DIY Caravan Solar panel
How to install a solar panel to your caravan or motorhome
Your obviously interested in fitting your own solar panel, so before we get started i just want to say, this project is not that difficult if you follow a few simple steps and plan out the work before you start, your probably going to have a different caravan to the one I own therefore the install will be slightly different but the principles will be the same and in my opinion you will get a better set up by doing it yourself.
Why bother fitting it yourself
Quality, but not only that you can pick and choose the panel and the controller. I had quite a few quotes from various caravan and motorhome dealers and they all wanted to fit there panels with there controllers, well I'm sorry but if i am forking out 600 quid for a solar panel then i want to choose all the equipment myself, this is the main reason for the self fit so i could choose exactly the equipment I wanted and believe me its a bit of a mine field when it comes to buying the bits.
I have spent many hours searching for the best system for the £400 budget I had. Did I find a good solar system for my caravan ? you bet your ass i did.... Ive had it installed now for 2 months and its fantastic I can honestly say i don't need electric hook up anymore...
What did i go for ? I opted for a semi flexible panel mainly because of the weight some solid panels come in at around 10 kgs mine came in at 3.15 kgs size is 1445 x 540 x 3 mm, is a hefty weight saving and these new back wired panels give out extra 25 % power also made from a very robust material to the point that they are advertised they can even be walked on, i suppose time will tell and i will definitely not be walking on it, but it does feel strong and can see it lasting the time of the caravan. ok so why 150 Watts this is very difficult to predict how much power your going to need to keep that leisure battery topped up because everyones needs are very different, here is my example. I have wet central heating which requires a pump to be running this only draws 1 AMH and when up to temperature only kick in and out occasionally, we like to watch quite a bit of TV my telly and booster burns again 1 APH which is not that significant (BTW I have a 115 AMP battery) all my lights are LED and we have 2 showers per day. Your internal lighting, I think most of us running off electricity are not going to have all the lights turned on all night so again we perhaps just leave 1 x reading lamp on which is aprox 1 watt. I think you are getting the picture of our usage and its probably not that different to yours. So having done loads of research on panel size per panel output per panel value for money this came out on top for me and my requirements.
MPPT Charge Controller
Maximum Power Point Tracking controller (Tracer) by photonic Universe was my choice of controller, this was included in the kit which was a bonus, this controller is re badged by other dealers but its the same, Its fully automatic recognising your battery power EG 12v or 24v in my case 12v, its works on 3 stage charging recognising the battery condition and pulling the correct amount of power from the panel and has an array of built in safety features,
another nice feature is the led front panel which shows you the condition of your battery and how much power the panel is producing at and one time, I also like the remote screen you can install, flush mounted and looks nice. this
remote wired screen gives you other features which you can play with. The main controller was fitted under the seat so was difficult to read the screen so this optional extra is a great addition.
- 150w Semi flexible solar panel
- MTTP Tracer charge controller
- 2 x Extension cables with fitted MC4 connectors
- 5 mts of 4mm battery cable
- MT 50 remote Tracer desplay
- Battery isolation switch
- CT1 adhesive
- CT1 multi solve degreaser
- Inline Blade fuse holder
- 30amp junction box
- 4 x modesty cabinet blocks
- water proof cable entry gland
- 8mm + 2mm metal drill bit
Plan It Out
Plan every step !
Its all about the cables, I positioned my panel above the tall wardrobe which gives me the option to connect the extension cables out of sight in the wardrobe and also gives me a way down under the caravan again out of sight.
my controller was positioned in the locker next to the motor mover control box because there is an external door which makes it easy to isolate the panel using the isolating switch, another good location is under the seat next to the battery box, work out the cable lengths that you have and don't worry if there short as longer extensions are available. Your inline fuse protection (20amp) need to go between the controller and the battery so mine was positioned next to the battery box.
I managed to position the remote MT50 screen next to the caravans main control panels which looks great, there is a corner cable cover with other cables running downwards i managed to clip this off and hide the MT50 cable in.
