AGM or Wet Cell

[a64pilot]

Originally Posted by sailorboy1

I'm not going to argue the fine points. The bottom line if your 1000w of solar can not get your battery charged it has an issue. I know what fully charged is and have been doing this longer than you have been repeating crap you read on the internet.

How long ago did you replace your bank?
To a great extent I give you credit for pointing out why obsess over your bank, buy an inexpensive one, treat it OK, consider it a consumable and replace it when it dies, don't obsess over it.
I'd say you don't know what fully charged is, yes Solar can bring a bank up to full with boat sitting on a mooring while you go back to work for a week, but not if you reliving on the boat and cruising it.
You may have deceived yourself in believing it can cause you get it close enough in Summer.

A flooded bank can tolerate PSOC pretty well and likely will recover a lot of capacity during a equalization, but PSOC a Lifeline bank continuously and you'll kill it.

Let's see if this copied
http://www.pbase.com/mainecruising/image/162501080

Follow this link, it will show you that it took seven hours to charge a used lifeline battery from 50% SOC to 100% SOC at .15c. For my 660 AH bank, that is 99 amps, about twice what my 1,000 W array usually makes and then only for a couple of hours in the middle of the day.

First how many hours a day does your array make full power? Does it do that early in the morning when the bank is at a SOC that can accept it, or more likely early in the afternoon when it can't? Do you get regularly over 7 hours of useable Solar a day, year round?

Now I don't discharge my bank to 50% SOC and I assume you don't either, according to the Smart Gauge I wake up with it about 85%, but still cannot reliably get it back to 100% day in and out and know I won't for a large part of the year.

On edit, pretty easy to look up, depending on source Fl gets about 4.5 to 5.5 useable Solar hours per day average year round and that is for terrestrial panels that are always tilted correctly, most boats can't do that, so subtract some to me unknown time from that number, and it's not enough hours.

[sailorboy1]

As I said I'm not going to argue little history points of how I knowingly abused my batteries for years. I'm on shore power for the first time in over 6 months. I know when my batteries are charged based on both specific gravity and battery acceptance. If somehow you know my system better than me by reading little small cap things out of context on CF that is amazing. But based on my experience unless you have been using 200ah each night, if you can not get your batteries recharged on a regular basis with 1000w of solar you have problems and need to stop acting like a sailboat battery expert.

[a64pilot]

Why 200? Earlier you said in excess of 300 is what I can put back.
Likely it seems I use about 100 overnight, however I'm sure we use more in the day and that use has to be added to 100 I use at night, plus charge inefficiencies, you have to out more back in than you take out, this is not a perpetual motion machine.
Now if we used your 200 a night, plus logically another 200 during the day, then 1 KW can't make that much power, but again it's not how much power it can make, it's how many hours does it make it that will get you when the days grow shorter.

[a64pilot]

Originally Posted by Kenomac

64pilot and sailorboy,

I see a Spectra watermaker in your future. We have two which produce 34 gallons per hour. Fresh water is never an issue, and they're so quiet.... we sometimes forget they're running.

Ken based solely on me deciding the generator has to be run some during the week anyway, I'm going with an AC one, almost certainly a Cruise RO for its simplicity, ease of repair, off the shelf parts and mostly the product support I received for my fridge. So we will wash clothes, charge batteries and make water during generator runs. I have a big enough inverter to power the washing machine, but can't get the bank back charge without burning Diesel in either the main motor or the generator.
Noise won't matter as I'm sure I won't hear it over the generator and washing machine.

However if I were considering s D C one I do not think I would chose anything other than a Spectra especially with Tellie backing it up.

[john61ct]

So you have enormous usage of AH per day, and reducing usage is not an option.

Large enough solar WILL get you to true 100% full even in winter, but in your case "large enough" probably is not practical for a mobile use case.

So, gennie usage. You could choose to run for an hour or two each morning, and you will be able to get to 100% Full doing that.

Note no matter what, you need high CAR to get as much as possible out of the genny running, no matter when.

