Temporary solar advice

Hello, just after some advice on a temporary solar set up. Mainly around fixing to the roof.

Off to Le Man's 24 he race mid June, unfortunately no hookup on the site this year.

Looking at Solar to keep the fridge running, and charge up a power station for 3 x mobiles and a speaker. I'd hope the power station would last three or four days and then can be charged from the 12v inside the van.

I'm not keen on drilling through the pop top roof, most of the time we have EHU on sites and worried a portable panel on the floor would get stolen when we are away from the van.

I was thinking about purchasing a flexible Renogy panel and whilst setting up attaching it to the roof using strong velcro and running the wiring through the front window underneath the wind deflectors.

The other option is to buy one of the traditional metal framed panels and attached the velcro to the metal.

Is it going to be much more beneficial spending a bit extra buying an MPPT controller over a PWM?

Thanks

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What size/type of leisure battery do you have? And how long are you going to need to run the fridge for?

Temporarily fixing a panel to a pop top will be a pain, tbh if you're going to the trouble of buying all the kit you may as well fix it on properly, there's plenty of options to not have to drill into your pop top.
 
What size/type of leisure battery do you have? And how long are you going to need to run the fridge for?

Temporarily fixing a panel to a pop top will be a pain, tbh if you're going to the trouble of buying all the kit you may as well fix it on properly, there's plenty of options to not have to drill into your pop top.
It's a standard leisure battery, reads 110ah from what I can see.

The fridge would be on for 6 x days. The first day would have around 7 hours driving.

I know there are options to attach the panel without drilling but it's the wiring that I can't see a way around without drilling.
 
Do you have barn doors or a tailgate? If barn doors, you can use the tailgate mount holes to get panel cables into the van.

MPPT Vs PWM is definitely worth it, they're about 30% more efficient.


A 100w panel, in bright sun, will output about 30Ah per day. A fridge at 1.25Ah/h is 30Ah usage per day...

If you had a PWM controller, that's down to 20Ah a day - have a couple of dull days with only 1 or 2Ah produced by the panel and you'll deplete the battery (or more likely, the fridge will shut off due to low voltage).

You do of course have the option of running the engine for a bit to recharge the batteries.

Also remember those semi flexible panels need to be kept fairly straight or else you'll end up cracking the cells.

If the panels have holes in the corners you can get suction mounts to attach them to your roof (magnets also but not suitable for a pop top)

Suction cups
 
You are proposing what we do - folding solar panel on roof with cables through partly open window to controller inside the van.
Just make sure that panel is secure - it does not take much wind to move it or fold it up.

Pete
 
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Stick a wire through your EHU with an XT60 plug (for DC) and wire to the leisure battery terminals. Then buy a cheapo solar stand alone panel with an MPPT built in.
 
Do you have barn doors or a tailgate? If barn doors, you can use the tailgate mount holes to get panel cables into the van.

MPPT Vs PWM is definitely worth it, they're about 30% more efficient.


A 100w panel, in bright sun, will output about 30Ah per day. A fridge at 1.25Ah/h is 30Ah usage per day...

If you had a PWM controller, that's down to 20Ah a day - have a couple of dull days with only 1 or 2Ah produced by the panel and you'll deplete the battery (or more likely, the fridge will shut off due to low voltage).

You do of course have the option of running the engine for a bit to recharge the batteries.

Also remember those semi flexible panels need to be kept fairly straight or else you'll end up cracking the cells.

If the panels have holes in the corners you can get suction mounts to attach them to your roof (magnets also but not suitable for a pop top)

Suction cups
That's some good info. Maybe I should look into a 200w or 2 x 100w panels.

I never thought about suction cups.
 
You are proposing what we do - folding solar panel on roof with cables through partly open window to controller inside the van.
Just make sure that panel is secure - it does not take much wind to move it or fold it up.

Pete
What panel do you use? And how do you secure it to the roof?
 
It's a generic 100W folding one from Amazon. Probably not available now.
I used small but strong magnets on the edges to hold it down (no pop top).

Pete
 
I'd definitely prefer an MPPT over a PWM, and definitely use MPPT for a permanent install.

If you are setting up a temporary panel for occasional use then if you go with the popular brands like Renogy the included PWM controllers are not terrible. The same is probably not true of the off brand eBay specials.

Thing is in a fixed install your panels are likely not well aligned with the sun so the greater efficiency of the MPPT gives you an edge. Portable panels you can set up well orientated to the sun and improve the efficiency that way.
 

I have just got this on Amazon with the £40 off voucher £129.99

had great online reviews and up to now, very pleased with the quality and output etc. Would recommend for your needs at Le Man.

We went to the Le man Classic w/e there last year and had a fantastic time :)
Thanks for that. I have got a couple of panels now. One is a foldable Renogy 80w, got it for £60 I think. Says refurbished, direct from Renogy. That will charge up a Renogy Phoenix 200 powerstation to charge all the phones and speakers etc.

I have also got a 130w Ecoworthy panel for £70 which I think I will put on to a sheet and velcro to the roof to see how it gets in before deciding on whether to fix permanently.

I'd like to try le man's classic. I'm guessing it doesn't get as busy as the main one. Le Man city is great which the tram next to the track
 
Has anyone seen the price for the new Renogy Portable Solar ? It seems cheap and I don't know why. Would this be a good set up if I'm not prepared to add solar to the roof yet ? 1000015793.png
 
Prices are dropping again after a period of shortages I think.

But yes a 200w panel from a well known brand is getting close to where folks find they can be self sufficient in the summer with reasonable management of the electrics. Even if you do decide the go with fixed solar it's still the sort of panel size that useful to deploy when you're at the van to get the most of the "free" charging.

As @TallPaul_S says if you're not charging something with a built in controller like a power bank or fridge with it's own battery you'll need a controller and a high current connection to your leisure battery like an Anderson SB50 - peak current from a large panel like that is too much for the usual "12v accessory" sockets.
 
Has anyone seen the price for the new Renogy Portable Solar ? It seems cheap and I don't know why. Would this be a good set up if I'm not prepared to add solar to the roof yet ? View attachment 241746

I purchased an 80w panel from Renogys eBay site, it was classed as refurbished but I can't tell any difference. Got it for £60 I think after making an offer.

I am really impressed with the quality. It comes with a carry bag and is really solid. I'm not sure how it would fair in rain as it has a cloth type backing.

For that reason I bought a 130w flexible panel which I am going to attach to the roof via flag bungees in the eyelets of the panel and a bungee under the pop top.

Not everyones cup of tea but I only need it for a week at Le Man's 24 hours motor race.

I can use the portable panel to charge the power bank and also use it at home to keep the leisure battery charged.

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Depending on how your leisure battery is charged the other possibility is to charge the starter and take the lead in under the bonnet like many do for the 240v EHU lead. If you have a DC-DC charger that works off battery voltage level rather than ignition that may be viable and cascade the charge onwards.
 
Yeah we bought the van and I'm sure the guy built it himself. The initial electrics weren't correct and the starter battery was being drained by the leisure battery when we were stopped. It was checked by an auto electrician and the starter is charger then the leisure battery through the controller (ABSAAR Controller). Had other work done recently with a reversing camera and the guy said the kitchen unit etc is solid and well put together so I'm loathed to start anything just now with regards to running cables lol currently on the NC500. I did have a plan to add a split charger etc to the EHU so it would charge the leisure battery (obviously getting the correct apparatus via information from the forum) but that's a future endeavour similar to the portable solar. I'm just looking to have stuff in place to make things easier if we end up without EHU, not that we charge much apart from phones and maybe a laptop.
 
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