Author Topic: Solar panel to trickle charge a 12v battery?  (Read 7606 times)

Offline raynerd

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Solar panel to trickle charge a 12v battery?
« on: December 10, 2013, 05:04:07 PM »
Evening guys,
Just wondering if any of you have done this and can give me any advice or info.

My plan is to use a 40w solar panel which I can purchase for £50, connect this to a regulator so that the battery doesn't get overcharged £20, then to a car battery or a leisure battery.

I've just got an allotment and I can't cope without any power! Even if it is just a small radio and small LED light for the shed/lean-to.

I have a few questions and pretty sure someone can offer advice -

1. Does the solar panel wattage effect the power generated on cloudy days or is it just a case of the maximum power output on a sunny day?? My point is, if it is a crappy winter day with little sun, will a higher wattage panel going to generate more power?

2. What sort of lighting will be available to me on 12v battery supply and with something "decent" how long will it allow me to be lit for?


Basically, during winter I go to work in the dark and come home in dark. A light would allow me to at least go up for a while. I'm curious how long a light would run and in the winter - if a solar panel could fully charge the battery or will only top up a low battery. If it will fully charge - on a winter day (white clouds) how long would this take?

Hope someone can lend some info and advice.

Chris

Offline angus

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Re: Solar panel to trickle charge a 12v battery?
« Reply #1 on: December 10, 2013, 05:09:05 PM »
i run an extractor fan in my workshop, off of a 20w panel... its a 12volt fan, and it always amazes me how hard it runs on a cloudy day

if you run led lighting, you will be fine....

i would suggest something like
http://www.ebay.co.uk/itm/350871703543?var=620161368040&ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649

it will look a bit santa's grotto, but the wont deteriorate in the damp of a shed

Offline awemawson

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Re: Solar panel to trickle charge a 12v battery?
« Reply #2 on: December 10, 2013, 05:33:51 PM »
I have a 'road compressor' - big diesel engine - that I use infrequently for sand blasting. The battery always seemed to be flat when I wanted it. Last Christmas my eldest sun gave me a solar panel measuring about 5" x 12" which was supposed to keep a vehicle's battery topped up. I was skeptical but put it on the compressor anyway.

Since then I've had no problems with a flat battery !

Andrew
Andrew Mawson
East Sussex

Offline John Stevenson

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Re: Solar panel to trickle charge a 12v battery?
« Reply #3 on: December 10, 2013, 06:43:20 PM »
Last Christmas my eldest sun gave me a solar panel

Andrew

Was that perpetual motion ?   :Doh:
John Stevenson

Offline awemawson

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Re: Solar panel to trickle charge a 12v battery?
« Reply #4 on: December 11, 2013, 03:19:39 AM »
You were the only one to spot that pun about the sun, John  :ddb:

Andrew

ps bally cold here this morning, minus five Centigrade and the pig poo is frozen to the concrete in the sty  :bugeye:
Andrew Mawson
East Sussex

Offline Fergus OMore

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Re: Solar panel to trickle charge a 12v battery?
« Reply #5 on: December 11, 2013, 05:01:54 AM »
Is the  perpetual motion  frozen for the time being?


Norman


Offline awemawson

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Re: Solar panel to trickle charge a 12v battery?
« Reply #6 on: December 11, 2013, 06:20:37 AM »
Bright sun so it should still be charging, Norman  :lol:

Andrew
Andrew Mawson
East Sussex

Offline Fergus OMore

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Re: Solar panel to trickle charge a 12v battery?
« Reply #7 on: December 11, 2013, 07:38:10 AM »
Back to a bent boaring tool, methinks?

Oops

N

Offline chipenter

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Re: Solar panel to trickle charge a 12v battery?
« Reply #8 on: December 11, 2013, 04:23:41 PM »
My lathe is powered by two car batteries and use two small 1.5 what solar panels from Maplins , I only have to chage them if I am using the lathe a lot for three of four days ,
Jeff

Offline Dawai

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Re: Solar panel to trickle charge a 12v battery?
« Reply #9 on: December 12, 2013, 09:54:42 PM »
we installed a 10 amp 120 watt solar panel ($150??), a single deep discharge rv style battery ($65) in the basement here. Bought a charge regulator that is also "programmable" for less than $20..

I have several 48 LED arrays around the house, gave like $12 for five of them. We have power to see, even if a tornado rips the upper portion off and we are crouching in the basement. THE light is so bright it hurts to look at it like a welder. I have been turning them to the wall and letting it reflect and light the room.

A simple starter kit.. and yes, over five very rainy cloudy days all those LED's running program to stay on from dark till sunup did lower the battery to each night it shut off at about 3am low voltage cut off at 12.5 volts..

