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Hello,

I am considering a serious upgrade to our electrical system basically to allow us to stay on the hook for 2 days without worries. I wanted to find out suggestions and recommendations and understand if those are reasonable goals.

Most of our consumption is refrigeration/freezer and anchor lights plus a few hours of lights at night (LED). Our system consumes about 5A when the fridge/freezer are running with the anchor lights, and that is enough to use 50% of capacity in less than 24h. This is on factory Beneteau Oceanis that is about 7 years old, so the batteries are nearing useful life (but are holding so far). Batteries are wet cell, 4 for house, 1 engine, 2 for the bow thruster. Charger is a Cristec CPS3 charger which seems to support AGM batteries as well. Engine is a Yanmar 3JH5E with what I believe is a Hitachi 80A alternator. Boat is in Seattle.

1) Is it reasonable for 48h on the hook with a reasonable cost system? More?
2) I tend to motor a lot in the summer, would a bigger alternator be a good investment? I have no generator. How about a much bigger alternator (200A)? Right now I have to motor well above 1000 RPM for several hours to get just a fraction of our capacity recharged.
3) Would typical solar (a couple of large panels over my Bimini) be meaningful in the Pacific Northwest? In other words, should I expect it to generate enough energy for a night? Less?
4) Would changing to AGM increase our capacity (keeping the same volume of battery) by a lot? a little?
5) any recommendations for chargers and alternators (Balmar?) I should look into for a modern sailboat? Any other reading ?

Thanks much for any help!
 

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Hello,

I am considering a serious upgrade to our electrical system basically to allow us to stay on the hook for 2 days without worries. I wanted to find out suggestions and recommendations and understand if those are reasonable goals.

Most of our consumption is refrigeration/freezer and anchor lights plus a few hours of lights at night (LED). Our system consumes about 5A when the fridge/freezer are running with the anchor lights, and that is enough to use 50% of capacity in less than 24h. This is on factory Beneteau Oceanis that is about 7 years old, so the batteries are nearing useful life (but are holding so far). Batteries are wet cell, 4 for house, 1 engine, 2 for the bow thruster. Charger is a Cristec CPS3 charger which seems to support AGM batteries as well. Engine is a Yanmar 3JH5E with what I believe is a Hitachi 80A alternator. Boat is in Seattle.

1) Is it reasonable for 48h on the hook with a reasonable cost system? More?
2) I tend to motor a lot in the summer, would a bigger alternator be a good investment? I have no generator. How about a much bigger alternator (200A)? Right now I have to motor well above 1000 RPM for several hours to get just a fraction of our capacity recharged.
3) Would typical solar (a couple of large panels over my Bimini) be meaningful in the Pacific Northwest? In other words, should I expect it to generate enough energy for a night? Less?
4) Would changing to AGM increase our capacity (keeping the same volume of battery) by a lot? a little?
5) any recommendations for chargers and alternators (Balmar?) I should look into for a modern sailboat? Any other reading ?

Thanks much for any help!
We have 6-6 volt AGM Lifelines for a total of 720 AH or 360 usable AH.
Our daily diet is 70 AH ( 46 AHrefrigeration, 8 AH lights ( LED,) pumps 6 AH, and 10 AH electronics, radar and chRging phones) 70 AH daily diet divided in to 360 usable AH means approx 5 days without charge. We also have a 12v AGM stRting battery echo charged off the big house bank.

Advantages of AGM is maintainence free, accept charge faster than wet cell, last longer if taken care of correctly, can be laid on side saving waste, no acid fumes.Negative is the cost . But if you figure they will last 8-10 years if used and charged correctly works out to cheaper than wet cells.

Master volt 3 stage programmable 40 amp shore power charger. 100 amp Balmar alternator with AR5 outside regulator with temp and heat loads.

Read up on electrical systems as important to match to you capacity so not to burn out alternator and not throw money away unnecessarily and understanding that after 85% full battery charging goes from bulk to absorption and slows down perceptibly.

I like 6 volt as they are liftable, and the plates are usually thicker thus having a great number of charges in the deep cycle generally

Fell free to PM me if you have any questions.
 

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Since you mentioned switching to AGMs, I’ll bet you currently have stock Gels. Beneteau group seems to like them. We have gels. They have some real advantages of being durable and long lived. However, they take charge slowly, so no matter how big your alternator is, they won’t necessarily charge any faster.

The biggest advantage to AGMs is how fast they take a charge, if you can produce it. This is also why you need three stage charge controllers and temp sensors off the alternator, so you don’t burn out an expensive alternator. While there are some edge case AGM brands that can live for extended periods on a partial state of charge, generally you’ll want to be able to get back to 100% frequently to maximize the life of the batteries. You want to be able to know you’re not using them below 50% SOC too, to extend longevity. Your 48 hr plan is very doable.

If you really want to get contemporary and are redoing the whole system (batteries, chargers, alternator, controllers, etc) think about LiFEPo lithium batteries. Read up.

