Solar Panels

[Ian and Jill Brown]

Hi All,

Previously we wrote regarding poor solar/battery performance in our Dec 07 TE.

It turns out that we had a fuse issue with the double bank of solar panels, that meant we were only charging off the single panel.

All fixed now.

We have decided to add the fourth Kyocera 130 watt panel, to give us that extra supply for the engel etc..

A few questons, if anyone has some advice on:

- Do we need the fourth battery, any advantages by having it?

- Are there any problems with four batteries in line?

- Do we need to upgrade the controller to a PL6 (have received contradictory opinions).

Any advice would be most appreciated.

Jill and I are due to leave Perth late in June for Darwin and back.

Hope to catch up with other Kedronners on the road.

Ian & Jill,

18'6" TE

[Rod and Mavis]

Hi Ian and Jill

Each 120/130w panel has a max output of approximately 7.5 amps.

This will put your max output at around 30 amps. If your current controller can handle 30+ amps you will be ok (min PL40).

Would suggest some expert advice on another battery. Your maximum usage and the endurance of the set up that you have needs to be considered.

You can wire up as many batteries as you require, all you are doing is increasing your amp/hours available. (time that you have power without charge)

Good luck.

Mavis and Rod :thumbsup:

[Ian and Jill Brown]

Thanks for your thoughts.

We will probably start with 4 panels and 3 batteries and see how we get on.

Ian

[Jacky Jacky]

Hi Ian,

We have 4 x 120 watt panels and 4 batteries. I'm not sure if you have heard of an author, Collyn Rivers. He wrote a book 'Solar that Really Works' which we purchased and then had a brief on-line discussion with him when he was on another forum. In the end we decided to have the 4th battery and panel as my family live in southern NSW so less 'sun hours' down there and we planned to spend time down that way. Virtually he said no good having all that solar coming in if you have nowhere to store it.

We also like to run our Engel fridge off the van at times.

Good luck with your decision.

[ATV42]

Hi there Ian & Jill

Hope this helps in your decision making process.

All solar panels loose various degrees of efficiency for a number of reasons. The prime loss is caused by shade on the panels; be it through overcast conditions, trees, time of day/ year, and even the positioning of the panels on the roof of the van e.g. if they are hard up against the roof mounted aircon some area will be shaded by the aircon during the day. No panel is 100% efficient!!!

You should also bear in mind that the solar input of flat roof mounted panels is directly related to your location and time of year. Roof mounted work extremley well around Darwin (12 degrees Latitude), whereas they don't work very well in Hobart (43 degrees Latitude). You could expect about 5-6 sun hours in Darwin all year :thumbsup: and about 6 summer, 2 winter in Hobart. In Perth you could expect 7.5 sun hours in summer and about 2 in winter. Idealy solar panels should be angled to the sun relative to the degrees of Latitude, but thats impossible in our caravan situation.

In addition to my 6x85 watt monocystalline BP panels (510 watt system), I have a portable setup consisting of 2x65 watt Kyocera panels, PL20 regulator, and 15 meters of lead. This allows the option of positioning the panels as required to charge my vehicle batteries or supplementing the caravan system if its in the shade; worth a thought!!!!

Are far as batteries are concerned, I would recommend the 4th. Mainly because of the reasons outlined above, and because you need to get as much 'power' into your batteries in the shortest possible time. Any extra power your solar generates will be lost if you can't store it.

I agree with the PL40 idea. You will need a shunt setup if you are wiring up the PL40 to read the load (output) of your system.

I certainly agree with the suggestion of getting Collyn Rivers book to learn more about solar systems in caravans. Its a worthwhile read.

All the best.

Peter

(ATV42)

[Ian and Jill Brown]

Thanks Peter & Anne for your thoughts.

I think we will go with the 4th battery.

The 4th solar panel was installed late this afternoon and will be out ín the sun' tomorrow.

Ian