Portable solar and / or B2B (1 Viewer)

Mar 14, 2020
636
501
Isle of Man
Funster No
69,394
MH
Autotrail Cheyenne
Exp
Since 2015, still learning
After reading some posts by Richard and Ann and AdamB I am seriously considering portable solar to recharge our needs when wild.

Just wondering where the mppt goes? On the panel or near batteries? I fancy one of those bluetooth ones!
Are there any recommended brands / kits?

I have an 03 Cheyenne with easy access to the leisure batteries in the rear. Would approx 6 m be too far to run a battery to battery charge system or does that go via the Sargent?

Thanks, in anticipation
Cush
 
Dec 2, 2019
3,555
7,699
Amersham
Funster No
67,145
MH
van conversion
Exp
Since 2019
Controller should be as close as possible to the battery.
 
Mar 23, 2012
9,451
31,634
sleights
Funster No
20,245
MH
c class
Exp
1
Why portable solar do you mean a fold up panel?. I would fit one on the roof over where the battery is and the solar controller next to the battery.

Subscribers  do not see these advertisements

 
OP
OP
Cush
Mar 14, 2020
636
501
Isle of Man
Funster No
69,394
MH
Autotrail Cheyenne
Exp
Since 2015, still learning
Why portable solar do you mean a fold up panel?. I would fit one on the roof over where the battery is and the solar controller next to the battery.

Sorry, yes, fold up. I will have another use for it when not being used in the van so foldable will kill 2 birds etc etc. I also understand that as it is angled when set up it doesn't need to be as physically large as roof mounted ones. A Bluetooth mppt would let me monitor it like the fixed systems do. I think.

Thanks to both of you for advice re the controller.
 
Jul 12, 2013
3,853
5,229
The City of Henlow
Funster No
26,906
MH
Adria Supreme
Exp
Since 1980
Although you may have dual use for the folding panels, the inconvenience of setting up each time you stop, with trailing wires, to say nothing about it getting 'borrowed' by others when you are not in attendance.
 
OP
OP
Cush
Mar 14, 2020
636
501
Isle of Man
Funster No
69,394
MH
Autotrail Cheyenne
Exp
Since 2015, still learning
Although you may have dual use for the folding panels, the inconvenience of setting up each time you stop, with trailing wires, to say nothing about it getting 'borrowed' by others when you are not in attendance.

thanks for the words of advice. The plan would be, if the controller has got to be close to the control unit then I'd mount this permanently in the rear locker and have a quick release plug between the controller and panel, probably close to the controller. I could always climb the ladder and put it on the roof out of the way or only have the panels out when were in. I don't mind the faffing around, I quite like it.

Appreciate you making me think about security. Thanks again

Subscribers  do not see these advertisements

 

TerryL

LIFE MEMBER
Mar 5, 2010
6,154
8,144
North East
Funster No
10,511
MH
Low Profile
Exp
2009
To answer the thread title if you tend to stay put in one place then solar. But if you move around then a B2B will recharge your batteries in an hour's driving. Personally I've got both, plus 2 leisure batteries and a battery master which keeps engine battery topped up if we don't move for a bit. Never have to think about it now.

NB don't use the B2B to recharge by just running the engine at a standstill - not good for the motor.
 
Oct 12, 2009
10,438
23,286
SW London, Poland and all Europe
Funster No
8,876
MH
A Class N+B Arto 69GL
Exp
Since 2009
I agree with TerryL's comment about B2B.

As regards angling solar panels vertically, that is only efficient if you also are around to follow the sun horizontally. I have seen studies that show that flat panels which receive the rays from whichever direction the sun is horizontally are as efficient as vertically angled panels fixed facing south which will receive nothing at sunrise and sunset, wheras a flat panel will receive some, albeit reduced, input.

Geoff
 
OP
OP
Cush
Mar 14, 2020
636
501
Isle of Man
Funster No
69,394
MH
Autotrail Cheyenne
Exp
Since 2015, still learning
Hi TerryL and nicholsong
Thanks for your guidance and experience. It's much appreciated.

Take care

Subscribers  do not see these advertisements

 
OP
OP
Cush
Mar 14, 2020
636
501
Isle of Man
Funster No
69,394
MH
Autotrail Cheyenne
Exp
Since 2015, still learning
For anyone interested in the effect of tilt, or lack of it. Thanks Nicholsong for the pointer.
Most issues with being flat are that they get dirtier quicker, although not such a problem with a temporary set up or easily accessed one


It's just one source but other sites seem to pretty much agree. Tilt makes less than 10% improvement. Facing due south is the most important thing. Curious as to how you get a panel with 0 tilt (flat) to "face" any direction 🤔
 
Jan 19, 2014
9,322
24,581
Derbyshire
Funster No
29,757
MH
Elddis Accordo 105
Exp
since 2014
Our panel output more than doubles when tilted, It depends what time of year though, massive difference in October - 2 amps flat shoots up to 8+ amps at 40° tilt South.

