fitting new solar panels

Dumb newbie question time and a continuing saga

We have an autosleeper broadway EB 2019 model with EC 700 unit and 80w solar panel. hab battery is Yuasa 100A

i want to overcome the following issues
1. having to bring home the motorhome every ten days or so to charge it up over winter - irrespective of whether EC700 is left switched on or off (a running saga - dont go there) 
2. charge up an e bike battery - bosch powerpack 400 - input 230V 50 Hz 1.5A  output 36V 4Amp
3. increase our ability to go off grid - we can do it easily for a few nights but ideally we'd like to be able to increase that to a week. 

a reputable motorhome supplier of solar panels and power systems has suggested:

a. fit an additional 175W panel up top with Victorn MPPT controller which bypasses the EC 700 completely
b. fit a B2B master
c. buy and install a 600w inverter by linking it to leisure battery. 

he argues this will help solve the issues and the B2b means we could start the engine over breakfast and top up the battery that way. In my naivety I am assuming we cant do that with our current smart charging system on the Broadway? 

we only have space onboard for one battery; limited space for the inverter as well - as Broadway owners will know the space under the sofa where battery and boiler is is cramped! 

we dont want to spend out huge amounts on lithium batteries etc. Just want to over come the issues 1 - 3 above - off grid maximum of 6 nights and increase our ability to just turn up and not need an EHU every night. Simplicity and value for money being the key. 

Is the advice given sensible, workable - will it meet our needs? 

remember I am the SEND person on this forum - so please - simplicity so that a non Technic idiot can understand and as always - thank you for your tolerance, patience and goof humour
TIA 
steve

Too little information I'm afraid.

What time of year and in what country for off grid?  How often will you move the van and how long each day will the engine be running?  How much will you discharge the bike battery before recharging and how many days will that be before charging before? What 12v appliances will you be using when the van is pitched and not on ehu?

The storage bit is easy, disconnect both batteries as you leave the van.

A bit of a simplistic answer I’m afraid but my thinking to begin with would be…
Fit as much solar as possible on the roof with a dual controller connected direct to both existing batteries.
I’m not that up to date with why a B2B rather than a dual controller but I’m happy to learn why it’s preferable 

ok - off grid bit - in UK - ability at any time of year to use just a grass pitch without hook up on a campsite for a few nights; in France, Spain, Italy - to be able to go up to six nights off grid with no hook up - at any time of year. 
Moving the van - not every day - idea is we could stay still for up to six nights without hook up or moving van if need be
running engine - he seemed to think we could do some  topping up of battery whilst running engine during breakfast time - without moving the van
discharging bike battery - normally down by around 40% after a trip - never below 50% and that would be from a full charge a day or so before
12v appliances - TV, LED lights, water pump, toilet flush, step in and out - nothing else - fridge and cooker operate on gas - we dont use microwave unless on hook up. 

He also suggested we could fit an inverter ourselves - 600w pure sine to charge e bike battery on the go i.e. when driving around; could also charge the laptop. He seemed to think that we wouldn't need to integrate this into any system - just switch it on and off as necessary and only use when driving

and now you know why I'm asking......I'm non technic and occasionally dim but even I know when it may not feel right 

I am trying to find the simplest way of not breaking the bank but solving the e bike battery problem, the charging over winter problem and just upping our ability to stay off grid for a few nights longer than we currently do - is it possible to do it without having to install another battery, change to lithium, rip out an entire system etc etc 

Sailing boats - traditional oar and sail - I'm your man - anything motorhome or electrical - fries the brains! Sadly, i have five engineers of various disciplines in my immediate family - i did not inherit a single engineering gene but I can build good wooden boats!    Thanks everyone as always for your valuable help - it is always deeply appreciated. if you ever decide to build a boat - I can then reciprocate!

On the basis that you only intend to charge the bike battery whilst running the engine, I think you have been given good suggestions for your needs/wishes and six/seven days should be no problem if you don't watch too much TV. Do turn off the Sargent solar smart charging and send all solar to the leisure battery ie existing 80w plus new 175w.

ah now then Pete, steady on - that last bit - switch off the sargant smart charging - the fitter would need to set this up so that could be done? i got the impression from him - he'd just fit the new panel and MPPT to bypass it all and then leave everything as it is he said and it will all work together - you dont think so?

Its just a menu option on the EC700, you can do that.