Ultimately, to be on the hook, you want the ability to recharge. Love passive things like solar, but the sun doesn’t always shine. Start with a good alternator and charge controller and new batteries.
 

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OP needs to do some typical 24hr day load calcs and charge calcs. Do a worst and best case scenario (day and night as well).

Loads include of course:
lighting - interior and nav/exterior
nav instruments include radios, gauges (radar use time) AIS) w/ and w/o lighting
refer and freezer
inverter
galley appliances
entertainment - pc, tv, stereo
fans
heating (if it uses electricity)
autopilot
windlass
pumps (pressure water, shower sump & bilge(s)
assorted device charging
etc.

Current suppliers (battery charging devices include:
engine alternator
solar
wind
generator
etc.

Once you know the range of consumption of amps... you can size your batts to supply those amps.

As mentioned previously, to lengthen the service life of your batteries you DO want to limit the percent of discharge as much as possible... which means a large bank capacity with as few deep cycles as possible.
 

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Discussion Starter #5
Since you mentioned switching to AGMs, I’ll bet you currently have stock Gels.
Unfortunately not, they are wet and need fluid checks/top off.

Noted on fast charge up to 85%, multistage charge controllers with sensors.

On getting back to full charge I think that's easy for my usage (when I dock every couple of days it will always go back full overnight).

If you really want to get contemporary and are redoing the whole system (batteries, chargers, alternator, controllers, etc) think about LiFEPo lithium batteries. Read up.
I really dislike the idea of a fire that can't be extinguished, no matter how low the odds, so I think I'll wait another decade for this.

Thank you, I will look into 6V (which I assume you hook up so they look like 12 or 24 to the rest of the system).

As for a budget, we have no electrical equipment that consumes meaningful of power that we wouldn't give up on typical days we are on the hook, other than refrigeration anchor lights overnight and convenience LED lights for a few hours. And the propane solenoid that can burn an amp but we only use for an hour or two.

"Large bank with few deep cycles" is a good description of our usage so we would stay on the hook for two days, a deep cycle, go back to a dock, refresh everything, then repeat, or go for a day sail (which will not be a deep cycle).

As for solar panels, it seems 400W is a reasonable setup, but that would not be able to keep up with our usage of about 150Ah a day... but it could be close. How do solar panels and AGM batteries go together? Seems like they would prevent the deep cycle and never quite be able to top the batteries off until we dock? Does it mean we should get more aggressive on the panels to generate what we use? Avoid them?

Thank you for all the input!
 

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If you existing battery bank was in good shape I would think you should get more than 24hrs out of it with your relatively light load. Our Jeanneau has a similar setup to yours...same alternator, same charger, same loads. We have 5 x110ah flooded cell batteries. Last fall we spent 3 full days on the boat without charging, and we were running the diesel heater as well. At the end of the long weekend our house bank was just approaching 50%. I know you have 1 less battery, but you should be able to get more than 24hrs.

Your batteries may be at the end of their service life, but they may also just need some maintenance. Have you checked electrolyte levels? Even so called " maintenance free" batteries need maintenance! If electrolyte levels get low the plates won't be fully immersed, and you will lose capacity. Just topping up the cells with distilled water may bring them back to a certain extent, and buy you some time to plan your upgrade.

I have been contemplating upgrades and charging options myself, so I recently spent quite a bit of time at the boat show talking to exhibitors. As appealing as Lithium is, they are extremely expensive still, and will require a new charger and possibly a new alternator.

Another option that caught my attention was the Firefly batteries. They are a carbon foam AGM, and I am told that they can be discharged down to 35% instead of the usual 50%. They are quite a bit pricier than regular AGM, but they give you more capacity in the same footprint.

I would be interested to hear from anyone who actually has Firefly batteries.

Sent from my SM-G960W using Tapatalk
 

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I have a Beneteau 393 but it sounds like your boat is bigger (and newer). I will give my opinions below...

1) Is it reasonable for 48h on the hook with a reasonable cost system? More?
This is reasonable. You do not need more. Save your money.

2) I tend to motor a lot in the summer, would a bigger alternator be a good investment?
No. The engine specified alternator is the correct one for your boat. People often talk about huge alternators. I think theyre BS.

3) Would typical solar (a couple of large panels over my Bimini) be meaningful in the Pacific Northwest?
As many solar panels as you can fit. In summer high latitudes have many hours of usable sun. Also the cooler the pannel the more efficient it is. 400 watts (2 x 200 watts) would be enough.

4) Would changing to AGM ...
I think AGM are expensive BS (like Lithium) I will be shot at for saying this! :) :)

5) any recommendations for chargers and alternators (Balmar?)
Nothing more than you have. Save your money.


I wouldn't even change the battery bank... unless you do a stress test and they fail. Then I would replace with Sealed Lead Acid. Cheap/durable/maintenance 'free'.