Edit: Just looked up the photo album. 9.2 amps on the 28th October from our150w panel tilted 👌
Screenshot_20200608-211250_Gallery.jpg
 
Last edited:
Dec 2, 2019
3,555
7,699
Amersham
Funster No
67,145
MH
van conversion
Exp
Since 2019
Also, the latitude you are at that moment, makes a big difference. That graph looks at a very low latitude, you will never gonna get that, at 50 deg plus north latitude.

Subscribers  do not see these advertisements

 

Lenny HB

LIFE MEMBER
Oct 18, 2007
52,704
147,664
On the coast in West Sussex
Funster No
658
MH
Hymer B678 DL
Exp
Since 2008 & many years tugging
No problem with fitting a B2B with the batteries 6m you just have to make sure you use large enough cables to keep the volt drop to a minimum.
 
Mar 30, 2019
1,089
1,380
East Sussex
Funster No
59,486
MH
Trigano Tribute
Exp
Since 2017
From about April to September it doesn’t really make much difference whether your panel is flat or tilted, as the sun is higher in the sky. My batteries are pretty much recharged by 10am (255 watt panel mppt Votronic charger) during this period. Generally we find our power usage drops during the summer as we’re outside more.
Outside these months it does improve the output of solar if you match the angle to the average sun angle on the day.
I use an iOS app called simply solar, it gives the best angle and where to point your panel.
 
Jan 7, 2017
30
25
Lincolnshire
Funster No
46,786
MH
Autotrail Vintage
Exp
Newbie
To try and answer a couple of your other questions -

The MPPT is better closer to the battery, than the panel. My understanding is that there is normally a higher voltage and lower current on the run from the panel to MPPT, than from MPPT to battery, and therefore any loss of current due to resistance will be less.

For your quick disconnect, you could probably use MC4 connectors, the standard connector used in Solar setups. They are cheap enough, easy to fit and crimp yourself, and pretty easy to disconnect especially if you have the little tool.

Subscribers  do not see these advertisements

 

DBK

LIFE MEMBER
Jan 9, 2013
17,969
47,804
Plympton, Devon
Funster No
24,219
MH
PVC, Murvi Morocco
Exp
2013
Your MH has lots of roof space so I think you will find for the price of a folding panel you could get twice or even three times the capacity with fixed panels on the roof. Fit and forget, they will just work and when it's cloudy a flat panel will gather more power than one pointed to the invisible sun.

If you need a portable panel for another use then buy a second one, whatever is best, for that specific application. 😀
 
OP
OP
Cush
Mar 14, 2020
636
501
Isle of Man
Funster No
69,394
MH
Autotrail Cheyenne
Exp
Since 2015, still learning
Also, the latitude you are at that moment, makes a big difference. That graph looks at a very low latitude, you will never gonna get that, at 50 deg plus north latitude.


I thought the figures were % of the max possible at that time? The tables is from the energy saving trust and for our latitudes.

Thanks for all of the input. I'll keep doing the research. Battery to battery is gaining momentum and the solar a close second. Didn't quite understand the b2b in the earlier. Price will win out.

Thanks again to All
 
Apr 27, 2016
6,802
7,843
Manchester
Funster No
42,762
MH
A class Hymer
Exp
Since the 80s
Look at the panels of a solar farm next time you see one. They are tilted. If it was even marginally better to lay them flat, that's what they'd all do.
 
Dec 2, 2019
3,555
7,699
Amersham
Funster No
67,145
MH
van conversion
Exp
Since 2019
Indeed. And the angle of incidence, is directly related to the latitude of that location. Or a median for the summer and winter angle, which results in a spring autumn ideal angle. As DBK mentioned, in cloudy weather, best is flat facing the sky. We all fit our panels flat and as much as possible. PV is cheap, with under 200 quid, you could get 500-600w of solar if you know where to shop.

Subscribers  do not see these advertisements

 
OP
OP
Cush
Mar 14, 2020
636
501
Isle of Man
Funster No
69,394
MH
Autotrail Cheyenne
Exp
Since 2015, still learning
Any thoughts on this?
I'm a complete autosparks novice and trying to educate myself 🤓
 

Attachments

  • dc_chargers_and_the_alternatives_-_vehicle_charging.pdf
    85.8 KB · Views: 24

ManTheVan

LIFE MEMBER
Jan 11, 2020
1,447
2,747
South Devon, UK
Funster No
67,952
MH
Rapido C class
Exp
Yottie convert
Indeed. And the angle of incidence, is directly related to the latitude of that location. Or a median for the summer and winter angle, which results in a spring autumn ideal angle. As DBK mentioned, in cloudy weather, best is flat facing the sky. We all fit our panels flat and as much as possible. PV is cheap, with under 200 quid, you could get 500-600w of solar if you know where to shop.