For battery I would look at lead carbon gel batteries as these can be taken to a lower discharge than normal lead acid , more life cycles and faster charging, as much solar panels as you can fit on the roof even if this mean removing the original 80w panel so you could fit 2 larger panels, 

you have the option of Dual regulator or battery master to trickle charge  the starter battery but make sure you use a MPPT regulator, (i favour Victron equipment and a battery master) 

If you have enough solar you would not need the Battery to Battery charger and to run your engine 

As an example last summer we had 250w of solar and 210ah of batteries connected to a Victron MPPT regulator with a battery master , we regularly did between 10/14 day on temp holiday sites with no EHU  and charged a mobility scooter battery every day and all the 12v requirements , battery was fully charged most days by dinner,

I know have 400w solar panels and a 200ah lead carbon gel battery with a 1500w invertor , my power requirements have not changed but the extra will allow use of microwave and electric kettle whilst not on EHU, I don’t have a battery 2 battery charger fitted as I don’t dream it necessary for our use

Plymouthwelshboy - you describe two different scenarios a) using the van at any time of year for just a few days with intermittent use of the engine's alternator but not necessarily maintaining the LB in a fully charged state and b) maintaining the batteries in a fully charged state whilst the van is out of use for any length of time over a UK winter without shutting down the EC700 or being on an EHU.  I suspect most forum members with a beefed up solar and EC700 shutdown the latter.  You need to hear from someone who doesn't.

Dbvwt
I’m not that up to date with why a B2B rather than a dual controller but I’m happy to learn why it’s preferable [/quote]

I would not say a B2B is preferable .its the old way used before dual controllers came on sale. with the extra cost for a daul mppt will be saved from looking after the batteries better with what is built into a mppt controller .the mppt that I fit gives a recon charge that helps the battery life. my last camper had the same battery at 10 years old and when tested still had 100% amps charged in the battery .when people let the battery run low on power shortens the life fast and end up needing to be replaced.
so a good solar charge system will save you money and have power when needed. I was parked on the north Devon coast a few weeks ago and another camper pulled in and in the morning came over and asked if I had jump leads and could help as they had no power to start .I was boiling my kettle on the electric they could not see how I had so much power after running the heating in the night. i then put my charge lead I use to charge my cars from the camper solar power to there battery and after 2 hours they had charged up and yes they had the lovely sargent electrics that's only good for the sales talk

For the OP van as is, the easy option is to completely bypass the Sargent bits altogether. A Dual battery solar controller taking the solar panel output directly to both the VB and LB's. The controller (PWM in my case) ratio can be changed, mine is 20% VB and 80% LB
Both outputs go direct to the batteries via an inline 10A fuse at each battery +ve terminal.

This ultra simple system works perfectly and we virtually never use or need an EHU, we only use one if it's cost is included in a site fee. We rarely use sites either!

I would consider using B2B to allow an inverter to be run, but only when the vehicle is being driven. The 400w charger you quote will need at least 500w from an inverter, at 14v (alternator output voltage +/_ ) that's 36Amps more or less. 
As an example your 100Ah LB discharged to 50% will allow the use of 50Amps for 1 hour. So if the inverter is used to charge the bike batteries just using the LB, you'll get one charge. But if you have 2 bikes then it'll be below 50% capacity (the minimum it should be used for for any longevity) long before both bike batteries are full.

Re running the engine to charge via B2B this I would NEVER do, the alternator will need less than 2Bhp from the engine which is therefore at idle. it is difficult to think of a worse thing to do to a modern diesel engine. They should be running at around 75% of their max power whenever possible. IMHO you should never start one unless it is just about to be driven....

Back to solar, my 130w panel keeps both of my batteries at 100% full charge 365 days per year. If being used when the van is in use (circa 9 weeks per year, rare EHU) the LB is usually full 10 to 11am next day, even in less than perfect weather. BUT there again I don't have an inverter, nor electric bikes to charge.......

the two different scenarios - all i want is to be able to go for a few days extra off grid, charge e battery and laptop whilst off grid and/or whilst engine is running and make sure that whether EC700 is switched on or off  that I dont need to bring it home every ten days which is the current issue over winter. I get the bit about switching off the EC700 but as Ive said before - it doesnt seem to make any difference - the battery is fine but it will discharge down over 10 - 14 days to point where it needs plugging in - there could well be an issue with our EC700? 

Unless I go to lithium - I cant see where we can fit a second battery in a broadway EB - certainly there isnt the room under the sofa bed where current battery is - so where do people put the other battery? 

I see what freelander is saying - do away with the battery to battery charger because 250W up top and an inverter would cover our needs? 

At the moment - I've been quoted around £2000 for the following: 

Victron Smartsolar MPPT regulator to replace your existing PWM connected to the Sargent consumer unit @ £159.95
Installation charge @ £42.00 (Estimated ½ hour)
 
Victron 175W solar panel c/w Victron Smartsolar MPPT regulator installed directly to the leisure battery (including installation) @ £749.00
 
Battery Master @ £0.00 (included with solar panel installation)
 
Sterling 70A Battery to Battery charger @ £479.99
Parts and consumables @ £120.00 (Estimated)
Installation charge @ £336.00 (Estimated 4 hours)
 
Victron Smartshunt battery monitor @ £150.00
Installation charge @ £84.00 (Estimated 1 hour)


The supplier also suggests that our plug-in 300w inverter into the cab 12v cig socket would charge the e bike battery whilst the engine is running with no problem  and there'd be no need for a bigger inverter. 


