Sanity Check: Solar Charging Upgrade

[jms28]

Hi,

I currently have 2 x Solara SM 225 M (68W each, I think) connected to a Votronic MPP 350 Duo Digital to charge two seperate battery banks (starter & house) in my motor boat. Rather small sized, I know :/

Hence, I recently purchased 2 x Jackery SolarSaga 100W foldable solar panels to start the upgrading process. I now know that I should not mix these 2 strings connected to one single solar charger. So my plan is to buy an additional Victron MPPT charger for the 2 Jackery panels and then to run both strings seperately:

• String 1: Solara + Votronic --> Starter + House Battery Bank (the latter especially for storage to keep batteries at healthy levels)
• String 2: Jackery + Victron --> House Battery Bank only (the larger consumer, especially when anchoring)

Questions:

1. Would you agree with this plan overall? Anything I forgot to consider?
2. The Solara panels are quite old and will need to be replaced relatively soon. But even if I were to get identical Jackery panels, would the Victron solar charger even be able to charge 2 seperate battery banks? All Victron solar chargers only come with one output terminal which makes charging two separate banks rather tricky, especially if these are comprised of different battery types. So I am well advised to run seperate solar chargers anyway, correct?
3. Both battery banks are being charged by the same Victron IP22 landline charger (has 2 seperate output terminals). Can I track both solar charging and landline charging in the same app and/ or does it make sense to add an additonal Victron "smart" device for the overall power monitoring? Asking as both the Solara panels and the Votronic charger are rather old. So I'm already planning for the day that these two will need replacement as well and I'm keen to learn more about the wider Victron ecosystem and what might makes sense for me to consider.

Thanks in advance,

Mike

 

[PaulRainbow]

Hi,

I currently have 2 x Solara SM 225 M (68W each, I think) connected to a Votronic MPP 350 Duo Digital to charge two seperate battery banks (starter & house) in my motor boat. Rather small sized, I know :/

Hence, I recently purchased 2 x Jackery SolarSaga 100W foldable solar panels to start the upgrading process. I now know that I should not mix these 2 strings connected to one single solar charger. So my plan is to buy an additional Victron MPPT charger for the 2 Jackery panels and then to run both strings seperately:

• String 1: Solara + Votronic --> Starter + House Battery Bank (the latter especially for storage to keep batteries at healthy levels)
• String 2: Jackery + Victron --> House Battery Bank only (the larger consumer, especially when anchoring)

Questions:

1. Would you agree with this plan overall? Anything I forgot to consider?

That's fine.

2. The Solara panels are quite old and will need to be replaced relatively soon. But even if I were to get identical Jackery panels, would the Victron solar charger even be able to charge 2 seperate battery banks? All Victron solar chargers only come with one output terminal which makes charging two separate banks rather tricky, especially if these are comprised of different battery types. So I am well advised to run seperate solar chargers anyway, correct?

As the engine battery will normally be charged, you will be wasting almost all of the possible yield from the panels connected to the engine battery. Any reason not to fit a VSR ?

Would help to know your battery types and how the batteries are charged by the alternator/s.

3. Both battery banks are being charged by the same Victron IP22 landline charger (has 2 seperate output terminals). Can I track both solar charging and landline charging in the same app and/ or does it make sense to add an additonal Victron "smart" device for the overall power monitoring?

A Victron Smart Shunt would be a good choice.

Asking as both the Solara panels and the Votronic charger are rather old. So I'm already planning for the day that these two will need replacement as well and I'm keen to learn more about the wider Victron ecosystem and what might makes sense for me to consider.
Thanks in advance,

Mike

 

[Sandy]

I currently have 2 x Solara SM 225 M (68W each, I think) connected to a Votronic MPP 350 Duo Digital to charge two seperate battery banks (starter & house) in my motor boat. Rather small sized, I know :/

As you have a motor boat I'm wondering why you have a solar panel charging both the engine and house batteries?

Is it just to keep the battery fully charged when you are not using the boat or do you spend days at anchor and consume a lot of power?

I sail with 200 watts of solar panels that keep up with multi-day summer passages.

 

[Neeves]

I sail with 200 watts of solar panels that keep up with multi-day summer passages.

What does that mean? Your 200 watts of solar runs the autopilot, instruments (chart plotter), lights (not so critical in Scotland mid summer), engine start, windlass, fridge (and a full electric galley )

Jonathan

 

[Sandy]

What does that mean? Your 200 watts of solar runs the autopilot, instruments (chart plotter), lights (not so critical in Scotland mid summer), engine start, windlass, fridge (and a full electric galley )

Jonathan

In a word yes.

But there is a bit of nuance. I don't run a fridge, but load it with frozen stuff. I use gas and a Mr D slow cooker to cook on passage. The starter battery is separate from the house and I always run the engine when using the windlass. Old fashioned I know, now I have a proper anchor. A Knox if anybody is interested.

Next you will be suggesting an electric blanket for northern latitude sailing!

 

[PaulRainbow]

In a word yes.

But there is a bit of nuance. I don't run a fridge, but load it with frozen stuff. I use gas and a Mr D slow cooker to cook on passage. The starter battery is separate from the house and I always run the engine when using the windlass. Old fashioned I know, now I have a proper anchor. A Knox if anybody is interested.

Next you will be suggesting an electric blanket for northern latitude sailing!

Just about to dish up a beef pot roast from Mr D, excellent bit of kit. I guess it appeals to your Scottish sense of "money saving". Does mine, and i'm not Scottish.

 

[Sandy]

Just about to dish up a beef pot roast from Mr D, excellent bit of kit. I guess it appeals to your Scottish sense of "money saving". Does mine, and i'm not Scottish.

A cracking bit of kit. You will always get a good size dram onboard!

 

[jms28]

Thanks for the replies and apologies for my belated response!

That's fine.

As the engine battery will normally be charged, you will be wasting almost all of the possible yield from the panels connected to the engine battery. Any reason not to fit a VSR ?

Would help to know your battery types and how the batteries are charged by the alternator/s.

A Victron Smart Shunt would be a good choice.

You mean I would be well advised to connect both solar charging arrays to the house battery bank only as the starter batteries will be charged by the alternators anyway, correct?

I had a BlueSea VSR but removed it last season as I was suspecting it to be the cause for a discharge on the starter battery side. However, I think I will refit it again this summer as I've come to the conclusion that the starter and house banks must be connected elsewhere. Here also lies the reason for wanting to charge the starter bank with solar btw: for years, I've been struggling with slowly discharging starting batteries while at anchor. I need to get to the bottom of this finally...

Batteries are AGM, no lithium planned anytime soon.

Re the Smart Shunt: I've come across the Victron Lynx DC Distribution System. Any experience with the entire system comprised of Power In, Shunt and Distributor? The shunt has a Bluetooth connection and no additional screen for readings is mandatory, correct?

As you have a motor boat I'm wondering why you have a solar panel charging both the engine and house batteries?

Is it just to keep the battery fully charged when you are not using the boat or do you spend days at anchor and consume a lot of power?

I sail with 200 watts of solar panels that keep up with multi-day summer passages.

And yes, the other reason for charging both banks is that exactly: to keep the batteries minimum charged over the entire year.

Said Votronic MPP 350 Duo Digital solar charger has the second output for that reason exactly I think. So no harm in connecting that to the starter battery bank, while connecting both the main output from the Votronic + a separate Victron charger w the Jackeries to the house battery bank, right?

Thank you!