Solar Powered Trickle Charger?

[sleepyfolk]

Anyone had any joy with one of these? I'm using the X at the midweek and at a weekend mainly, I do keep popping the battery on charge occasionally but it would be nice if one of those solar jobbies actually worked and kept it topped up, so any recommends out there or are they all sh1te  )

[X5Sport]

All the ones I have seen and used seem to fall short of expectations, mainly because they don't give good enough output to keep our big batteries topped up.  Those used by caravaneers might be better though 

If you can get close to a Jains supply then a battery conditioner would be better.  I use a CTEK 3.8A version permanently connected to a car in storage.  It cycles the battery every 10 days and keeps it fully charged up.  For charging the X6 (used only occasionally now) I use one of their 10A models.

[snrbrtsn]

I have similar traits allbeit, half the year the car sits on drive unused and only gets used every other month
A while back I bought a ctek charger, amazing things, February & October I put the battery through full charge cycle and seems to keep thing ticking over very well!
Said charge cycle takes about 16hours and returns battery to full health, (so far so good)

Ctek Mxs7.0 I believe

Never tried a solar charger though unsure if they'd have enough power to properly boost the large battery!

[Horizon]

[quote="sleepyfolk"]
Anyone had any joy with one of these? I'm using the X at the midweek and at a weekend mainly, I do keep popping the battery on charge occasionally but it would be nice if one of those solar jobbies actually worked and kept it topped up, so any recommends out there or are they all sh1te  )
[/quote]
I have read that the solar chargers/ battery conditioners are ineffective if placed on the dashboard inside the car, they are more efficient placed on the roof of the vehicle. One of my work colleges has a campervan and is looking into the plausibility of fitting a solar charger to maintain his battery. Maybe worth  trawling the caravan/ motorhome sites to get better feedback, as having an external solar panel
could be a security issue.

[henrym3]

I fitted a solar (flexible) panel in my sun roof.  Don't like sun roofs so therefore never use it nor do I ever slide the cover back, so its pretty much out of sight and only attracts comments if someone notices it when looking down from upstairs. I was having battery problems due to may driving cycle and have not had any since. It is an 80w and covers most of the roof glass one way and is tucked a little under the head lining the other way. My X would never sit for more than 5 days without use and it remains to be seen how it would perform in the winter. However I did fit one of those digital volt readers in the cig lighter socket to monitor things for a while and on a decent day having run the battery down to 11.6v listening to the radio, doors open etc. On shutting up shop and returning the next day around noon the volt reading was 12.2v. On a slightly different subject the digital volt meter in the cig lighter generally reads .1v more than the OBC. Because I've got one (CTEK) I do get tempted to hook it up now and again but have resisted up till now, probably will later in the year. As they say on Game of Thrones "Winter is Coming"

[sleepyfolk]

[quote="henrym3"]
I fitted a solar (flexible) panel in my sun roof.
[/quote]

Thanks for the replies, interesting stuff. I do put the smart charger on it regularly - it's got a new Bosch s5 in it so I don't want that ruining but it's not possible to leave it permanently connected at home.

Henry - I don't use my sunroof either and had thought about whether a flexible would fit up there (great minds and all that). Any chance of a link to the one you found, I found a 50w that would fit in but didn't see an 80. What solar regulator did you use? Is it hard-wired in or do you drop the cable down to the 12v socket when you park up?

[Upex]

What set up are you after specifically? I love solar installs, have a couple on the go at the moment, but there so many ways and options it's bloomin hard figuring the design vs easy to instal.

Biggest problem is that most glass has some sort of coating which greatly reduces the effectiveness of the panel/solar cells, so for best results, it either needs to be behind non blocking glass, or in the direct light. This then means that a smaller panel can be used for same output.

If your after a permanent instal, then the flat flexi panels are great. I've never mounted one to a roof or bonnet, (believe the car manufactures should be doing that and in fact some do) but there must be a way of gluing it on enough to prevent coming off at speed, especially if a lip edging is used to prevent wind getting underneath the panel.

If not so permanent then I've typically found ridgid panels fine. Had good results on the past using magnetic feat covered in anti slip matting (for scratch protection, not antislip), but if it's an all alloy body, magnets won't help. For steel bodies, this is a great solution, as can be mounted wherever best for the sun, doesn't always mean it's the roof depending on where and how parked.

