Solar panel advice please ?

essJ

Guest
Hello all.

With so many suppliers advertising solar power, can anyone recommend a solar panel installation they have used please, i.e. type and supplier of panels and regulator ?

I have 2 x 110 Ah LB's and run a 240v fridge from an inverter (not pure sine wave). I have a split charge system from the alternator and was intending to add 100w or perhaps 200w solar to keep the batteries topped up. We usually move on after no more than 3 days.

Any thoughts/advice gratefully received.

Thanks, SJ.
 
120 or 140 watts should be fine

essJ said:
Hello all.

With so many suppliers advertising solar power, can anyone recommend a solar panel installation they have used please, i.e. type and supplier of panels and regulator ?

I have 2 x 110 Ah LB's and run a 240v fridge from an inverter (not pure sine wave). I have a split charge system from the alternator and was intending to add 100w or perhaps 200w solar to keep the batteries topped up. We usually move on after no more than 3 days.

Any thoughts/advice gratefully received.

Thanks, SJ.
Click to expand...

We had a 120 W system installed for£370 (liverpool)
You can probably get cheaper
Make sure you get a MPPT contoller
 
Your inverter is going to be using power even when the fridge is not. It's one of the biggest problems with inverters. You need to know what the power consumption for the fridge is and what size inverter you are using. Solar panels work best pointing at the sun but this is not possible so you loose a good percentage of power by not having them at the optimum angle / direction.

..
 
Invertor

I have heard some invertors use power even when not in use !
So get one you can plug/unplug (leisure battery)
 
jagmanx said:
I have heard some invertors use power even when not in use !
So get one you can plug/unplug (leisure battery)
Click to expand...

Biggest problem with a fridge is that you don't know when it's going to need power. Some inverters can consume a considerable amount of power ( 4 amps for some ) when not doing anything. This is one of the reasons why you should match the inverter to the load. There is no point at all in just buying the biggest inverter you can afford and only charging up your mobile phone.

Only way you find out is to work out the loads.

2 x 110 amp batteries will give you 110 amps of juice before you ruin a battery an inverter is usually 85-95% efficient but you only get towards the 95% when you are using optimum power. So you have about 93 amps left. A 200w Solar panel will give you about 12 amps on a nice sunny day so it's going to take about 10 hours to put back 110 amps. With a 100w panel it would take 20 hours. With a cloudy day who knows.

Good article Here

You could of course add a wind generator and get even more power.

It would be helpful to know what kind of fridge and what the average power consumption is.

..
 
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jagmanx said:
We had a 120 W system installed for£370 (liverpool)
You can probably get cheaper
Make sure you get a MPPT contoller
Click to expand...

Not always good advice I'm afraid.

Some systems do not like them.

One example is the Electroblock. Certain models need the Schaudt LR1218 solar regulator, anything else is not recommended. The LR1218 is a dual PWM regulator (charges leisure AND van batteries) but is nevertheless a very good one. I have managed without an MPPT controller for a lot of years now.
 
My rule of thumb is 1watt of solar power per 1amp of battery.
Change your bulbs to LEDs and mounting your panels so you can tilt them helps. As does getting a haircut.
 
Go for 200w of panels if you can, as your fridge will be the big consumer. We had a 120w panel, two 95Ah batteries with a compressor fridge and it managed. I have now put another 80w panel on and now never see batteries below 12.4v , but that will depend on whatever else electrical you use.
 
Photonic universe, they sell all the controllers, mounts, etc, Bosch panels, mine kick out about 21v on single, 45v on double on a reasonable day, the controllers only send whats required to the batteries. These are diy kits, not sure if they do installs, they advertise on fleabay, although kits are packaged by amazon so probably on there aswell.
 
carol said:
Good article Pat but why is he talking himself out of business?
Click to expand...

Perhaps he doesn't feel he can guarantee panels, So would rather not lose customers
fitting panels that he feels are of poor construction and not fit for purpose.

Also if the op moves every 3rd day if it wasn't for his fridge he wouldn't very likely need solar I have a similar battery's and haven't found the need for it perhaps a gas fridge would be a better option.
 
Fazerloz said:
Go for 200w of panels if you can, as your fridge will be the big consumer. We had a 120w panel, two 95Ah batteries with a compressor fridge and it managed. I have now put another 80w panel on and now never see batteries below 12.4v , but that will depend on whatever else electrical you use.
Click to expand...
I am reliably informed that the panels must be the same or the output of the bigger one will reduce to the value of the smaller. ie 100 plus 80 is equal to 160 not 180. Do not know why and I am now worried that the output of the solar will detract from the alternator and I will loose out on engine charging.
 
carol said:
Good article Pat but why is he talking himself out of business?
Click to expand...

I think a lot of folk expect too much from a 100w solar panel and I think also that he's the kind of guy that isn't prepared to sell or fit something that won't come up to customers expectations. He's a pretty straight talking, no bullshit kind of guy. Then again maybe there's not enough profit for him in fitting panels. I've got a 100w panel on my van and I find it useful but I know it's limitations. Would I fit another one if I bought another van? Probably not. If I drive during the day it tops up the LB for me. If I park up for more than a few days I'll look for somewhere with EHU. Unless I'm in Greece, which I will be Thursday :) , and the Suns belting down all day.

Pat
 
jagmanx said:
I have heard some invertors use power even when not in use !
So get one you can plug/unplug (leisure battery)
Click to expand...

All inverters use power when no load is used!!

Usually, the larger the inverter, the higher the quiescent current (current used without a load) usually in the range 0.5-1A, then there's the efficiency say 75% at less than max output.

If you must use an inverter, it can be better to have say two, one for low power equipment and one for higher, however, devices such as fridges need a huge surge to start them up to 4x the running power. Turn off whenever you are not using.
 
As people seem to know about invertors i have an 8000w LF type one, 32000w surge, 8000w constant, which i will be running off 4 135ah LBs linked as 24v, charging with 2 120w solar panels linked as 24v. According to the bumpf that came with it its meant to be 95% efficient with virtually no current use while on standby, its also usable as a 20amp battery charger while on mains or generator. Its massive, 3' long, 1' wide, 6" thick, weieghs about 40kilos, do you think ive over done it? I was told pretty much the opposite to what everyones saying, that i should get the biggest i could afford as it will be more efficient because it wont have to work very hard, which makes sense to me. LF type are also supposed to be more efficient than HF, which the majority are. Anybody any thoughts?

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Stu709d said:
SNIP
I was told pretty much the opposite to what everyones saying, that i should get the biggest i could afford as it will be more efficient because it wont have to work very hard, which makes sense to me. LF type are also supposed to be more efficient than HF, which the majority are. Anybody any thoughts?
Click to expand...

Wasn't April the First last week?
 
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