Solar panel advice

[AndyWT]

Ok so I’m firmly on the side of “no point”

I can manage four days with fridge (ambient depending obvs)

I couldn’t find any cold hard facts in this post about it’s capability.

let’s assume I have discharged my leisure battery to less than the required level to run the fridge.

Assume average UK weather and for fun, let’s assume I’ve been pitched by a CCC Hi viz muppet , so no choice on orientation.

Given that to charge a battery you need more than 12v etc.......

Will I be able to plug in the solar and carry on as before. ?

You have hit the nail exactly on the head

“Will I be able to plug in the solar and carry on as before. ?”

I’m pro Solar but! No one can answer that, there is no standard solar setup, there is no standard weather, there is no standard power consumption.

How long will you be without shore power? A weekend worrier can usually survive the until home.

Let’s look at the variables,

Panels 100-200W ? flexible or rigid
Voltage 12 or 24V nominal, actually 18 or 36V at full sun
Controller PWM basically a variable period switch, MPPT works like a variable Volt/Amp inverter and is required for 24V panels or 2x 12V in series
Size of cables ideally/hopefully min 6mm sq, length not an issue on a van.
Panels horizontal
Panels on raised pop-top, assuming it’s parked nose North
Shaded panels
Weather?

And unless you have a battery to battery charger an alternator cannot fully charge a battery, whereas solar can especially with a MPPT controller.

It will be a very optimistic person to expect everything to work perfectly in all situations.

My setup and why. We live part time in the van, more so as the rug rags have gone off to Uni, we have no power at the van parking although it’s a big garage in the yard near the house, we only go to campsites when the boss wants a shower.

2x 12V panels in series, flexible keep it under 2m
MPPT controller
180 Ah sealed lead acid battery

Yes we live in Italy, it’s not always sunny near the alps... but under clouds we still get 1-2 amp charge for a few hours.

We only use 12V, an inverter is a good way to kill a battery.

Why a lead acid battery? There are batteries and there’s batteries as in all things, I don’t consider the cost of AGM or GEL battery is justified, we have a Bosch T5 battery a high quality truck battery designed for abuse and high cycle use ie tail-lifts, only discharge down to 12.4V and it will last a very long time.

If you have late T4 Cali only a stupid long truck size battery fits a 140 Ah, Bosch is the only supplier I have found who can supply 180 Ah of same dimensions.

I didn’t mention cost, this is what I need... can be low or high cost, Victron seem popular here but costly, I will look at Lithium at some stage as it’s double the power density ie I can get double the Ah into the same space or same Ah into half the space, I’m aware of lithium limitation as I already run a number of things off lithium.

This is not going to convince anyone either way but!.....

 

[sidepod]

So , no then. What I mean is , with UK weather I’m not convinced.

 

[AndyWT]

So , no then. What I mean is , with UK weather I’m not convinced.

Not going to argue with you, quality battery and look after it.

My son in-law has a different view, has a Halfords 45lt cool box that flattens the battery, don’t keep it charged and buys batteries

 

[sidepod]

Ok, not wishing to be a Luddite so let’s come at from a different angle.

Assuming worst case scenario and UK proof, in other words average grey/white cloud cover and not giving a second thought to which way I pitch, is the roof area on a Cali large enough to produce 5A all day every day.

Answers are single syllable/word.
YES
NO.

 

[Roger Donoghue]

So , no then. What I mean is , with UK weather I’m not convinced.

To be honest, I don't think anyone is going to convince you.

You have approached this with, in your own words, " firmly on the side of “no point”" as an opener - which means you are not open to suggestion, however, I posted above detailing exactly how it works, in the UK, and you are still "not convinced". So I'm not sure what you are after.

If you can camp for 4 days with no charging, then I agree, there is no point, for you.

A lot of people can't make 4 days with no charging, so the point suddenly becomes clear.

 

[Roger Donoghue]

Ok, not wishing to be a Luddite so let’s come at from a different angle.

Assuming worst case scenario and UK proof, in other words average grey/white cloud cover and not giving a second thought to which way I pitch, is the roof area on a Cali large enough to produce 5A all day every day.

