Solar battery charger

Usel · Post by **Usel** » Mon Oct 29, 2018 10:35 am

Ok just looked at the solar panel battery chargers and they are pumping out about 0.2A. They will not blow the fuse for your lighter socket.

kis · Post by **kis** » Mon Oct 29, 2018 11:59 am

Okay fab thank you!

How many watts? The one linked is very similar to the AA one. Has a meager 2.4W would it be better to have 4W? 8W is deemed as boat territory so might be a bit much? Lol

Usel · Post by **Usel** » Mon Oct 29, 2018 12:10 pm

An 8W solar charger is still only 0.7A. I think the limit will be how big your dash board is

Status · Post by **Status** » Tue Oct 30, 2018 1:44 pm

Sounds like i have to have it on my dash which is no good as car is in a garage and I thought I could mount the solar panel outside on the garage door

Usel · Post by **Usel** » Tue Oct 30, 2018 1:57 pm

Status wrote: ↑Tue Oct 30, 2018 1:44 pm Sounds like i have to have it on my dash which is no good as car is in a garage and I thought I could mount the solar panel outside on the garage door

If your car is in a garage then why not use a mains powered trickle charger?

If you really want solar then get this:
https://www.ebay.co.uk/i/361482859520?r ... 0845709043

And this:

https://www.ebay.co.uk/i/332061473978?c ... edfff96723

ph001 · Post by **ph001** » Tue Oct 30, 2018 2:26 pm

Standby drain current from the battery with the car fully locked should be 10 - 100mA (depending on how much ancillary crap you have running) which equates to between 0.12W and 1.2W. So you need at least this to stop your battery going flat.

You have to remember though that the panels specified power is typically in direct full sun and that's not to common in the UK in winter, and of course you are only generating about 7hrs a day in December (the other 17hrs is discharge so you need to put around 2.5 times the current in compared to what goes out). A typical overcast day produces around 1/10th the quoted power so you should be looking at a minimum 30W panel + charge controller.

BeeEmm · Post by **BeeEmm** » Tue Oct 30, 2018 2:30 pm

Usel wrote: ↑Tue Oct 30, 2018 1:57 pm If your car is in a garage then why not use a mains powered trickle charger?

That's like saying "Why don't they eat cake". Lockup garages do not have power.

Usel · Post by **Usel** » Tue Oct 30, 2018 3:07 pm

BeeEmm wrote: ↑Tue Oct 30, 2018 2:30 pm
Usel wrote: ↑Tue Oct 30, 2018 1:57 pm If your car is in a garage then why not use a mains powered trickle charger?
That's like saying "Why don't they eat cake". Lockup garages do not have power.

Oh I see, well my suggestion of a 20w solar panel and a trickle charge will suit there needs perfectly.

Status · Post by **Status** » Tue Oct 30, 2018 4:54 pm

Don’t have power as it’s in my paddock,I put the garage up last year also the car won’t be locked and it won’t get nicked before anyone comments on that because of where it is

kis · Post by **kis** » Tue Oct 30, 2018 5:09 pm

Does it have windows?
Most solar car chargers are designed for "on dash" use as they're not waterproof?

Status · Post by **Status** » Tue Oct 30, 2018 6:15 pm

Yeah got a window but it’s facing away from the sun but might still be ok just wondered wot sort would be best

ph001 · Post by **ph001** » Wed Oct 31, 2018 3:43 pm

You'd defo need 30W minimum on the inside of a north facing window, even that might be a bit hit and miss to be honest. The panels output drops off massively in the shade.

Status · Post by **Status** » Thu Nov 01, 2018 12:48 am

I’m thinking I can mount it outside on the garage door and hope the lead will be long enough

ph001 · Post by **ph001** » Thu Nov 01, 2018 3:26 pm

Bit of speaker wire or two core mains cable and a couple of screw terminal choc blocks will sort that problem easy enough. I would defo recommend a charge controller like the one listed above as well though.

Jembo · Post by **Jembo** » Tue Jan 15, 2019 9:37 pm

How’s everyone doing with their solar chargers?

Started mine up the other weekend after nearly 4 months, span up really nicely, well impressed!!!

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