I've just been having a measure up and I've discovered that I can fit two 100w flexible panels on my roof. If I get two panels is it simply the case that it will be twice as good as one panel?
Pretty much! You'll need the correctly rated controller. 200w/12v = the amps the controller should be rated to handle so that'll be a 20 amp model
Is its compatible to have a solar panel working on the roof when I could be on hook up, can or does it need to be isolated when doing this or does it make no difference, or would I just not need hook up if I had one fitted, I only run the fridge and lights
It all appears to look after itself somehow. No switching required. I,ve now disconnected my split charger as usually the battery is on a float charge and I suspect the alternator provides too high voltage for that. But somebody who understands better might disagree.
Just think of the panel as another charger, like the alternator or a Ctek. The tricksy bit is the charge controller which regulates how many amps go into the battery. If the battery is full coz you're on hook-up then the solar charge controller senses that & dumps energy from the panel. They usually have a heat sink built in so it's worth getting a good quality model of controller that has all the right bits & bobs...
I fancy this kit http://www.ebay.co.uk/itm/100W-Semi...738335?hash=item464022e0df:g:nykAAOSwl8NVX2Xh And this runs my electrics in the van http://www.ebay.co.uk/itm/PMS3-Camp...hash=item3ab878ba54:m:mVdwunjYaz1ZU-2VkYT8UwQ
@Woodster , the challenge we have in this country Woody is the consistency of sunlight hours. The panel needs to be in the sun/bright daylight & that's not always practical on a campsite. The second consideration is exactly how long you want to stay in one place without hook up. The fridge don't know the sun isn't shining & will continue to run regardless! If you're only 'free' camping in this sense for a weekend & are going to run the engine to make up for any deficit then solar should be fine on it's own....unless it's raining. options at least
For controller I asked @theBusmonkey for a recommendation because I just knew he'd have done the homework already. The one we have looks more substantial than the one in your linked kit and does 3 stage charging too. Check the the spec on your link.
That's a nice efficient and compact panel. The only issue is that if you want to upgrade & fit another in the future then you'll have wasted your money on a charge controller which is a basic model & can only handle 10 amps maximum. I'm afraid I don't know that model of PMS coz I'd rather have a Ctek smart charging the battery. In any case the panel won't interfere with it
I've been looking at solar and with an early roof with rear roof rack to actually fit in the roof rack I reckon I can only fit am 80w panel ... unless anyone knows where I can get a square shaped 100
Yeah. I would. For example ours are 180w total. This weekend me & pkrboo were messing about with figures & at one point he got just over 4 amps. That's pretty good from a 100w panel but it's a brief moment of sun from behind a cloud. We were consistenly over 5 amps and at one point got just under 9. OK Jonny Big B*)))*cks you say.... but that means our systems will run nearly twice as long (assuming they are the same draw etc) on the same amount of solar input than someone with a 100w panel. The cost of twice the output is less than double so it's a no brainer in that sense. @Bertiebot has one of these http://www.ebay.co.uk/itm/New-20A-M...246322?hash=item58d67704f2:g:GfMAAOSwe7BW0B41 which is a nice unit with the ability to interface with a remote meter (at extra cost). Ours & @zedders one is this (@sANDYbAY ) http://www.ebay.co.uk/itm/20A-MPPT-...037274?hash=item3cd64756da:g:za4AAOSwI3RW9i7K which has less bells & whistles but is slightly more compact. Also I can vouch that it's well built, has the correct internals a big heat sink & is more efficient than a PWM charge controller, ie it maximises the panels output by tricking it a bit to increase the voltage. It's worth getting the MPPT controller type when you're having higher output panels...
i have one of these http://www.ctek.com/gb/en/chargers/D250S DUAL It takes the alternator and/or solar panel power and charges the battery's as efficiently as it can, with the engine running it will control the loading on the alternator to charge the battery's as quickly as it can. you can get even fancier one that are used on boats but they start costing lots http://sterling-power.com/collectio...chargers/products/battery-to-battery-chargers Then when on hook up i have a ctex mxs5 http://www.ctek.com/gb/en/chargers/MXS 5.0
I have 100w but i'm expecting to find it's not quite enough when used for extended periods. I left room on the poptop for another.
i got mine for about £160 i didnt think it was to bad for a good solar controller and split multi stage charger
@theBusmonkey took the words from my mouth but I'll say it again anyway. Yep pretty much, more surface area = more power
Well these are the results of a bit of cutting and sticking I did today. The first picture shows two rectangles each the same size as a Baird 100w semi flexible panels. The panels cost £109 each and are 1240 X 570 X 2.5 and weigh 2.8kg. They touch in the centre and go right to the edge. The small square further back is the size of a cable gland box, 95mm X 115mm I cut each of the shapes down to the same size as a 100w 12v Energy+ semi-flexible Solar Panel -100w -TUV ISO UK. These panels cost £99.99 and are 1200 X 560 and also weigh 2.8kg. They are 10mm narrower so fit slightly better but there still isn't much room to spare and the outside edges are on the curviest part of the roof. I also tried these in a long line straight down the middle because along the centreline they will face the sun more efficiently but they are too long to fit without going over the sharp bend at the front of the roof. So a bit more searching turned up these ones called, 100w Flexible Solar Panel (back contact cells) for Camper, Caravan, rv, boat. They are more expensive at £129.99 but measure 1060 X 540 so smaller than the others and lighter too at only 1.9kg. So it looks like £260 as opposed to £200. But they will be less visible from the ground so probably a bit more secure from theft.