Answers are single syllable/word.
YES
NO.

Are you looking for help, or an argument? because it feels like the latter.

You know the answer is "NO" perfectly well. Solar would be magic if it was constant through all weather, in all orientations. 25 words at least, plus a lot more syllables.

 

[sidepod]

Not looking for an argument at all, if that suits you then fine.
Simply trying understand if it’s possible to install a decent system that functions fully.
The answer as you’ve stated is no.
It’s a bit like fuel economy figures. They are meaningless.

 

[kp64zl]

Ok, not wishing to be a Luddite so let’s come at from a different angle.

Assuming worst case scenario and UK proof, in other words average grey/white cloud cover and not giving a second thought to which way I pitch, is the roof area on a Cali large enough to produce 5A all day every day.

Answers are single syllable/word.
YES
NO.

hi @sidepod - I have a solar set up 240w - keeps the battery topped up all year, keeping fridge going all summer , + charging gadgets inc laptop. In winter extends the life of leisure battery when camping. So it’s useful.

I hardly ever use electric hookup.

 

[kp64zl]

hi @slidepod - I have a solar set up 240w - keeps the battery topped up all year, keeping fridge going all summer , + charging gadgets inc laptop. In winter extends the life of leisure battery when camping. So it’s useful.

I hardly ever use electric hookup.

So yes it functions fully in my real world testing with my uses in the UK that includes Scotland in winter.

But does it give 5A continuously? I don’t care

So yes it functions fully in my real world testing with my uses in the UK that includes Scotland in winter.

But does it give 5A continuously? I don’t care

 

[AndyWT]

Ok, not wishing to be a Luddite so let’s come at from a different angle.

Assuming worst case scenario and UK proof, in other words average grey/white cloud cover and not giving a second thought to which way I pitch, is the roof area on a Cali large enough to produce 5A all day every day.

Answers are single syllable/word.
YES
NO.

Sorry sidepod I can't answer that...

It would be nice to put 4x 100W panels on the roof in series 48 volts, MPPT to suite, a lot of lithium to take all that power in the 5 hour optimal max solar (depending on the dedicated internal or external charger, lithium will soak up anything you throw at them and would need a BtB charger so they don't fry the alternator running at full output to charge the lithium when reduced solar), but the cost would out weigh any real benefit, unless cost is not an issue. A Honda 1000W inverter generator would be a better investment.

 

[EddieEagle]

A Honda 1000W inverter generator would be a better investment.
[/QUOTE]

Apparently a generator means no one will speak to you ever again !
Could be a good thing?
YES
NO

 

[sidepod]

A Honda 1000W inverter generator would be a better investment.

Apparently a generator means no one will speak to you ever again !
Could be a good thing?
YES
NO
[/QUOTE]
Passed that point a long time ago. Number of Fcuk’s given? Zero.

 

[Roger Donoghue]

This thread is wandering in a very weird direction.

Not looking for an argument at all, if that suits you then fine.
Simply trying understand if it’s possible to install a decent system that functions fully.
The answer as you’ve stated is no.
It’s a bit like fuel economy figures. They are meaningless.

Nope - I did not state that is is not "possible to install a decent system that functions fully". Not at all, and you can scroll up and check.

 

[AndyWT]

A Honda 1000W inverter generator would be a better investment.

Apparently a generator means no one will speak to you ever again !
Could be a good thing?
YES
NO
[/QUOTE]
I hadn’t thought of that, good point, I better get a geni

My comment on getting a geni was not so stupid, a small Honda inverter generator is very quiet idling away, it ramps up depending on load, it’s no good on a cramped campsite but in many instances it’s possible to site it somewhere out of the way certainly in Europe. I could find it useful but already I can’t find anywhere to put the battery chainsaw.

 

[Sp0_0k]

A huge leisure battery will solve all the problems.
You get almost free energy sucking 20amps from alternator to charge. The engine is so big it won't influence consumption much.
I run 180 + 135 Ah removable lifepo4s right now and use them for other applications off the grid and use lighter one on electric kayak, which can do 50km on charge.
This gives us 4kilowatts total power on the road.
Just juice em up in camping once a couple weeks or at car charging point or from alternator.