Glue The Panel Down
Ok you have planed it all out its now time to bond the panel down. there are various glues on the market that will do the job i went for CT1 as I use this at work, its high quality Excellent resistance to chemicals, Antifungal, Prevents bacteria growth UV resistant, Excellent resistance to vibration, Odourless, Does not shrink, Can be painted, Contains no solvents, No isocyanates. Works in wet or dry conditions, Can be used in all salt-water environments say no more... I also used CT1 (CT1 REVIEW) degreaser as I have used this on various jobs its non aggressive and in my opinion gives you the best surface to bond to. Sikaflex is also a very good bonding agent which will do the same job its just personal preference.
These flexible panels need to be bonded down in a way that gives you 2mm air gap between the caravan roof and the underside of the panel, this is done my applying the adhesive in 10mm beads with gaps between the beads this allows water and air to escape, you need to make sure when you push the panel down that the beads of adhesive don't squash together. I put the panel into its final position and then draw round the panel with a pencil then i applied the adhesive as per the picture then using a dry paint roller pushed the panel onto the adhesive, if you look under the panel one bonded down you can just see light under it..
Water proof entry gland
You will start to get a bit nervous with this step as it requires you to drill a hole in the roof of your caravan !! don't be its a piece of cake, I went inside and measured inside the wardrobe and double checked my measurement outside and drilled a small 2mm hole first then increased the size to 8mm, I cut off the 2 x mc4 connectors push the solar panel cables through the gland then through the caravan roof tighten up the gland nuts and seal inside with sealant and also squeeze some into the hole and bond the whole gland down to the roof with the nuts facing the back of the caravan and i held it in place with some making tape until the next day. I also used some stick down cable clips to hold any excess cable to the caravan roof..
I positioned the controller in the locker under the bench seat next to the mover control box this gave me access from inside and out side the caravan the only problem I had was getting the cable from the solar panel to the controller, my only choice was down through the bottom of the wardrobe under the van and back up in the locker where the controller is sound a nightmare but this took me 10mins, use the extension cables now and drill 2x 8mm holes in the bottom of the wardrobe floor thread the cables down leaving enough to connect onto the solar panel cables you have dropped through the caravan roof, now using a few cable ties fix the 2 x cables to any existing cables you find under your caravan and either drill 2 more holes in the floor next to the controller or do what i did and manage to get them through an existing cable entry point. (don't connect to the controller yet) you first need to sort out the isolation switch and get the battery cables over to your battery box.
Solar Panel Isolation Switch
This is optional you probably will not ever need one but I put one in just in case again very easy i put on on the live feed from the panel before you connect to the controller. For this i used a battery isolation switch the same as the one to turn the mover on and off, very cheap and very easy to fit. I just simply used some crimps that I had in the garage to make life easier, as you can see i positioned the isolation switch next to the motor mover isolation.
Next step is the battery feed from the controller to your battery box, I managed to run the cable inside the caravan under the front bench seats behind the front chest of draws to the battery box. At this point you need to add a fuse (20amp in my case) I bought an inline spade fuse holder from Amazon and a 30 amp junction box and wired up the fuse holder to the live feed just before it enters the back of the battery box. I drilled another 8mm hole in the top of the battery box and thread the cable in, I then used 2 x crimps and connected to the quick clamps on the battery.
Connect It Up
Now there is a sequence to the connecting stage, you first need to connect the battery leads to the charge controller there are at the bottom of the controller and then connect to the battery, the controller will then recognise the battery and then your good to go with connecting the leads from the solar panel, if its still daylight you should start to see some action on the led screen and thats basically it, now I've read this back it does sound complicated but its not if you plan it out first and all caravan are different and remember there is no problem running cables under the caravan as thats where all the main caravan cables are run these days and its a great way to hide any wires, always remember to fill any holes you drill and any the manufacture forgot to.
If like me you like going off grid or you like caravan or motorhome rallies a solar panel is a great investment, my 150w panel keeps my battery topped up and i don't have to lug heavy batteries around and because its on the roof I've no portable solar panel to find room for either not to mention the security aspect of having one bonded to the roof.
My next post i will go into more detail with regards to the MT 50 remote screen i fitted to my Charge controller again this is optional but its great to see all that lovely sunshine power going into you battery..........