We are satisfied so far.. if you want I can get part numbers for all of it.  I want to build some custom floor lamps.  Perhaps you all can help me design some cheap ones using fruit jars as shades.
I Hung a 24 foot Ibeam this morning in the ceiling by myself, programmed a Arduino this afternoon for a solar project, Helped a buddy out with a electrical motor connection issue on the phone, then cut up a chicken for Hotwings. I'd say it has been a "blessed day" for myself and all those around me.

Offline velocette

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Re: Solar panel to trickle charge a 12v battery?
« Reply #10 on: December 13, 2013, 02:20:21 AM »
Hi
This works well on our sliding gate charging a battery that opens and closes it has been in use the last seven years.
Built the sliding gate and removed the two meet in the middle hinged gates.
All came about when the good lady of the house did a pantomime act in a rain squall opening one gate and going to open the other gate and the fist gate swung back closed. Several rounds of this dance and soaking wet by now and no further forward. "You fix the "B***** gate and installed herself back in the car.

Eric

Offline Fergus OMore

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Re: Solar panel to trickle charge a 12v battery?
« Reply #11 on: December 13, 2013, 02:52:02 AM »
I think that we Brits are not quite with this solar panel thing.  Maplins has been flogging solar battery chargers for umpteen years. At the price, it is difficult to build one up to compete. I have a car in Spain and  it is used for perhaps 2 months annually and my son suggested taking one out. to top up the battery. My Mercedes SLK230 rarely does 70 miles a year and I've considered the same here. However, we live in a tree zone where all the trees are listed and cannot be removed without permission. So it is trickle chargers from the mains supply.

The Brits are literally playing with solar power, the Germans have every farm in Bavaria roofed with panels and this has been so for more than a couple of decades. Somewhat bitterly, we haven't a clue about weather. Winter comes as a surprise every year. We've had a storm almost as ferocious as in the Phillipines and there is another one- sitting out ready to come in.


Offline Noitoen

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Re: Solar panel to trickle charge a 12v battery?
« Reply #12 on: December 13, 2013, 04:28:28 AM »
I have a automatic gate opener on a remote location with a 35V no load output panel always connected to a pair of 12v gel batteries for 4 years now, using this regulator http://www.ti.com/lit/ds/symlink/lm2576.pdf The current is limited to 3A and the output voltage is set to 27V.

Offline Pete49

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Re: Solar panel to trickle charge a 12v battery?
« Reply #13 on: December 13, 2013, 09:57:06 PM »
just another comment from a user of solar. I have a 25 acre bush block that we spend time on except for  summer (too hot) and our shed is solar powered for lights and some electronics (laptop/ph chargers and tv) and all we use is old car batteries for storage as we find that even though they can't crank over the car they hold enough charge to do what we want. Maybe visit a trucking company and see if you can get 1 or 2 older batteries from them as they tend to be bigger than a normal car battery. Because of the lower amount of sun hours where you are maybe go for an 80watt panel. Let us know what you end up doing.
Pete
oops..........oh no.........blast now I need to redo it

Offline Dawai

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Re: Solar panel to trickle charge a 12v battery?
« Reply #14 on: December 14, 2013, 03:24:33 PM »
http://www.amazon.com/gp/product/B009Z6CW7O/ref=oh_details_o05_s01_i00?ie=UTF8&psc=1 panel was $150 something when we bought.. I think.. NOW $160

http://www.ebay.com/itm/5x-12V-Car-48-SMD-White-LED-Light-Panel-T10-Festoon-Ba9s-Dome-USA-Ship-/300743649836?pt=Motors_Car_Truck_Parts_Accessories&hash=item4605b7ea2c&vxp=mtr LED modules About $13 for 5.. cheaper than the 120 volt LED bulbs I bought that lasted a week.

http://www.ebay.com/itm/10A-12-24V-Auto-Switch-PWM-Solar-Panel-Battery-Charging-Controller-Regulator-/161023397383?pt=LH_DefaultDomain_0&hash=item257dbe0e07
Chinese charger controller.. $10.99

Battery came from Tractor Supply corp.. Can't trigger a memory of how much.

All works well, except I have not pulled the wiring into the walls yet.. strung along a upstairs wall testing it before I cut holes in plaster wall board.  I am wanting to build a free standing floor lamp to move them about. WE have discussed having a wire on the floor thou and tripping. AND falling..
I Hung a 24 foot Ibeam this morning in the ceiling by myself, programmed a Arduino this afternoon for a solar project, Helped a buddy out with a electrical motor connection issue on the phone, then cut up a chicken for Hotwings. I'd say it has been a "blessed day" for myself and all those around me.