I never thought I'd hear myself say this but....sssh......building complex wooden boats is so much easier........  than trying to work out the simple electrics on a motorhome - guess its the way my brain is wired - yes great pun - anyway, thank you all as always for your good humour and exceptional patience

ian thanks - that helps clarify what other patient souls are saying I think - 

I understand what the supplier is saying and they are very reputable and stuff we've had done with them has been fantastic. I'm just still slightly hesitant about the costs and also about the B2b bit - its stretching my poor brain.......

On my phone typing this so will reply again when ipad charged. The 70amp Sargent B2B charger is overkill and way to large for a single lead acid battery

thanks chris - i think thats one of the bits I'm still stumbling over along with the point made about running a diesel engine at idle being bad for engine - that bit was troubling me as well.

ok - if im getting this right
switch off EC700 when in storage - and 175w panel and 80w panel should keep both batteries topped up even over winter

bypass the sargant unit completely - being proposed for the new panel - but also do it for the existing 80w panel - connect both to MPPT controller

(we only have one 100a battery on board)

install a 600w inverter for the e bike - to be switched on only when on journeys between places  - but have a battery2 battery charger installed but for one battery 70am B2b is overkill

How am I doing? its hard work this motorhoming electrical malarkey  - i sooo much prefer working with wood 

Nearly!!

The B2B will only charge the LB when it needs to be charged, so, if LB is full B2B will give zero to it.

If, however, you then switch on the 600w inverter, the B2B will see the load and power the LB accordingly (I THINK!) Others, particularly Chris Freelander will comment/correct as req'd I'm sure

Not even sure you need the extra 175W panel, previous vans with the above quoted exact system had only 100w ones with zero issues. With the B2B you will always meet your bike needs and keep the LB full. All  the solar has to do is meet your engine off loads, and 80w will do that and keep both batts full all yr round.....

Plymouthwelshboy wrote:ok - if im getting this right
switch off EC700 when in storage - and 175w panel and 80w panel should keep both batteries topped up even over winter

.....

As I have said before, if you shutdown your EC700 your existing solar should keep your VB fully charged in the winter and your LB will be fine without charge for up to 3 months if its in good nick and was fully charged to start with.  If as you report your VB is going flat after 14 days with the EC700 shutdown, you have a fault.  Before you spend any money upgrading your system you need to have this fault put right.

With regards to the B2B charger, The Charging output for a lead acid battery (ie Amp output) should generally be 10% - 20% of the battery's maximum capacity. For example, a 100Ah Lead acid battery would require a charger rated at between 10amp - 20amp. so a 70amp B2B charger is overkill and a 30amp B2B would be a better suited and a lot cheaper, this 30amp gives you the option of upgrading the Size of your battery bank.

The other thing to consider is to replace the original fitted cables from solar panel to regulator with the correct size , the ones that was fitted in my van and from the Sargent regulator to panel and control board where way undersized


In all honesty I would not even do this as I don’t think you will gain much for the added expense 

Victron Smartsolar MPPT regulator to replace your existing PWM connected to the Sargent consumer unit @ £159.95
Installation charge @ £42.00 (Estimated ½ hour)


If you use your 300w inverter to charge the bike battery I would install a separate cig lighter socket with heavier duty cable near to the Hab battery 

Plymouthwelshboy wrote:....
b. fit a B2B master
....
he argues this will help solve the issues and the B2b means we could start the engine over breakfast and top up the battery that way.
...

This seems poor advice.  Not only is is bad for the engine, its bad for the planet, its bad for your neighbours and its bad for your pocket as you are paying for the diesel.  If all you need to do is top up the LB, your solar should be able to do this on its own.  If you need to do more than top up your LB, your engine will have to run for much longer than it takes you to have breakfast.  If you fit a B2B it needs to charge the VB from the LB rather than the other way around but if you fit a dual battery solar regulator there should be no need for it.

One comment, really quite unrelated to the OP problem, shows, for me, at least the mine of information that the OP has received for his "problem"

Differing views, of course, but all pointing to a solution to his problem

That's why I like this forum so much, and am happy to be part of it.

Just a thought..

Chris, apart from the b2b charger bit,which is the other bit you wouldn't bother to do...I'm slightly confused, which is easy to do where I'm concerned....would you not do any of it, or not fit the extra solar, or just fit the victron MPPT controller...sorry to be so dim...

I guess the supplier has identified that your newer van has a smart alternator and will therefore benefit greatly replacing the split charge system with a B2B especially when charging the bike battery on the move.

I've managed ok with 80w solar for many years but had 200Ah battery and there is not room in the Broadway EB for mor than one battery.

Larger conductors will increase the efficiency of the solar system but the improvement is so marginal that its not worth the effort.

Increase your solar panels from 80W to 255W as proposed but put all the output through one dual battery MPPT solar regulator that bypasses the EC700 and replaces the existing regulator and don't bother with the B2B.  Depending on the time of year, weather and where you're parked, this may be enough to allow an inverter to charge your e-bike and/or laptop.  It may also be enough to leave the EC700 on whilst the van is out of use but I have no idea why you would want to do this as all it will be doing is wearing out your LB.

Thanks everyone. I think some further conversation to be had with the supplier. Deeply appreciate all your advice thank you everyone