Solar panel to maintain 95Ah battery

[4x4Maniac]

I'm considering this as an option in order to maintain the battery during the day when parked etc at work or camping somewhere for a day or two.

The main idea is to not let the aux battery go below 50% of its capacity. When driving I have the NL dual battery system and alternator charging the battery. I also have the Waeco 50L running permanently on 0C. On a really hot day it discharges the battery to about 50% over a 9h period.

http://www.bushpower.co.za/products.asp?pid=558" onclick="window.open(this.href);return false;

Do you think this wil work when mounted flat on the bakkies roof, knowing it won't be optimum.

I also saw ODW selling a 20W for R800 or should I not waist any money and get this 90W kit with frame and everything?

http://www.bushpower.co.za/products.asp?pid=289" onclick="window.open(this.href);return false;

Remember I don't have a roofrack yet.

[Niel]

I have this intended setup running now for 2 years and to date it works for me.
Things to remember or rather what I do: (I run either a 102 and or a 105 A deep cycle and sometimes both as I have 90 NL in the setup sometimes)
- I switch the fridge off when I go to sleep (i.e. this weekend it was at 0 deg when going to sleep and when it was switched on the next morning it was at 4 deg)
- the solar panel is removed from the roof rack when camping for longer than 2 days - to use the panel output optimally
- setup/connect the panel first thing in the morning

pls shop around here in CT as there are a few suppliers(Tenesol, Setsolar, Solair direct and GW Stores CT) that can sell you the components and you might save a few rands. Phocus are an imported brand and are very good. The Steca is the "better" controller according to most but it comes at a price. I use the TES 15 A (around R 175) and a Ener10 (was around R 300, 3 years ago). I will see what pics I have of the setup.
You are more than welcome to come and have a look at the setup as well.

Sorry, forgot to mention I run the bakkie setup off a 90w Tenesol monocrystal panel) and the trailer off a 80 w Canadian solar panel.

I hope this helps?

[4x4Maniac]

Thanks for the input Niel, but unless I go on holiday I won't be able to pop in for a visit! I'm in Centurion.

I also like the idea of having it mounted, but removing it when camping for 2 or more days.

[Niel]

but unless I go on holiday I won't be able to pop in for a visit! I'm in Centurion.

- sorry did not check the location
always and option .

[mushroom]

Hi Werner,

Give these okes a ring in Kya Sands - they have really good prices on their kits..

http://www.rectifier.co.za/" onclick="window.open(this.href);return false;

I got my setup from them (80W panel, 20m cable, panel bag and suppourts) for R 3000.00 odd - well worth it. In Nxai pans I was able to run the 50lt Waeco at 0deg during the day with the car off. Not only did the panel keep the fridge running, but it also actually charged the battery up !! it definitely helps if you move the panel thru the day to keep it at the optimum angle to the sun - then they work like a bomb !!
good luck - cheers

[george]

Hi Werner.
I have the 85 watt and it works relatively well.In hind site I would have gone for a bigger one.Even with my 85watt you have to "chase" the sun.

[Niel]

You have top move it regularly but I do it when I fetch a cold beer

[mushroom]

You have top move it regularly but I do it when I fetch a cold beer

Likewise and as the sun sets youre well on your way....
Just dont drop the panel...

[Niel]

James - very true

[Niel]

I will see what pics I have of the setup.

Panel on the roof and a sleeved wire from the panel connector to the regulator that is velcro-ed to the NL battery box.

[Johan Kriel]

I use only one 80Ah AGM battery in the vehicle, but use 3x50Watt panels hinged together (measuring about 800 x 500 x 150mm when folded in a custom made bag) on the days that we are not traveling, running an 80l engel fridge on -4 C continues (setting 2), and we open and load the fridge as we like, even now when was travelling through the Koakoveld.

I would say rather spend money on larger panels, they are cheap now anyway.

[george]

I use only one 80Ah AGM battery in the vehicle, but use 3x50Watt panels hinged together (measuring about 800 x 500 x 150mm when folded in a custom made bag) on the days that we are not traveling, running an 80l engel fridge on -4 C continues (setting 2), and we open and load the fridge as we like, even now when was travelling through the Koakoveld.

I would say rather spend money on larger panels, they are cheap now anyway.