Can you suggest where that shop might be? Haven’t seen anything remotely close to that amount of capacity for that sort of price, but would love to investigate!
 
Dec 2, 2019
3,555
7,699
Amersham
Funster No
67,145
MH
van conversion
Exp
Since 2019
Triplesolar ebay shop, 285w for 80 quid. Lots in stock.
CCLComponents, based in Scotland, with nationwide delivery; trina 275w for 90 quid, or 340w for120.
Wind &Sun good deals on inverters, various components and batteries.

Subscribers  do not see these advertisements

 
Apr 27, 2016
6,802
7,843
Manchester
Funster No
42,762
MH
A class Hymer
Exp
Since the 80s
Any thoughts on this?
I'm a complete autosparks novice and trying to educate myself 🤓
I have the greatest respect for these guys, and if I was going on an expedition into the Australian outback I would listen very carefully to their advice. However kitting out a motorhome in Europe throws up different priorities.

First, a translation of Oz slang into MHFun slang:
continuous solenoid = split charge relay
voltage sensitive solenoid = voltage sensitive relay
thumper = leisure battery/habitation battery
DC-to-DC charger = battery-to-battery charger (B2B)

The issue of 'load-sensitive alternators' has largely disappeared from modern vehicles, but has been replaced by the 'smart alternator' issue which causes similar problems. I'd say all alternators that are not 'smart' are the load-sensitive type.

He is right in that a simple split charge relay is fine for many, and will charge a leisure battery reasonably well, especially if it's a similar type to the lead-acid starter battery. However if you have a big leisure battery bank, or different types like Gel or Lithium, the alternator doesn't really do a good job.

B2B chargers have come a long way from the kind he is describing. They are much more efficient, and can boost voltage and current to supply exactly what the leisure battery requires. Most are settable to the battery type, and do multi-stage intelligent charging for a full charge without overcharging.

Voltage-sensitive relays are fine in simple systems where the only reason the starter battery voltage rises is the alternator when the engine is running. More complicated systems with solar and mains hookup charging will charge the starter battery too, and then a VSR will become a liability.

If you have plenty of solar power and the weather is good, you might not need a B2B. But as the days get shorter you need something more, and a B2B can fill up the batteries with a much shorter drive time than a split charge relay can.
 
OP
OP
Cush
Mar 14, 2020
636
501
Isle of Man
Funster No
69,394
MH
Autotrail Cheyenne
Exp
Since 2015, still learning
Thank you so much autorouter I'm sure I won't be the only one that will be wanting to thank you for that info. 😇🧐
 
OP
OP
Cush
Mar 14, 2020
636
501
Isle of Man
Funster No
69,394
MH
Autotrail Cheyenne
Exp
Since 2015, still learning
So ....
Sat in the van in one of our favourite spots overlooking the bay. Got a reply from the good people at Sargent who told me that
"The PSU 2007 does come with a built in split charge relay which links your leisure battery to the vehicle one so while you are driving the van the two batteries will be charged up by the alternator of the vehicle."

How did I never notice. Anyway, before I set off the LB read 12.8 on the panel (not been on EHU before setting off). At the end of a 40 minute B road journey it read 13.3.

Guessing no need for a bat 2 bat now?

Happy to be schooled on the tech side ( autorouter )

Currently pondering why the ultrashort won't do the right thing and yes, the cover is off and bass is on and it is full of water. 😖
When you buy a lemon 🍋 buy gin too ( van isn't really a lemon incase the seller is reading 🙋)

Cush

Subscribers  do not see these advertisements

 
OP
OP
Cush
Mar 14, 2020
636
501
Isle of Man
Funster No
69,394
MH
Autotrail Cheyenne
Exp
Since 2015, still learning
Edit of the above. Must wear glasses and proof read

Ultrastore not ultrashort and gas not bass
😔
 
OP
OP
Cush
Mar 14, 2020
636
501
Isle of Man
Funster No
69,394
MH
Autotrail Cheyenne
Exp
Since 2015, still learning
Currently pondering why the ultrashort won't do the right thing and yes, the cover is off and bass is on and it is full of water. 😖

Appears sorted now. Think before t was wind direction and strength 😧

Subscribers  do not see these advertisements

 

Join us or log in to post a reply.

To join in you must be a member of MotorhomeFun

Join MotorhomeFun

Join us, it quick and easy!

Log in

Already a member? Log in here.

Latest journal entries

Funsters who are viewing this thread

Back
Top