best, but impractical in many situations. I store mine horizontal with the whole glass supported by a sheet of closed cell foam (like the .75 inch tool box lining stuff) It separates the panels and insures that the load is distributed, limits bounce loading from movement etc. I'd do a piece in the middle of the panels and a piece on each outside and it should be fine maybe notch out for that charge controller in the middle piece.

tl;dr
1@ http://www.amazon.com/ECO-WORTHY-120watts-Polycrystalline-Photovoltaic-Portable/dp/B00MGLIIQO/
= good to go

1@ http://www.amazon.com/Morningstar-SSD-25-SunSaver-Charge-Controller/dp/B007NNMEU6
+ 2@ http://www.amazon.com/Renogy-Watts-Volts-Monocrystalline-Solar/dp/B009Z6CW7O/
+ 2@ http://www.amazon.com/ALEKO®-CH-NA002-Booster-Jumping-Battery/dp/B00P9JFIEU/
+ a home brew mount
= better (in my opinion)
 

AndrewP

Explorer

cruiseroutfit

Supporting Sponsor: Cruiser Outfitters
Thanks for the great info guys!

I ended up going two routes, one for charging @ camp. One for trickle when parked.

Andrew, I opted for the Renogy 100W and a Renology 30Amp Charge Controller, thanks for the Renogy recommendation.

I'll update when stuff shows up and I get a chance to use it.
 
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cruiseroutfit

Supporting Sponsor: Cruiser Outfitters
Alright, we may be onto something here. Truck sat for 3 days in the sun, other than moving it a couple of short trips (under 5 mins of run time) the solar held the batteries in the "green" if you will (using the National Luna gauge, voltage only). While this isn't remotely surprising for the Red Top main/start battery, this was nice to see out of my aux Yellow Top considering we had the fridge at 35* and phones & laptops charging. I occasionally tested amperage out of the panel, with mixed cloud conditions I was seeing .5-3.25 amps. I've got an inline power analyzer on order that I will integrate into the system so I can more monitor the system a bit better during future use. Thanks again for the Renogy recommendation.

If I had it to do over again, I think I would give this a try:
http://www.amazon.com/Renogy-Portab...441671895&sr=8-1&keywords=Renogy+100w+folding

This as my only complaint is the size of the 100W panel that fits inside the rig but not really conveniently. I built some folding legs that make it easy to setup and store back in the original box but that isn't going to be a long-term solution.

Testing wiring the system pre-desert:
solar (Small).jpg
(Optima yellow top was the load battery, I had an Engel MR040 plugged in and in full sun I was only pulling 1/2 amp off the battery when the fridge was running. When the fridge was not cycling, it was dumping ~1-2A back into the battery.
 
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DiploStrat

Expedition Leader
One Observation

Remember that many battery manufacturers want a minimum charger capacity. If memory serves, Lifeline wants 20A of charge for every 100Ah of capacity.

A 100w panel will typically give you 5-6A of charge in good light. There is a kind of magic that occurs when you get up into the 15A+ range. Things go a lot better and faster.

The real mojo of solar is, however, the ability to provide that long absorb stage that lead acid batteries need so badly. Alternators (with appropriate wiring) can give you bulk, but you often need solar (or shore) to complete absorb.

Glad things are working out.
 

cruiseroutfit

Supporting Sponsor: Cruiser Outfitters
Interesting point DiploStrat, I'll have to give that a look and make sure I'm feeding enough current to the batteries. I'm not sure what Optima wants as for a charger capacity but I have several different 120V chargers with Optima (AGM) modes. Ctek 7002US & Genius G3500 and just picked up the G7200 as it does 24V diesel stuff. The Ctek has a 7A max, the Genius G7200 has a 7.2A max on 12V, the 3500 a 3.5A max, though I'm not sure they use that max for the AGM versus it's different charge modes. I'll have to dig into it a bit.

I did find this:

Yellow-Top Recommended charging information:

Alternator:
13.65 to 15.0 volts, no amperage limit.
Battery Charger:
13.8 to 15.0 volts, 10 amps maximum, approximately for 6-12 hours.
Cyclic Applications:
14.7 volts, no current limit as long as battery temperature remains below 125°F (51.7°C). When current falls below 1 amp, finish with 2 amp constant current for 1 hour.

