Jump to content

Solar Panel


Caballero
 Share

Recommended Posts

Hi Guys

 

It's probably been done before but i'm looking in to buying a Solar Panel not looking to spend hundreds just want something to top up the battery when on the odd rally and site without ehu.

 

I know my battery will probably last over a weekend but I do like my gadgets and need to charge them on a regular basis.

 

So what to buy and rough costs would be great.

 

Regards

Phil

Link to comment
Share on other sites

I use this panel HERE which I put in the rooflight. I bolted on a couple of aluminum flat bar legs to help hold it in position. This supplier does some different physical sizes so choose one that will fit your into the rooflight.

 

The 20 Watt panel I find is good for when the van is in storage, for rallying I personally think you need bigger panels to get more charge back into the battery so I went for and use happily a 150 watt folding set (2 x 75 Watt panels) HERE. To put into perspective, the 20 Watt will give you around 1. 5 amps on a really good sunny day, whereas I can get 10 amps plus using the bigger set. Both these figures drop considerably when clouds are about.

 

You can place in the front window instead but I prefer to have mine hidden from view.

 

It's better to run a panel through a solar charge controller so you don't boil your battery, I went for this one HERE as it does the smart charging cycle, it's bloomin expensive but a cheaper alternative could be something like this HERE.

 

I would suggest a minimum of a 15A controller. these cheaper controllers don't have the full on smart charge function but will sense when the battery is getting full and reduce the charge current accordingly.

 

I'm sure others will have a different view and may have done something that performs equally well for cheaper.

 

Hope this helps.

Edited by Trevski
Link to comment
Share on other sites

Hi,

Agree with most of the above though if the penny's run to it i would suggest that you go for a semi flexible monocristaline as these give the best ( at the moment ) output but the difference is small though the weight saving over a glass panel is quite a lot, plus should they fall the glass can crack ( seen quite a few at rallies-- wind blows them over ) output -- bigger the better ! ( winter - output can be down to 1/3 of summer plus shorter days )

Regulator- again get as good as you can afford-- don't forget the fuse ( in battery + lead from regulator ) in case the regulator goes "belly up " & put the regulator as near the battery as possible thus reducing the cable resistance- this can fool the regulator.

david

P. S. Semi flexible panels are ( usually ) made on an aluminium back plate - you can walk on them ( with soft shoes ) If you plan to leave it near the towbar get some means of securing it --- panels tend to " walk " !

Skoda Scout 4x4 pulling a coachman Amara 520/4 at 93%---- when full!

Link to comment
Share on other sites

For an instant fix with no diy involved we bought an 80W (2 x40W) folding suitcase affair which we just plug into an extra fused lead on the battery. Ours cost £150 and came in a padded bag with a controller and a lead.

 

Depends what you want. .......

2007 Bailey Series 5 Senator Arizona (4 berth, rear bathroom, side dinette) towed by a 57 Kia Sorento XS Auto with Kumho KL17 tyres, Reich Mover, Kampa Rally 390, Caravan Tyres : GT Radial Maxmiler CX 185/80 R14 102R.

 

Link to comment
Share on other sites

On the Subject of Controllers, when selecting one, Could I buy a 30A Controller now and use it with a panel which only supplies 5-10a or should you use a controller which is nearer the output of the panel?

All I'm looking at right now is that for Long Weekends I'm thinking a 150w panel should be more than enough to keep us going but I later, if I choose to take a week or two off grid then can I have the option to add another panel to a higher rated Controller without any side effects?

2011 VW Touran 1. 6 TDI DSG7
2011 Lunar Conquest 544
88% Match.

Link to comment
Share on other sites

Actually a good idea and yes you can do that. There are 2 types of technology that controllers use to try and maximise the solar yield from panels. PWM and MPPT, the latter is the "newer" type and the one I would look for.

 

Some of the eBay cheap controllers are PWM only, you do get what you pay for. It's also worth noting that some of the bigger panels come with their own controller and are not always compatible with a second one.

 

In the case of my 150W panels, I simply bypassed the one supplied with the panel and then connected my panels directly to my CTEK controller.