Current lifepo4 cells are ~200usd and 5-6kg per kilowatt. Will outlive any solar panels for years.

When the sun is brightest for the pannels, you reasonably looking for a shade When staying under the sun might require twice power for the fridges.

 

[Nathz]

Hello,
Would solar panel(s) enable the charging of two e-bike batteries of 500W if not hooked up?
Thanks.

 

[Amarillo]

Hello,
Would solar panel(s) enable the charging of two e-bike batteries of 500W if not hooked up?
Thanks.

Roof mounted solar panels are typically 100 watts, so at max output one panel would take five hours to charge one 500w battery for one hour’s maximum power.

 

[kave]

A huge leisure battery will solve all the problems.
You get almost free energy sucking 20amps from alternator to charge. The engine is so big it won't influence consumption much.
I run 180 + 135 Ah removable lifepo4s right now and use them for other applications off the grid and use lighter one on electric kayak, which can do 50km on charge.
This gives us 4kilowatts total power on the road.
Just juice em up in camping once a couple weeks or at car charging point or from alternator.

Current lifepo4 cells are ~200usd and 5-6kg per kilowatt. Will outlive any solar panels for years.

When the sun is brightest for the pannels, you reasonably looking for a shade When staying under the sun might require twice power for the fridges.

When it comes to solar on a house roof it is clearly the other way around, solar panels are a good investment and batteries are not. Here in sweden these batteries seems to cost almost two times a 240w solar install for a 120ah battery. If this battery lasts 1000 charges it will last a couple of years. If I count corectly it can charge up three bicycle batteries of 500wh. I Would rather go with solar in this case.

Lithium-Ion batteri(LiFePO4) 12,8V/120Ah med PCM Kan serie/paralellkopplas till max.48V till båt, husbil mm.

Köp Lithium-Ion batteri(LiFePO4) 12,8V/120Ah hos batteriexpressen. Rätt batteri till Rätt pris - Snabba leveranser och fri frakt*

www.batteriexpressen.se

 

[Aidy P]

Had our first road trip in France since installing the solar panel. Didn’t use hook up at all and the fridge got a hammering as it was so hot

 

[Nathz]

Thanks for all your replies.
Well, not sure what to choose as a solution though.
Would someone have a concrete experience with E-bikes batteries charging?
I have 2 chargers, a 2A and a 6A.
Thanks again.

 

[MrRHedgehog]

Would I be correct in assuming that you're hoping to connect a solar panel to your leisure battery, then use the battery to power a 240v inverter to in turn power the E bike battery charger?

Sent from my SM-G955F using Tapatalk

 

[Amarillo]

Would I be correct in assuming that you're hoping to connect a solar panel to your leisure battery, then use the battery to power a 240v inverter to in turn power the E bike battery charger?

Sent from my SM-G955F using Tapatalk

Bicycle batteries are typically 24v to 48v DC. Rather than use an inverter to transform 12v DC to 240v AC then back to lower voltage DC to charge, use an appropriate 12v step up converter. It should work fine when either on hookup or with the engine running. I’d be concerned about leisure battery drain if no power input or on solar charge.

 

[campandfly]

Thanks for all your replies.
Well, not sure what to choose as a solution though.
Would someone have a concrete experience with E-bikes batteries charging?
I have 2 chargers, a 2A and a 6A.
Thanks again.

I have an Electric unicycle that I charge now and then. When not on hook up I have tried charging it up via the inverter socket but it trips out after a very short time.
Having solar or not does not really help with my set up for charging ebikes.
I am sure some kind of charging gadget is available or can be made to charge ebikes at a slower rate but this may take quite a lot from your leisure batteries. Maybe a small portable generator could be another option.

So if I am desperate I sometimes go to a pub or cafe and ask if I may plug in while eating or drinking, offer to pay or put money in one of their charity boxes. Talk to people when camping I find most people are very helpful and will find a way to help. We also do the same if people come to us for help.

 

[Nathz]

Thanks.
I wanted to know if I could charge both batteries from the van electrical facility while camping off camp grounds.
Does not seem to be that easy and straightforward...