Merged LiFeYPO4 1000Ah Winston prismatic cells and all electric galley...

[s/v Jedi]

Originally Posted by Care2go

As we are preparing to move aboard our boat, this has been excellent to follow and read. Thank you CNB for a well documented system and breakdowns. Much appreciated.

I plan to convert our FP 44 similar to yours except we don’t have a generator on board. I intend to offset that with enough solar and battery bank to not be concerned.

Thanks again

A battery bank only stores energy: it does not generate it. Without an ICE you will need to generate every needed kWh from solar and wind. The battery bank is just to overcome the period that there is no energy production, like the solar array idle at night.

[Care2go]

Originally Posted by s/v Jedi

A battery bank only stores energy: it does not generate it. Without an ICE you will need to generate every needed kWh from solar and wind. The battery bank is just to overcome the period that there is no energy production, like the solar array idle at night.

That is what CNB points out clearly. You can easily produce enough power with solar generation for a LIFEPO4 battery system. All of this can be done while have electric range, washing machine, hot water heater etc. I really believe that the “essential ICE” will continue to be replaced. Difference in agreement aside.

[s/v Jedi]

Originally Posted by Care2go

That is what CNB points out clearly. You can easily produce enough power with solar generation for a LIFEPO4 battery system. All of this can be done while have electric range, washing machine, hot water heater etc. I really believe that the “essential ICE” will continue to be replaced. Difference in agreement aside.

I mentioned this because you wrote you intend to offset lack of genset with more solar and more batteries. The “more solar” works but “more batteries” doesn’t

[newhaul]

Originally Posted by s/v Jedi

I mentioned this because you wrote you intend to offset lack of genset with more solar and more batteries. The “more solar” works but “more batteries” doesn’t

actually the more battery forage does work as long as it is adequately balanced with solar , wind, and or hydro.

[CatNewBee]

More batteries is a good thing too, it gives you resilience for some cloudy days in series or when the sails shade the panels on long passages.

[SweareDeep]

And more batteries are also a good thing for those days, at least with our pattern of cruising which for now is time constrained, when cruising inevitably involves motoring someplace. If the bank gets full too soon then effectively one is wasting free charging.

[newhaul]

Originally Posted by SweareDeep

And more batteries are also a good thing for those days, at least with our pattern of cruising which for now is time constrained, when cruising inevitably involves motoring someplace. If the bank gets full too soon then effectively one is wasting free charging.

no that point is where you start the watermaker or the rice cooker or the holding plate refer .

However if you are so time constrained then you chose the wrong type of boat.
Sailboats have no schedule.

[s/v Jedi]

Originally Posted by CatNewBee

More batteries is a good thing too, it gives you resilience for some cloudy days in series or when the sails shade the panels on long passages.

Yes, you mean for the periods that there is no power generation... like I wrote night time was just an example.

[SweareDeep]

Originally Posted by newhaul

no that point is where you start the watermaker or the rice cooker or the holding plate refer .

However if you are so time constrained then you chose the wrong type of boat.
Sailboats have no schedule.

Well, in the world in which I live I unfortunately don't have control over the wind (or too often lack thereof) and I do at times have a schedule to keep. But if as a result I have to motor say 20% of the time then I don't for a moment think I have the wrong type of boat.

In fact, in choosing my boat light air performance was a major consideration. We have SA/Disp of 25 which to most people places us towards the performance end of the cruising boat spectrum. We see plenty of people motoring when we're sailing.

I'd simply like to capture more of the possible amp hours from that 20% of the time spent motoring. Hence more battery capacity is in the works.

[Pelagic]

With AGM or Gel Batteries I calculated my battery capacity to consume about 10% in 24hrs at Anchor.
That meant I could stay in the bulk charging phase 79-80% SOC without too much stratification until we motor sailed again.

For Lithium, how would you calculate optimum battery capacity?

[arsenelupiga]

Originally Posted by Pelagic

With AGM or Gel Batteries I calculated my battery capacity to consume about 10% in 24hrs at Anchor.
That meant I could stay in the bulk charging phase 79-80% SOC without too much stratification until we motor sailed again.

For Lithium, how would you calculate optimum battery capacity?

my thinking :
we consumed 15% per 24 hrs at anchor when 480 AH GEL with 360 w solar -panels can rotate 1 axis.

Now we have 400 ah lithium. And same solar. I have disconnected charging from alternators to house bank. In nearly 2 years i had to charge via generator 2x, else only solar. Now we have energy that nearly never runs out and we have added electric outboard as well. And have decreased usage of engines as often we run to just charge.

If you have no need to add new electric consumers probably 60% of your current battery AH should do.

[newhaul]

Originally Posted by Pelagic

With AGM or Gel Batteries I calculated my battery capacity to consume about 10% in 24hrs at Anchor.
That meant I could stay in the bulk charging phase 79-80% SOC without too much stratification until we motor sailed again.

For Lithium, how would you calculate optimum battery capacity?

charging sources?
Also keep in mind that lifepo4 doesn't actually like being fully charged all the time it prefers to run between 25% and 80% .

You state you use 10% of your banks current capacity daily ? So only about 50ah?

[Pelagic]

Originally Posted by newhaul

charging sources?
Also keep in mind that lifepo4 doesn't actually like being fully charged all the time it prefers to run between 25% and 80% .

You state you use 10% of your banks current capacity daily ? So only about 50ah?

That was before I had solar, so diesel Gen was used to run 2 chargers and make R/O water daily
8 x 8D 12v AGM Bank of 260Ah each gave me 1040 Ah at 24v

Now I have 1673W solar, and bank is 100% SOC before noon, so existing bank is now too big (unless in rainy season)

As you said Lifepo4 needs to stay below full charge so should I start at 400Ah (24v) and allow for add on capacity if needed?

[newhaul]

Originally Posted by Pelagic

That was before I had solar, so diesel Gen was used to run 2 chargers and make R/O water daily
8 x 8D 12v AGM Bank of 260Ah each gave me 1040 Ah at 24v

Now I have 1673W solar, and bank is 100% SOC before noon, so existing bank is now too big (unless in rainy season)

As you said Lifepo4 needs to stay below full charge so should I start at 400Ah (24v) and allow for add on capacity if needed?

with the amount of solar you have now it would actually make sense to have around 1k of Lfp. And use the inverter to run the watermaker.

Nobody has ever said they had to much power available on their boat.

[Mixman1]

Originally Posted by CatNewBee

I have read most of this thread and haven't seen this come up yet which makes me think I am missing something...
If you are not connected to shore power, and power assist mode is on, then the first portion of AC you get will come from the master volt. The Quattro sees this as a shore power input. If the Quattro is seeing AC at its input, it will charge your batteries using that power while also powering other loads. Doesn't this create a sort of loop where the batteries are inverted to create AC to charge the batteries? In the absence of shore power or generator input, wouldn't this just slowly drain your house bank?
I am sure this isn't the case since you have had this system running successfully for a while. I just want to understand how this section functions before I start modifying my own.