If not steel, but have roof bars, a simple lightweight frame can be made to use the roof bars as mounting point. For alloy and no bars, another option is those sucker feet, especially the ones with the hand opperated levers, as means its well stuck on and wont move at all.

Cabling wise, a quick connection is the way to go. Far better connection than cig socket and more convenient. Ie directly connected to battery, fused and with charge controller or blocking diodes (ive used both before, just as a fail safe incase the controller lets go and saves me being stranded) neatly tucked away in trunk, with suitable tails to quick connect of a length that can reach out of rear boot hatch or side doors. Panel then has the other half of quick connect with shorter tail of course, to enable ease of handling. Stick panel on side, roof or wherever, open car, grab long tails and connect up via boot or door, depending where you've stuck the panel. Quick, easy and neat.

If the panel will always be in same place, ie roof, the long tails can be routed behind the trim and exit at the most convenient point. Of course if it's a permanent fixture, the wiring can be permanent to and hidden away all together. If a non permanent instal, ie magnet feet for roof, then if you glass allows some transmission, it can also have suckers on the front face, so can be suckered into glass when having it out in the open won't do, ie out for the day and want it there when come back.

The effectiveness will be driven by the size and quality of the panel. A small 10w will be pushing less than 1 amp in bright direct sun (assuming no glass block present), so if you've run your 140amph down half way (ie flat, as you can't and should drop below 50% or it'll leave this mortal earth very quickly) it'll take 70hrs of that direct sun to fully charge (assuming no further current drain at all, which is not the real truth), so it'll not be very effective at all. But a 100w pannel will do the same charge in 7hrs.

Clearly your not starting the beast if your battery is depleated to 50%, so this is extreme, but assuming a still severe 20% drop of battery, assuming it's a 140 amph, your down 28amp. If you get 4 hrs of decent day light, you'd need a 7amp per hour panel, so 84w in order to replace that 20% in the 4hrs. I think these figures far too large for a maintenance / top up application, but you get the idea. The size will be driven by battery size and it's depletion vs how much light (or more accurately how quick you need that capacity restored).

Be interested to hear and see what you do go with, but if done properly, they are worth it. It's also not as expensive as you may think if shop savvy, panels are way down in price verses few years back and diy vs shop bought solution will give you a lot more for your money!

[sleepyfolk]

Well like all these things it starts with a simple trickle charger to help out but I'm prepared to fit something in a bit more permanently if it works, be nice to have a decent panel up by the sunroof

[Upex]

Lol, why the heck not.

You'll get a lot more out of a better instal, permanent or not, and will help get more life out of a battery so will pay for itself in the long run lol. Not to mention peace of mind and better reliability.

I say do it!

Couple of smaller panels directly onto sunroof glass. Cable through hatch (sealed in a fashion of course, don't want no leaks) and wired down under interior trim, perfect. Just remember to disable the sunroof, so it's not opened by accident.  )

[sleepyfolk]

Here's hoping Henry will come back with some info or photos, measured up tonight, I reckon it's now officially on the to do list. Need something to do whilst I'm waiting for my instalube to arrive from the US, mind you I do have the passenger door handle to fix as well!

[Upex]

Instalube.......  )

[sleepyfolk]

[quote="Upex"]
Instalube.......  )
[/quote]

) calm down, not that sort of lube! 

[Upex]

) calm down, not that sort of lube! 

>:D He he  O:-)

[DJ_x5]

I use a generic Maplins solar trickle charger on both the X5 (E53 3.0d) and my M3 (E36 3.2). The M3 seems to do absolutely fine regardless of the time in between usage. The X5 will be flat if more than say 2 months passes but that's usually more than adequate for me. I work away a lot hence the limited usage

[sleepyfolk]

[quote="DJ_x5"]
I use a generic Maplins solar trickle charger on both the X5 (E53 3.0d) and my M3 (E36 3.2). The M3 seems to do absolutely fine regardless of the time in between usage. The X5 will be flat if more than say 2 months passes but that's usually more than adequate for me. I work away a lot hence the limited usage
[/quote]

What size panel do you use?