Johan I agree with you.140watt would have been 100% for my needs

[JJBotes]

Sub

[chopper]

I'm trying to arrive at a best-value-for-money option for a semi-permanent installation/deployment to operate/sustain a 40 and/or 74l fridge(s) as well as charge a deep-cycle battery for camp lighting (all LED). Panels are bought at a R/watt rate - would it make sense then to rather buy a large (as possible) panel vs 2 medium-sized panels, either set-up functioning with a single regulator

[Donkey]

Hi Werner, from experience this holiday in Namibia and Botswana, we experienced temperatures around 38 degrees, I don't have the split charger or solar panel but just a 12A DC/DC charger, charging a 105 Ah Deltec battery, which was sufficient to keep the fridge running for about two days, which worked well for camping sites without power.

I have never had a split charger set-up but from what I can gather is that it does not charge the deep cycle battery adequately so it operates at optimum capacity. Just my 2cw

That said I would consider a solar panel for places without electricity if staying more than 2 days, a project for later this year towards holidays again.

[4x4Maniac]

Yip I mos saw that DC2DC Charger and perhaps in hindsight should have rather opted for that option, however, now I think the best option is to have a 80w solar panel that maintains the battery and then also have a bit extra for the inverter.

[mushroom]

DONKEEEEYYYY - hows that trip report coming along !!!

[JJBotes]

DONKEEEEYYYY - hows that trip report coming along !!!

+1

[Donkey]

Trip report is done, we were writing it day by day, Sebata has it on his tablet, said he'll upload when he gets to work, currently down with flu, I will then follow up with the pics. But all in all a lovely trip, just the two of us in my KZ. Did about 5000 km and 3 countries - ie. Namibia, Botswana and Angola (on a boat our neighbours had)

[4x4Maniac]

Nice, I'm really looking forward to the report! Did lunchbox join you?

[Tonto]

I am at the last stage of my December trip. At the moment relaxing in Pearly Beach. I have learned a lot about charghing batteries during this trip, mostly that it seems the alternator is not good enough [standard Bosch] I tried to read various forums about dc to dc chargers, but there seems to be a lot of opinions. One guy evens discounts the dc to dc cargers as nonsense. It seems the thicker the charging cables the better. Otherwise a dc to dc charger and/or solar panel. I would like to hear any other experiences.
Most importantly, check your terminal connectors on the alternator, on Rooi Oog the were corroded and the alternator was serviced, voltage regulator replaced lots of time and effort spend and no-one considered the most obvious reason for charging problems.
May all of you have an excellent 2013.
Regards.
Andre.

[Johan Kriel]

Deep cycle batteries (AGM and those type) like a higher charging voltage but lower amps than start batteries. Thus you can charge a start battery quicker from the alternator, but an alternator would not be as efficient on a deep cycle than a dc to dc charger. The charge cables should thus be sized accordingly. The question thus which setup is the best; Deep cycle plus DC to DC charger or solenoid and start battery.

I think with a smaller fridge the solenoid setup with a start battery is sufficient and you can maybe skip driving one day, but with a larger fridge (higher demand) a deep cycle setup might be worth while.

[4x4Maniac]

Most importantly, check your terminal connectors on the alternator, on Rooi Oog the were corroded and the alternator was serviced, voltage regulator replaced lots of time and effort spend and no-one considered the most obvious reason for charging problems.

Thanks Andre,I'll keep that in mind.

Does anyone know what the output Voltage/Amps should be directly over Alternator, main battery and aux battery when started and running?

[Aquanaut]

Does anyone know what the output Voltage/Amps should be directly over Alternator, main battery and aux battery when started and running?[/quote]

Hi, check out the National Luna web site on Google and you can down load their operating manuals which will give you all the info needed.
Basil

[Willem01]

Hi Werner

Just to give you an idea ....I have 2 x 50W panels on the roof and a deep cycle 95Ah battery...... currently connected to it is a 60l Campmaster fridge and a set of 5 x 1 watt (3 LED light modules) for light under the gazebo.

Was camping for 5 day's at Umoya....we used the fridge as we wanted as it was left in the bakkie on the fridge slider it was running constantly at -2 Celsius set at 5 during the day and at night it went down to -12 C ,,,, the whole time I checked the voltage rating on the battery and found that it never dropped below 12.86v, even with 2 days been bewolk , I am very happy with my setup.

