DC generator vs full solar/wind solution

[a64pilot]

On the charger and absorption thing.
I have two chargers, one works off of an algorithm and does indeed seems to kick into float a little earlier, the Magnum inverter / charger though you can program it to run X hours in absorption, or hold absorption voltage until X number of amps is reached. That is the ideal solution, as long as current draw is the same. I believe if I remember correctly that with no electrical draw on the bank, my 660 AH Lifeline bank should be held at 14.3 V until 3.3 amps charge is reached, then they are fully charge and you can switch to float.
So I have usually about 10 amp draw, so I have set the Magnum to end Absorption when 14 amps charge is reached

[gjorgensen]

Originally Posted by socaldmax

I'd love to find a solar controller and battery charger that would actually fully charge batteries, but since the solar recharge cycle starts up again at 8am every morning, maybe being 100% charged isn't such a big hairy deal after all.

I agree with all your points, but just wanted to point out this comment. The big deal about not getting a lead acid bank back to nearly 100% is sulfation. Not being able to top the bank will start to cut capacity of the bank due to sulfation. That happens with L-A over time anyway, but not getting the bank charged up makes it worse. Equalizing to bring the bank back takes a lot of sustained power so typically needs shore power or a generator.

I agree that a combination of as much solar as you can fit plus an AC generator makes the most sense, and would help alleviate this. Also, if you can swing it LiFePo4 batteries would make a huge difference - no problems with undercharging, and no Peukert effect so you can efficiently drive them to 100% charge. Over on the Lagoon groups there are boats that have 1500+ watts of solar and LiFePo batteries that are doing everything, including AC and washing machines, without a generator by using large inverters. As long as the sun shines that works great, but I still think having a small generator along with that makes more sense.

[a64pilot]

I've been wondering if it's not logical to have your Solar stay in absorption and never go to float.
If in fact Solar can't quite get you to 100% charge, why should it ever switch to float?

This on a boat actively being lived on and cruised, if your on a mooring and your nightly power usage is almost zip, then I would assume Solar can in fact get you to 100%

[a64pilot]

Yes, if you can go to Life-Po, then that is a different ballgame, I don't have Life-Po, but do understand the game is played under a different set of rules than an LA bank.
I expect my next bank will be Life-Po

[uncle stinkybob]

I've decided to go solar, 200 watt system. but I also bought a small 900 watt peak/700 watt running, generator from H.F. for charging battery's when need arise's. It runs around 5 hour's on a gallon at 50% capacity. Weight is less than 30 pound's, It's small, burns the same gas mix as my dingy outboard, and I can toss it in the dingy for power on shore if needed. I see them on special for less than $100.

[socaldmax]

Originally Posted by a64pilot

I've been wondering if it's not logical to have your Solar stay in absorption and never go to float.
If in fact Solar can't quite get you to 100% charge, why should it ever switch to float?

This on a boat actively being lived on and cruised, if your on a mooring and your nightly power usage is almost zip, then I would assume Solar can in fact get you to 100%

I don't see how you can do that. The solar controller automatically switches to float after it hits absorption V (cheap charger) or after 180 minutes (good charger.)

I don't know of any that will let you keep it in absorption mode. Perhaps you could try to trick it by setting float V at absorption V and setting absorption V 0.1V higher.

[socaldmax]

Originally Posted by gjorgensen

I agree with all your points, but just wanted to point out this comment. The big deal about not getting a lead acid bank back to nearly 100% is sulfation. Not being able to top the bank will start to cut capacity of the bank due to sulfation. That happens with L-A over time anyway, but not getting the bank charged up makes it worse. Equalizing to bring the bank back takes a lot of sustained power so typically needs shore power or a generator.

I agree that a combination of as much solar as you can fit plus an AC generator makes the most sense, and would help alleviate this. Also, if you can swing it LiFePo4 batteries would make a huge difference - no problems with undercharging, and no Peukert effect so you can efficiently drive them to 100% charge. Over on the Lagoon groups there are boats that have 1500+ watts of solar and LiFePo batteries that are doing everything, including AC and washing machines, without a generator by using large inverters. As long as the sun shines that works great, but I still think having a small generator along with that makes more sense.

Some of the solar controllers do an automatic equalization charge every 28 days or so.



On the topic of solar water heater, I was thinking of one that looks like this, but maybe half as long.

[a64pilot]

For Solar water heater, If you had the room, buy one at a pool store, they come in sections.
Pump wise I just threw away one that my old fridge used, a AB Super Cold machine, had a little water pump that drew very little power, I assume it would stand the heat?

[ColdEH]

Personally I would never put a solar panel on a pretty boat.

