solar charging

[matty1275]

Hi All,
now i've got the cerb tucked up in a new garage rather than stuck outside,
I'm toying with getting a solar charger on the roof of the garage (no mains supply near the garage)

has anyone got any experience?
any idea on panel wattage?
reading up sounds like a 10w panel might be a reasonable starting point


cheers
matt

[Gazzab]

Had no power in a garage once do I put a solar charger in the garage window. Don't know if it made any difference really. But was the best I could do.

[optimax sniffer]

I've done solar charging before, but don't think that it does much. I think it they only just, supply enough juice to slow down the drain of the battery, but certainly won't charge it.

But I guess, of it means you can leave it for 5 weeks instead of 4....

[matty1275]

thats sort of what I thought. slow down the inevitable.

the basic 1.5 watt jobs must do nothing,
thought at least with a 10 watt job might see some benefit

[Bigadz]

These things need quite a bit of juice to crank so you'll have to get a decent one to stand half a chance.

[ShiDevil]

I tried this. Had it outside the garage door in full sunlight with a foot long by half foot wide panel. It was in a bin after a few days. My advice would be to stick with a mains trickle charger

[dean_ratpac]

agreed - tried one - just delayed the inevitable.

[Alpinestars]

Useless in my experience. How about jump leads onto a high amp hour truck battery. Prolongs the discharge by 2 to 3 times.

The truck battery can be brought back home to recharge as required.

[gruffalo]

A 10watt one would be pointless as will only give that power output in ideal conditions, get a proper panel, 80watts upwards will keep you battery in top notch condition but the panel costs £200 ish but as with most things you get what you pay for.

[K4TRV]

gruffalo said:

A 10watt one would be pointless as will only give that power output in ideal conditions, get a proper panel, 80watts upwards will keep you battery in top notch condition but the panel costs £200 ish but as with most things you get what you pay for.

+1 If you really want to know what a solar panel can do go here: http://www.motorhomefacts.com/modules.php?name=Sol...

For example a 10w solar panel in March will produce 0.3 Amps at noon (on a sunny day) which equates to 2 Amp/hours for 24-hours - a 60 Amp/hr battery will take 30-days, less what your alarm is draining it by!!

An 80 watt panel (nearly 3 foot by 2 foot) in March will produce 2.3 Amps at noon (on a sunny day) which equates to nearly 16 Amp/hrs - which could keep a 60 Amp/hr batt charged very well, on sunny days!!!!!

You pays your money...................

HTHs

Trev

[matty1275]

i've seen a 20w panel which i thought would give a trickle charge.
I know they aren't as good as an optimate, but anything is better than nothing

[K4TRV]

The calculator says a 20W panel will give:


Theoretical Maximum Panel Output: 0.6amps, at solar noon in March
Theoretical Daily Panel Output: 3.9amp-hours

Gets better as we move into Spring, by May its nearly 1.0 Amp and 8.8 amp-hours!!


Hope that helps?

Trv