Edited by Trevski
Link to comment
Share on other sites

Hi

Further to the post re controller--- dont buy a panel with the controller on the back, just about the worst place for a controller ! ( heat & a long way to the battery ) in the case of a glass panel on a hot day -if you put your hand on the back you will soon understand ! :o

david

Skoda Scout 4x4 pulling a coachman Amara 520/4 at 93%---- when full!

Link to comment
Share on other sites

Thanks Guys

 

I really do have something to think about now.

Link to comment
Share on other sites

I simply bypassed the one supplied with the panel and then connected my panels directly to my CTEK controller.

Can you provide the CTEK model/version information for this type of connection.

Ford C-Max and Coachman Festival 380/2 SE 2006    Motto  Carpe Diem

Still trying to find the perfect pitch. ..110 amp Battery+ 65 watt roof mounted Solar and 25 watt Wind Turbine. LED lighting. Status Aerial 315. Loose chattels marked with UV,. Safefill Gas Fitted.

 

Link to comment
Share on other sites

Regarding controllers they're the important part of the system, the old type were shunt, they just turned on and off at a set voltage.

 

Then came the pulse width modulation (PWM) this was the most advanced charger at the time, morningstar had the patent. however not all PWM systems work the same & there are still cheap copies available also shunt controllers can be put into a posh box which states PWM (youtube shows more info on fakes).

 

If you want to learn more on PWM heres a link http://www. morningstarcorp. com/wp-content/uploads/2014/02/8.-Why-PWM1. pdf

 

Then came the mppt controller (maximum point point tracking) the most efficient controller yet.

 

Controller are like cars & you get what you pay for, unfortunately controller have all the parts hidden in a box & its impossible to tell whether its a real Rolls Royce or a Reliant Robin with Rolls Royce badges. My advice is to buy from a reliable source.

 

A proper MPPT can be a lot of money, sometimes it works out cheaper to increase the the size of the solar panels

 

This link explains more about things solar http://www. windsun. com/

Paul B

. .......Mondeo Estate & Elddis Avanté 505 (Tobago)

Link to comment
Share on other sites

Caballero

 

There is a company called Selecta in Shady Lane Great Barr, about 10 miles from you, they advertise in CC&C mag, I brought a complete 130 watt kit for £249 excellent product with all the better controllers and mounting brackets, heavy duty cable etc.

Link to comment
Share on other sites

Can you provide the CTEK model/version information for this type of connection.

CTEK D250S DUAL 12V 20A 6 STAGE DC/DC SMART BATTERY CHARGER

 

I'm happy to put together a schematic of my system and post up the drawing if anyone would find it useful?

Edited by Trevski
Link to comment
Share on other sites

CTEK D250S DUAL 12V 20A 6 STAGE DC/DC SMART BATTERY CHARGER

At £186 I expect that will do the job very well.

 

Not your normal CTEK ;)

Ford C-Max and Coachman Festival 380/2 SE 2006    Motto  Carpe Diem

Still trying to find the perfect pitch. ..110 amp Battery+ 65 watt roof mounted Solar and 25 watt Wind Turbine. LED lighting. Status Aerial 315. Loose chattels marked with UV,. Safefill Gas Fitted.

 

Link to comment
Share on other sites

any of these semi flexible kits on the bay any use? HERE

 

I see lots of kits but i am confused with it all. Lets face it everyone will say theirs is the best.

 

I dont think i will need tons of power and most of our longer stays will be on EHU. But 2 days weekends we intend to be without EHU and want to last without taking the battery below 50% charge.

 

my calculations say i will get through my 75aH battery in a day at expected useage so a 60w would probably do me over 2 days

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

2015 BMW 330d Touring Xdrive pulling A 2014 Bailey Unicorn S2 Cadiz

Link to comment
Share on other sites

On a nice summer day of sun with no cloud in theory you should produce just shy of 5 Amps an hour from a 60 Watt panel, working on 6 hours of sun that's only 35AH you'll put back, in reality it will be less as your solar controller will throttle back the charge current as the voltage in the battery rises. So maybe 20 - 30AH.

 

So you'll be starting day 2 closer to your 50% battery discharge than may be comfortable.

 

If you get a cloudy day you will be lucky to get 1 Amp an hour so I'd consider doubling to 120W of panel or even 150W to get you through the cloudy scenario.

