solar panels

[360david]

Im thinking about having a solar panel fitted to my swift escape. Would like some advice as to what amperage I should get. As an example of use I am off to Le Mans in June for the 24 hour race. That would be 5 or 6 days off the grid so as to speak.

Also cost the prices seem to vary quite a lot for the same amperage model. So a recommendation on supplier would be helpfull as well.

 

Many thanks

 

David

[colin]

It depends on your usage, for us a 85w panel in summer means we can be off grid indefinitely, we use lights, tv/radio, and water pump.

[thomsonjuk]

I have just put on a 100w panel and now in the process of adding another 100w rough costs below

 

typical 100w panel £70-90 I opted for the monocrystal as they are smaller

sikaflex 552 £20

mounting kit corners side and roof entry £35 includes cost of stainless machine screws and nylocs etc

controller pwm £10-30, I opted for a votronic mppt controller that would charge both starter and leisure battery £130, - initially overrated this so that i could add an additional panel if needed, this includes cost of a battery temp probe. as an extra also added in a solar monitor at £70, cable 6m of 6.0mm cable to connect controller to the panel, £20 also add for trim - half round conduit etc £10

comes out at around £375, then a day of my time fitting

 

monitoring the single 100w in winter i am getting about 4 ish amp hours per day,enough to keep me for a weekend off grid in the summer - off to Scotland this summer for 3 weeks hence the addition of another 100w just in case - but will probably find out that 200w is not near enough

:'(

[davidmac]

Hi if you are staying on the Beau Sejour campsite get yourself a generator, you could run it flat out all day and no-one will notice it. Been there , done it.

Regards David

[sshortcircuit]

You need to consider the reply Colin has given as it's all down to what your usage is. As David has alluded to, if your at a race track campsite then you will find generators are on all the time and nobody complains. Off to Spain next week for two months and I have a 90 watt panel and will not need a EHU as my energy usage is minimal. Hope you enjoy Le Mans.

[Matrix Meanderer]

If you do decide to install a solar panel I would recommend that you consider the new flush fitting ones that are glued directly to the roof rather than being mounted on an aluminium frame which is then glued to the roof. Ours is glued to the gently sloping roof leaving space for other fittings later.

 

http://www.solartechnology.co.uk/solar-panels/PV-Logic-FLEXi/PV-Logic-Flexi-Roof-Top-Kits?product_id=439

 

One great advantage is that being glued to the roof, it's a lower profile and cannot get muck, branches etc trapped underneath.

 

Well worth considering. *-)

[360david]

Thanks for the info. all very usefull. We go to Le mans every year but in the past have had tents having arrived in our various sporty cars. To old for that malarky now. So the Motorhome it is.

Anyone else on the forum heading down there this year.

Thanks again

David

[aandncaravan]

David, I would disagree with the value of a 'Flexible' Solar panel.

 

They don't have glass protecting the Solar cells, but either a plastic or resin based 'clear' panel.

You will have seen how Head light plastic 'lenses' discolour over time, so expect any flexi panel with a non glass pane to behave the same.

 

Obviously discolouration of the plastic 'pane' will reduce light transmission and power output.

Therefore suggest you carefully monitor the panels Solar harvest through it's life, so when it drops below 80% you can go back to the supplier under the guarantee to get it replaced.

Suggest written evidence of it's power drop over time might help with the claim?

 

 

Flexi panels can also suffer from overheating and premature failure.

All Solar panels work best when cool, so providing an air gap below them, by raising it 'off the roof' by a inch or two, helps them work more efficiently and last longer.

 

There have also been a few reports of Water getting below a 'glued direct' flexi Solar Panel that when it freezes becomes damaged by the Ice.

 

 

If you do fit a Flexi Solar panel, suggest you fix it in such a way that when power output does drop/fails totally it is easy to remove without tearing off the Motorhomes Ali skin?

 

Look for a Solar panel with a high quality glass pane. They are not all the same in terms of light transmission, even the best glass saps some light, thereby power output.

 

Note also that some of the lesser brands have reputedly been quoting power outputs without any Glass in place.

 

 

We don't do Solar anymore but the website has 3 webpages of independent help and advice : http://www.aandncaravanservices.co.uk/solar-power.php

 

This webpage : http://www.aandncaravanservices.co.uk/solar-panels.php shows how the same Solar setup in Cornwall can harvest almost 30% more than in North Scotland, just because of the lower angle of the sun in the sky as you go further North. That should give you a little idea of how much extra you will harvest at Le Mans?

 

Suggest you also think carefully about you batteries you use to store the Solar Power as their efficiency varies quite a bit.

 

I read the other day that a typical batteries efficiency can be as low as 80%, I think from a thread on here?, but the ones we recommend are nearer 95%. That efficiency gap usually widens as conventional batteries age.

See our Battery Technology webpage here : http://www.aandncaravanservices.co.uk/battery-technology.php

 

Solar Power can also give some batteries a harder life than others, again an explanation of 'why' on the webpages.

 

 

 

[360david]

Thats great in depth info. Thanks for taking the time to do that.

 

Regards

 

David