[Tonto]

Hi Werner

Just to give you an idea ....I have 2 x 50W panels on the roof and a deep cycle 95Ah battery...... currently connected to it is a 60l Campmaster fridge and a set of 5 x 1 watt (3 LED light modules) for light under the gazebo.

Was camping for 5 day's at Umoya....we used the fridge as we wanted as it was left in the bakkie on the fridge slider it was running constantly at -2 Celsius set at 5 during the day and at night it went down to -12 C ,,,, the whole time I checked the voltage rating on the battery and found that it never dropped below 12.86v, even with 2 days been bewolk , I am very happy with my setup.

Willem, how is this connected to your electrical system?

Regards
Andre

[4x4Maniac]

Thx Willem. That helps a lot. I'm really keen on the solar setup and think to go at least 80w. Just gonna start saving for this setup.

[Aquanaut]

How much would 2 x 50w panels cost?

[Johan Kriel]

Panels are now about R15/watt

These portable Fridges use about 1.3 to 2 Amps (40l to 80l fridges) average per hour in hot conditions, obvious less in cooler temperatures. Thus you need to replace that Amp hours which could be 36 to 48hours running time, if not driving one day, more if standing longer,which could be be 40 Ah (1.3x30) to 96Ah (2x48) depending. For 40Ah you would not need a solar as the battery alone can provide, but for 96Ah one battery is not sufficient and you need to replace at least say 50% (allow some safety factors) to keep the fridge running, which is 48Ah (50% of 96Ah)and with 6 hours charging time on solar you need to put back 48/6= 8 amps which is about 130 Watt (8Ax17v) panel.

Thus one need to make some calculations on your need and plan form there. A 80 watt panel could be sufficient for a small fridge providing even for a couple of days, but for a bigger fridge you may coupe only one day.

I would say rather start with smaller type, like a 50watt, and add one or two if you need more cells, and hinged them together. From 80 watt cells and larger get very bulky to carry around.

[4x4Maniac]

Thanks Johan, that makes sense.

I've asked a contact of mine to provide me with both dimensions and price of 2x 40/50w vs 1x 80/100w panels, because the bigger the panel the less you can load on the roofrack.

[Aquanaut]

Thanks Johan

[Willem01]

[/quote]

Willem, how is this connected to your electrical system?

Regards
Andre[/quote]

The system is a standalone setup the deep cycle battery is not connected to any electrial from the vehicle .

Panels are now about R15/watt

These portable Fridges use about 1.3 to 2 Amps (40l to 80l fridges) average per hour in hot conditions, obvious less in cooler temperatures. Thus you need to replace that Amp hours which could be 36 to 48hours running time, if not driving one day, more if standing longer,which could be be 40 Ah (1.3x30) to 96Ah (2x48) depending. For 40Ah you would not need a solar as the battery alone can provide, but for 96Ah one battery is not sufficient and you need to replace at least say 50% (allow some safety factors) to keep the fridge running, which is 48Ah (50% of 96Ah)and with 6 hours charging time on solar you need to put back 48/6= 8 amps which is about 130 Watt (8Ax17v) panel.

Thus one need to make some calculations on your need and plan form there. A 80 watt panel could be sufficient for a small fridge providing even for a couple of days, but for a bigger fridge you may coupe only one day.

I would say rather start with smaller type, like a 50watt, and add one or two if you need more cells, and hinged them together. From 80 watt cells and larger get very bulky to carry around.

Very nice said Johan I might also learn something from this

[Aquanaut]

Any place here in Durban that is recommend to supply such panels??

[Wayne]

My national luna dual battery system was stolen out the back of my bakkie about 2 months back so I had the chance to rethink how I was going to supply power to my fridge etc.
I got a 130W solar panel and a 10W controller.
We camped for 6 days in one spot with temperatures getting up to 41 degrees.
The battery never went below 11.5v overnight and within an hour or two of the sun rising it was at 13.5v.
This was a stand alone system, there was no connection to the vehicle charging system.
I will never go back solely to a system that relies on the vehicles alternator for charging.

The 130 W panel cost R1500 ( R12 per Watt) and the 10W controller cost R500.
Both made in Germany with a 10 yr warranty.

Contact MLT Drives http://www.mltdrives.com" onclick="window.open(this.href);return false;

[Niel]

I see from the spec sheet that it is a Tensol panel - have a 90w from them. Did not know that they changed their name.