If you are not willing to do that most mornings, then your choice is to go as cheap as possible and replace often, OR pay for a bank chemistry that doesn't mind PSOC abuse.

LFP would be ideal and cost-effective long-term, but a very large investment up front.

Firefly Oasis is a good middle ground, high CAR for lead and tolerates PSOC well, just a "restore capacity" protocol to follow say once a month. And "only" $500 per 100AH, much cheaper than an LFP system.

Complete respect for going with cheap GCs instead, just know you're losing a decent CAR which will require longer, more frequent gennie runs.

[Higgo]

Well we don't want to be "one of those" the mandatory hour a day gen set cruisers. So it looks like FLA's might be the logical option.

I am thinking Trojan T105's, what is everyone's thoughts ... is there anything better? (and dont have costco in my area)

[a64pilot]

Hard to beat the Trojan's, but maybe you have a Sam's club?

I hope my next bank will be Life-Po, maybe I can keep this one healthy long enough to get there.
I would have expected a true drop in by now from somebody, but maybe the market isn't big enough for that?
By drop in I mean a bank with a BMS, you still would have to supply a charger that can be set correctly. Now I admit my experience is with decently large size Li-PO banks, like 1 KWH cave diving scooter batteries, not Monster Life-Po banks.
Now I have not been looking but expect we would hear all about it here.

[Higgo]

No Sams club ... im on Aussie soil

[sailorboy1]

Originally Posted by a64pilot

Why 200? Earlier you said in excess of 300 is what I can put back.

Yes I said that so I guess you really don't understand. If you start the morning at -200AH and your 1000W of solar during the day puts in +300AH , then you probably wouldn't get 100% charged because you continued to use power during the day. I know that my lowly 290W solar can do 100AH during the day and that due to daytime use I need to be at -30 to -40AH before the sun really starts going for solar to get to 100% charge.

But I doubt most average cruisers start each morning at -200AH if they were charged the day before. So 1000W solar is not enough only for the excessive power users (I used to think I was one of those since we watch a couple hours of TV/DVD each night but I must not be).

But I think what you really met by your partial use of want I said is that I'm wrong and that 1000W of solar isn't enough. Which just looking around at anchor and talking with other cruisers isn't so.

[Sailmonkey]

Originally Posted by Higgo

No Sams club ... im on Aussie soil

Go to a golf course and see where they get batteries for their carts?

[sailorboy1]

Originally Posted by Higgo

I am thinking Trojan T105's, what is everyone's thoughts ... is there anything better? (and dont have costco in my area)

I have the T105s now and they don't seem any different than the Deka off brand I before. I think the 6V golf cart battery market is so mature that the differences between brands and makes in real life are very very minor.

BTW - I water mine about every 6-8 weeks and the 4 batteries normally take a combined 1-2 cups of water to be full again. Not exactly high maintenance.

[john61ct]

Trojan T-105s are great. Rolls (Surrette) even better, but likely too dear.

[a64pilot]

Originally Posted by Sailmonkey

Go to a golf course and see where they get batteries for their carts?

They buy them by the pallet or more though, likely multiple pallets.
Maybe you can't get what they can, but it's certainly worth a try.

[john61ct]

Get friendly with the shop's boss and piggyback off their next order

[a64pilot]

Sailorboy I respect your knowledge, I really do.
However I'll say it again, it's not how big the solar array is, is the number of hours of charge you get in an average day.
Vast majority of cruisers are deep into partial SOC cycling. Talk to those that don't have Solar, they tell you their batteries are fine, they run the engine an hour every day.
See you can go from around 50% to around 85% pretty quick, maybe in that hour, but once you get around 90% it takes hours, and majority of chargers will never get you there either, they trip out into float way too soon. Batteries don't die an immediate death from partial charging it takes a considerable time.
If your a Lifeline AGM bank the only way to tell if your at 100% is to watch charge acceptance, once I see 3.3 amps plus my house load at absorption voltage, then I'm at 100%. I cannot rely on my Sterling charger, it always trips out early, my Magnum and Outback I can set to hold absorption voltage, the Outback is the only one charging with Solar only of course.