Old car battery - can I use it with some solar panels and 12v garden lights?

danlightbulb

danlightbulb

danlightbulb

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As thread really. I have an old car battery which still works. Can I hook it up to power some garden lights and charge it with some small solar panels?

If so what do I need to buy?
 
danlightbulb said:
As thread really. I have an old car battery which still works. Can I hook it up to power some garden lights and charge it with some small solar panels?

If so what do I need to buy?
Click to expand...
Yes you can, I've seen numerous YouTube videos where they've done the same. Have a look at the videos to see if your up for it.
 
Yes i've got an old car battery in my shed powering the lights in that.

You need a solar panel and a charge controller, that's what you connect the solar panel and battery to, it then gives you an 12v output you can connect to whatever you like.

I used a cheapo one off ebay for about £10 and a 20w solar panel

Black lead coming in is from solar panel, the one from the bottom is the battery and the one going up over the ridge of the shed is the load to my lights.

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I bought a motorcycle battery that fits between my shed's beams and usually needs charge once every 3 years. Got it hooked up to a switch which is connected to 12V LEDs.
 
Sorry to bump this, I've been meaning to do this for years

Thinking of a meter² panel on the Shed at the end of garden

It's there a dumbed down guide here anywhere?
I'm a stats junkie so would like to send battery level and energy production to home assistant
 
Unfortunately the cheaper Renogy charge controllers aren't that cheap any more but I'd highly recommend them over the £10 jobbies - my dad has been using my old car batteries for shed lighting and they are still useful for years with a semi-decent charge controller, the cheap generic ones were killing batteries in months in some cases.
 
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I'm going to try getting an MPTT as I need the data
No data = Dull dumb project that I can't automate or send alerts

BTW note the video uses an inline fuse on the battery, is this necessary/ better fuse box to do it?
 
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Subliminal Aura said:
BTW note the video uses an inline fuse on the battery, is this necessary/ better fuse box to do it?
Click to expand...

It is rarely necessary but at the same time a good idea to do it - pretty much anything will do - except for the inverters where I'm using a higher amperage resettable "fuse" I use standard car blade fuses with either a 3-4 way block, inline or panel mount fuse holder as appropriate.

You don't need the MCB style stuff for just shed lighting, but if doing something a bit more complex and involving higher loads something more like that is required.

EDIT: Personally not a fan of mounting it all on a wooden/plywood panel when involving things like resettable fuses and inverters - though loads of people do it without issue - personally used metal pegboard panels in previous setups but that is because I had them to hand.
 
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Subliminal Aura said:
I'm going to try getting an MPTT as I need the data
No data = Dull dumb project that I can't automate or send alerts

BTW note the video uses an inline fuse on the battery, is this necessary/ better fuse box to do it?
Click to expand...

I'm a fan of the Victron stuff and they have a wide range depending on sizing needs, you can get the smallest SmartSolar MPPT 75/10 (75v and 10 amps) for around £40 (includes already protection on the output via fuse). The SmartSolar line has bluetooth comms to their app to show all the data (SmartSolar! Don't get BlueSolar, it doesn't have BLE) . I did a small project in car a year ago and added a SmartSolar 100/15 in, so essentially the same as the shed builds above except it has a detachable panel that we put on when we go camping. . I think with some bluetooth proxies you can integrate into HA but i've not bothered with mine since the panel is not connected most of the time, so while we are not camping its a glorified remote voltage reader for the car battery.

SmartSolar MPPT 75/10, 75/15, 100/15 & 100/20 | Victron Energy

Maximize the energy-harvest, driving it intelligently to achieve full charge in the shortest possible time using the SmartSolar MPPT. Learn more now.
www.victronenergy.com www.victronenergy.com
 
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Thanks mate I already had that exact model in my cart ... Going for the 100 | 20 (yes it's overkill but hey a little overhead is better than none)

I then started to look at Power Stations as an all in one simple solution but there seem to be a lot of quirks with them like USB outputs dropping power. I think I'll go with the leisure battery route and have a power station as an addon further down the line.

I'm also thinking of split charging with mains for the winter months but need to read up on that

Thanks guys
 
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