Link to comment
Share on other sites

What do you think to this

 

http://www. ebay. co. uk/itm/100W-Folding-Solar-

PV-Panel-MonoCrystalline-Kit-Charge-Controller-Croc Clips/261083667740pt=UK_Gadgets&hash=item3cc9cc9d1c

 

That's the one that we have for the last two years

2004 land rover discovery 2 td5 with a 2008 twin wheel compass rallye 636

Link to comment
Share on other sites

Its showing ok in my watching list.

 

Seems ok off my link

Edited by Caballero
Link to comment
Share on other sites

On a nice summer day of sun with no cloud in theory you should produce just shy of 5 Amps an hour from a 60 Watt panel, working on 6 hours of sun that's only 35AH you'll put back, in reality it will be less as your solar controller will throttle back the charge current as the voltage in the battery rises. So maybe 20 - 30AH.

 

So you'll be starting day 2 closer to your 50% battery discharge than may be comfortable.

 

If you get a cloudy day you will be lucky to get 1 Amp an hour so I'd consider doubling to 120W of panel or even 150W to get you through the cloudy scenario.

 

 

The issue then goes from wattage to Physical size and roof space. I would probably be better getting 2 60W units

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

2015 BMW 330d Touring Xdrive pulling A 2014 Bailey Unicorn S2 Cadiz

Link to comment
Share on other sites

The downside to roof mount is that you are not presenting the panel to face the sun so performance is reduced again, compared to leaning a couple of panels against the van and moving them to track the sun a few times a day.

 

It's easy to get carried away with this solar lark, if you are going to roof mount then maybe put a waterproof junction box up there, if you find you want to add more panels (same wattage) then you can wire them in parallel at the junction box.

 

The other side of the coin is to reduce your 12v need, so replace light bulbs with LED ( approx a third of the power consumption ) maybe increase the size of battery to 100 or 120AH, change TV for a 12v LED one.

 

It's finding the balance of need v cost v benefit.

Link to comment
Share on other sites

For summer use mounting them on the roof is not much of a "down side" as the sun is high in the sky. Traking for optimum yield has its downside, you have to be there to do so, and if not could easily get a lower yield than leaving it on the roof.

 

I have an 85 Watt free standing panel, but the choice of being freestanding was largely motivated by off summer use where optimum performance is important. In summer there is normally an overkill of performance, and they gather energy for a lot more than the 6hours mentioned earlier. In summer I place mine at an angle of 15 degrees to horizontal on a South bearing, and leave it like that whilst out making the most of the day.

 

In winter it is set at 50 degrees and tracked which requires a lot of being there. In winter its yield can swing from the occasional exceptional, when its very cold but crystal clear to the more usual inadequate when its endless grey.

 

Edit: A significant mistake I see made a lot of the time is they are placed on the ground in a manner where grass throws shadows on at least a few lower cells. With the several panels I have been involved with this has a totally disproportionate effect on performance. Mine go on a pegged out square cut from an old ground sheet, standing the base on a purpose made wooden receiver. Most commercial panels are all to easy to stand in grass and the owner left to know no better. Here, laying them flat rather than stood in grass must be quite a help.

Edited by JTQ
Link to comment
Share on other sites

A picture of mine from when I had a crt telly & freeview box, with the led tv I only need the 50 watt panel :)

Pictures from phone 025.jpg

 

Paul B

. .......Mondeo Estate & Elddis Avanté 505 (Tobago)

Link to comment
Share on other sites

That's the one that we have for the last two years

 

How do you get on with it? do you manage a weekend rally without EHU?

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

2015 BMW 330d Touring Xdrive pulling A 2014 Bailey Unicorn S2 Cadiz

Link to comment
Share on other sites

I solved my problem of not getting enough from my old 40 watt unit by roof mounting a whopper 250 watt one. LOL. No probs now even in the depths of winter \I still get 5 or 6 amps. Coupled witb 2 x 110amp batts, my wife loves the freedom of the kettle and the telly on all day with the hair dryer and the occasional charging of phones and the like. who needs ehu anyway.

Im back to motorhoming with a scooter on the back again.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Restore formatting

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

 Share

×
×
  • Create New...