Rapid Recharge:
Maximum voltage 15.6 volts (regulated), no current limit as long as battery temperature remains below 125°F (51.7°C). Charge until current drops below 1 amp.

Float Charge:
13.2 to 13.8 volts, 1 amp maximum current, time indefinite (at lower voltage)
.

http://www.optimabatteries.com/en-us/support/battery-care/charging/

Looks like I'm OK on both the cyclic uses and the float charge situation.

Red-Top Recommended charging information:

Alternator:
13.3 to 15.0 volts, no amperage limit.
Battery Charger:
13.8 to 15.0 volts, 10 amps maximum, approximately for 6-12 hours.
Rapid Recharge:
Maximum voltage 15.6 volts (regulated), no current limit as long as battery temperature remains below 125°F (51.7°C). Charge until current drops below 1 amp.
Float Charge:
13.2 to 13.8 volts, 1 amp maximum current, time indefinite (at lower voltage).


Looks like I'm OK there too.
 

cruiseroutfit

Supporting Sponsor: Cruiser Outfitters
Forgot to mention. The input voltage was enough (requires 13.2V) to trigger the National Luna's Intelligent Solenoid, thus charging both batteries at the same time. Not sure if this plays in my favor with low input current given the previous post but both batteries stayed really topped off. Here is the catch, the Intelligent Solenoid demands up to 780mA when the solenoid is engaged. That is some pretty massive power when we are talking 10-30% of my solar panels current output. I knew this going in and had only planned to use the panel on the Yellow-top (which is powering all the aux gear in the rig) as it won't fire the solenoid in that direction. More tinkering required :D
 

DiploStrat

Expedition Leader
Kurt, those all look typical of modern FLA or AGM lead acid batteries. (There was a time when AGM batteries tended to run a bit lower than FLA.) I would guess that the low amperage given as "battery charger" is assuming a dumb, fixed voltage/fixed amperage, single stage charger, and so they specify a lower charge and long time.

Most solar chargers and inverter/chargers (like the Magnum in my truck) are intelligent chargers in that they attempt to go through a multi stage charge; bulk>absorb>float. In this case, you ramp up the voltage and amperage in bulk, drop the amperage in absorb and, finally, drop the voltage in float.

N.B. Many vehicle alternators are now multi-stage. I was intrigued to learn that many Toyotas have relatively low charging voltages, only 13.9v in the case of an FJ. You may wish to look into this as, if it is true, it will slow down your charge when charging from the alternator. There are devices to raise the voltage on Toyotas or you can explore the world of Battery to Battery chargers from CTEK or Sterling. See long pedantic arguments here: http://www.expeditionportal.com/forum/threads/147340-Dual-Battery-Shore-Power-Charging-Question
 

AndrewP

Explorer
As a side point here, if the 780mA figure is correct, you need a different "intelligent" solenoid. That's close to 15% of your panel's output just to power the solenoid. In contrast the Blue Sea 7610 which performs a similar function uses 175mA.

Or, you could disable the NL voltage sensing relay electronics, so it does not combine, and just count on your starting battery to be OK just because you are not using it.
 

cruiseroutfit

Supporting Sponsor: Cruiser Outfitters
As a side point here, if the 780mA figure is correct, you need a different "intelligent" solenoid. That's close to 15% of your panel's output just to power the solenoid. In contrast the Blue Sea 7610 which performs a similar function uses 175mA.

That is their published number, I can certainly test to see how accurate it is. That does seem high?
http://www.nationalluna.com/intelsol.htm

Or, you could disable the NL voltage sensing relay electronics, so it does not combine, and just count on your starting battery to be OK just because you are not using it.

It actually works this way on it's own, it only combines when it sees voltage on the main battery side, not the aux side so I as I have minor or no drains on the main and I plan to charge only the yellow, it should work out.
 

Chris Boyd

Explorer
I'm running into a similar issue. I have the solar going to the aux yellow top ,but I have some parasitic draw on the starting battery that I just can get rid of... I've moved everything I can find to the aux side. I was thinking when I am home, run the solar to a plug on the main battery, thus allowing the luna to join - thus both batteries get charged. In the field, I think I can go about 5 days on the starting battery with the parasitic load, so I really only need to charge the aux side.

So for now, I just connect to a different plug when in the field vs. "storage mode" where I have PVs just keeping the batteries topped up for the next run.
 

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