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

[Catapault]

Originally Posted by CatNewBee

Don't forget the ice maker 4 the mojitos and frozen margharitas...

My watermaker runs on both, 220v and 12v. With the LFP and 5kVA inverter I do not see any problem to run it on any of the 2 sources, (yelds 80...100 l/h) when the bank is full. It will not suck up 15kWh that are stored in the battery. I would rather top up the water daily for an hour or so instead of emptying the 600l during the week and then refilling for 6-8h.

This also helps to not keep the LFP at full SOC for long, they like to be heavy used and cycled.

We now run the icemaker all day, most days. It dosn't use much power. (Desktop unit).

Also turn on the water heater at 2-3 pm is (it just went on), off the solar.
I've got a smaller . 60L/hr 220/12v watermaker, runs just fine all day off the Solar when it is 'make me water' day.

Genset comes on sometimes when we are doing something that needs lot of power, such as the Air-fryer, and its already evening, or baking. Genset is pretty quiet so not a big deal.

I expect many of these to be much better when I eventually get Lithium in the battery bank. But even without, the Genset goes on FAR less frequently then it did before.

Regards

Mark.

[CatNewBee]

Originally Posted by arsenelupiga

thanks for posting that stuff. really informative.

What would be different if your solar capacity would be 1/2 of what you have now, everything else the same ?

Well, with half the Solar, I guess, I would have on sunny days the energy I use recharged, without extras for the watermaker or cruising electronics, but on anchor it would be OK, maybe I would not make hot water daily too, that would safe 150..160Ah and prolongue the time to recharge.

Well, any cloudy day would not be compensated by solar, after 2 or 3 days with clouds I would probably have to run the generator for 2-3 hours to recharge (i can charge with 300A from 220V sources by the quattro - 220A and the 2 Cristec - 40A each, plus the solar up to 100A).

So it would not kill me, but I would have to burn diesel.

With that setup now I am completely independent on other sources and have on good days excess energy for the water maker or washing machine or other stuff.

[CatNewBee]

Originally Posted by Catapault

We now run the icemaker all day, most days. It dosn't use much power. (Desktop unit).

Also turn on the water heater at 2-3 pm is (it just went on), off the solar.
I've got a smaller . 60L/hr 220/12v watermaker, runs just fine all day off the Solar when it is 'make me water' day.

Genset comes on sometimes when we are doing something that needs lot of power, such as the Air-fryer, and its already evening, or baking. Genset is pretty quiet so not a big deal.

I expect many of these to be much better when I eventually get Lithium in the battery bank. But even without, the Genset goes on FAR less frequently then it did before.

Regards

Mark.

That will be my next gadget - an ice maker for the sundowners... [emoji108]

[LilleVenn]

Hello CNB
nice setup, and y very much like the way you are dealing with your diesel consuption
Unfortunately I don't have your knowlege about electronics, but my simple LiFePo test system is running in the cellar.
Later this year we should get our Cat and there I would like to install a similar system like you have (5 * 360W with MPPT Charger and 1200AH LiFePo)
For sure I can profit from all your information here.
Thank you for that

[CatNewBee]

Sure, you're welcome to ask questions if you not find the desired informatin in the thread.
So have fun planning !

[CatNewBee]

Today some more news about LFP and Quattro installation.

In the marina there are only 6A shore power outlets. Using the Solar and the LFP with my installation changes I easily can use my Airconditioners, by using the power assist function of the Victron without blowing the breakers at the pontone.

Also full use of the galley gear on 6A shore power is no problem anymore.

Like my setup.

[john61ct]

With only mains input, how many hours can the aircon run at a time before you need to stop and recharge?

[CatNewBee]

Have not tested yet. Will do next weekend...

I assume running A/C during the night where solar input is zero?

How many of the 4 units shall run? I woud - if necessary - only run the master bedroom for few hours before going to sleep, maybe the salon too. Usually during the day you are outside in the cockpit, great shade from the panels, and light wind makes it pleasant.

[john61ct]

I think start with just one, the smallest. I assume aircon's wired through the inverter's output, not directly off shore?

And yes, no solar, just buffering the crippled mains.

Startup surge is the big draw wattage, average AH per hour will vary.

With a small space and good insulation, the answer may well be, all night.

[CatNewBee]

I will check it out and post.

[CatNewBee]

So some results. Shore power limited at 6A, power assist on, one AC in the salon draws 8A extra from the battery with no solar. So 200Ah per day rough estimation for A/C and shore power 6A.

With solar during daytime no power from the battery, solar controller set on float 13.4V, it supplies then the A/C, the fridges etc. and charges if necessary.

That said, on sunny weather 1 A/C can potentially run for ever on shore power 6A without draining the battery.

[john61ct]

Thanks, interesting, lots of juice!

Best IMO to just stick to watts units for the shore power, then use AH for 12V DC only to avoid confusion.

The extrapolation from max power drawn while the compressor's on during the initial room cooldown process, to AH used over X amount of time won't be accurate just using math.

Which currently we'd get ballpark of 140AH per hour draw, reduced by 60AH by the crippled mains, leaving 80AH per hour carried by the bank.

But that should be a fair bit less IRL after the first hour or two, assuming the room's pretty sealed, the thermostat will periodically shut down the max output rate, crudely put cycling Y% of each hour. How much depending on the temp differential between thermostat setpoint and outside ambient and how well the space is sealed & insulated.

Plus inverter losses play a role in the other direction.

Looks impractical to actually test, measure AH drawn for more than a few hours, six hours might fully drain nearly 500AH from the bank.

[CatNewBee]

Will check that on battery only at some point.

At the moment it is just running full, set to 22°C, outside 30°C, cabin temp approx. 24°C, so I assume that is the max power it draws. It translates to approx. 1.5kW.

Battery capacity is around 15kWh, so good for 10h until empty. ( if nothing else is on )

[CatNewBee]

Sorry, I have to correct myself. Used the Victron interface to check the Inverter for more accurate readings on the loads.

The A/C use only 1020W under load and switch off when Temp reached, so longer usage time with the battery expected. Also power assist has a strange behaviour near 1000...1200W, it does then draw just 2..3A on AC only for a long time and uses 50A from the Battery to assist, if you switch on the second A/C unit (2000W total), the input current on AC goes to 5.9A, and the battery DC current remains around 50..60A. so there is a risk of unnecessary discharging.

When the A/C reaches target temp, it switches off, the victron then slowly goes to bulk and increases the charge current to 90A, what corresponds to 5.9A on AC input. Pretty quick re-charge.

Will do the DC tests later.

[john61ct]

Yep, what I meant by "cycling", some units manage variable compressor spped too, not just on / off.

That's why those dreaming of off-grid aircon powered by solar need to get the space super-insulated first.

Sound like the Power Assist works, if not optimally, at least pretty well.

Ideal for high startup-surge consumers, makes things work even with a bit underpowered genny / mains source, don't have to supersize the genny carried.