I run my generator for 2 hrs every 3 or 4 days on the hook . Lifepo4 batteries charge very fast and make 40 gallons of water at the same time . Live like at home . Micro wave , washing machine , hot showers , ......

Regards

[sck5]

Solar is way cheaper than the estimate I saw the OP make. I just put 280 watts on my bimini and all-in it cost around 1700 including the charge controller, remote monitor panel and all the hardware

https://www.emarineinc.com/280-Watt-...ra-140W-Panels

Of course if you pay somebody to install it you could probably double that cost but it is still way less than 5k

[socaldmax]

Originally Posted by sck5

Solar is way cheaper than the estimate I saw the OP make. I just put 280 watts on my bimini and all-in it cost around 1700 including the charge controller, remote monitor panel and all the hardware

https://www.emarineinc.com/280-Watt-...ra-140W-Panels

Of course if you pay somebody to install it you could probably double that cost but it is still way less than 5k

I installed an 1120 watt solar system recently for a customer, with 2x Morningstar 60 amp MPPT controllers and the very best marine wire, crimp connectors, heat shrink and custom powder coated brackets and all SS hardware and it came in around $4500, including all of my labor. The panels were just over $1200 with tax, the 2 controllers, hub and remote display were just over $1200, wiring and connectors were about $650, brackets were $300 or so due to custom design and primered powder coating, $100 in SS bolts, the rest was labor. We're expecting to see 80-85A in the summer, maybe 50-60A in the winter if he uses enough power.

I told him he could support a washing machine, if his wife wants it.

[socaldmax]

Originally Posted by typhoon

Personally I would never put a solar panel on a pretty boat.

I run my generator for 2 hrs every 3 or 4 days on the hook . Lifepo4 batteries charge very fast and make 40 gallons of water at the same time . Live like at home . Micro wave , washing machine , hot showers , ......

Regards

It depends on the boat, some of them can integrate some solar panels without looking like an oil rig.


How powerful is your battery charger? If you can pack that much power in running it only 2 hrs every 3 or 4 days, that's pretty impressive!

[sailorboy1]

Originally Posted by a64pilot

I've been wondering if it's not logical to have your Solar stay in absorption and never go to float.
If in fact Solar can't quite get you to 100% charge, why should it ever switch to float?

This on a boat actively being lived on and cruised, if your on a mooring and your nightly power usage is almost zip, then I would assume Solar can in fact get you to 100%

I've played with my solar controller the past 3 years. It seems that by the time the battery gets up to absorption voltage the charge acceptance is pretty low. By that I mean on my system on a sunny day with the boat facing the best way for the panel that when absorption voltage is reached the batteries are only accepting a low ampere (less than 1/2 of what the panel could/should be putting out and maybe less than 2% of the AH rating). So I feel the batteries are pretty close to full charged at the time. I have been holding the absorption for 1-hour or till the amps get down to 2 amps. I tried the system once with the absorption time set to 2-hours and all that seemed to change was that the batteries needed water more often.

This is for a boat out on a mooring with the freezer/refrigerator on all the time. I would say that it does the hour at absorption about 40% of the time, gets to absorption less than 1 hour another 30% of the time, and the rest gets close.

So maybe the batteries don't get fully charged each day, but at least 70% of the time get real close.

And I don't really feel that spending more on extra solar to get the batteries fully charged more often is a good money solution based on time/money of the batteries and solar costs.

[a64pilot]

I believe Lifeline says they are fully charged when the charge current is at .5% at absorption voltage, so for my 660 AH bank, that is 3.3 amps at 14.3V.
Your results may vary of course, plus my issue is that my Lifeline AGM batteries are way more $ per AH than most, and I believe less tolerant of partial SOC cycling than most.
So I feel I need to treat them a little better due to their cost.
I wouldn't have fit them, if I could have put Sams club golf cart batteries, but doing that would have required major surgery.

[sailorboy1]

Originally Posted by a64pilot

I believe Lifeline says they are fully charged when the charge current is at .5% at absorption voltage, so for my 660 AH bank, that is 3.3 amps at 14.3V.
Your results may vary of course, plus my issue is that my Lifeline AGM batteries are way more $ per AH than most, and I believe less tolerant of partial SOC cycling than most.
So I feel I need to treat them a little better due to their cost.
I wouldn't have fit them, if I could have put Sams club golf cart batteries, but doing that would have required major surgery.

Must suck to be a slave to a battery bank

I don't really believe that for the most part batteries get a lot longer life by getting to 100% than 98%. Even if they do I still question whether the extra life is worth all the extra worry etc.

I don't know why it would have been major battery surgery for you to have used the 6V batteries. Two 6V batteries fit into my 4D sized battery boxes with lots of space (height just barely made it for me though)