One any weekend you are out if the volt meter drops lower than 12.2 start the engine for an hour. You will get used to your boat quickly and adjust to it. If, then, you really, really need to upgrade/replace stuff you will be doing it with a basis of knowledge. If you do it now you could well spend over $5,000 *unnecessarily*. And thats the punch... unnecessarily.

Now you've read this please realise I am not a marine electrician. I often ask questions here because I get into all sorts of problems. So read all responses and sort out the best info :) And ask more questions :)




Mark
 

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2) I tend to motor a lot in the summer, would a bigger alternator be a good investment?
No. The engine specified alternator is the correct one for your boat. People often talk about huge alternators. I think theyre BS.

A bigger alternator might not be a good investment, but a different alternator would be. That Hitachi is about the worse choice for charging. An 80A of any other brand, externally regulated, would provide much more charging than the OEM Hitachi.

3) Would typical solar (a couple of large panels over my Bimini) be meaningful in the Pacific Northwest?
As many solar panels as you can fit. In summer high latitudes have many hours of usable sun. Also the cooler the pannel the more efficient it is. 400 watts (2 x 200 watts) would be enough.

Having lived full-time on a boat for many years with 150Ah daily usage and 480W of solar, I can definitely say that 400W in the PNW will only be enough in rare long days with lots of sun. Other times of years or environment conditions it will not be enough.


I wouldn't even change the battery bank... unless you do a stress test and they fail. Then I would replace with Sealed Lead Acid. Cheap/durable/maintenance 'free'.

The first sentence I agree with, but the second one is bad advice. Those are just cheap automotive batteries, and for the same price one can get much better golf cart batteries, or pay up for a real deep cycle battery.

One any weekend you are out if the volt meter drops lower than 12.2 start the engine for an hour. You will get used to your boat quickly and adjust to it. If, then, you really, really need to upgrade/replace stuff you will be doing it with a basis of knowledge. If you do it now you could well spend over $5,000 *unnecessarily*. And thats the punch... unnecessarily.

Personally, I would get annoyed at starting my engine several times a day (which you will be doing with the above). I do agree with putting off any real investment in this until you have a very deep understanding of how you are using the boat and what you need it to do.
[/QUOTE]

I'm unsure why you think AGM will give you more capacity? Capacity is mostly determined by size, not by type - given equal comparison, and not a car starting battery vs deep cycle AGM, of course.

As for AGM taking a charge faster, this is very, very, rarely true because most boats don't have the charging capacity to max out flooded lead batteries, and AGM only accepts high current for a short time before falling back to flooded rates. I guess if you have a small battery bank and a large charging source, AGM might save you a bit of time in charging - but even then, not very much at all.

For example, a 400Ah flooded battery bank will easily take 100A of charge current. Most boats struggle to supply even that, let alone the 200A an AGM will take for a half hour or so.

Personally, I think AGM is about the worse choice of a boat battery. If you need to shove them somewhere without maintenance, then gel batteries are better. They are better even if you don't need this. Otherwise, flooded are inexpensive and rugged. Lithium is the best choice in the strictly narrow term of what is the best battery for a boat - no other consideration taken into account - but it is not a good choice for you right now, nor for many people ever.

Solar won't have any negative effect on any battery type you choose in any way. Solar is all positive effect all the time.

I would bet a donut your batteries are toast, and an equal capacity bank of good ones would not have you asking some of these questions because they wouldn't have occurred to you because the batteries were filling your needs.

Mark
 

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https://roadslesstraveled.us/wet-cell-vs-agm-batteries-rv-installation-wiring-tips/

Taken from an article by Trojan a known maker of top quality wet or AGM batteries

AGM batteries are maintenance free, which means:
1-They don’t need periodic equalizing to clean the internal plates and never need the electrolyte topped off with distilled water.
2-They do not release gasses during charging, so they don’t need special venting in the battery compartment.
Since gasses are not released, the terminals and battery cables do not corrode over time and don’t need to be cleaned.
3- AGM batteries discharge more slowly than wet cells, so an RV or boat can be stored for a few months without charging the batteries.
4- AGM batteries charge more quickly than flooded batteries because they can accept a higher current during the Bulk charging phase.
5-AGM batteries can be installed in any orientation, which is helpful if installation space is limited.
6-AGM batteries can’t spill battery acid if they are tipped over. This is especially important when a boat heels excessively or capsizes.

You have received a number of suggestions, but like a subject on anchors we all post on what our own experiences are. The are merely opinions of amateurs, me included. ��

[B]https://marinehowto.com/[/B]

One thing I would suggest is that you read through the electrical library of items created by one of our Sailnet members .....Maine Sail. He is an expert on this stuff as it actually is his profession. Before spending lots of money on electrics it’s good to educate so you can make a good decision. The website is posted above, and he will answer your questions if posed to him on SN through IM. I spent of lot of time being educated by both he and SVAuspicious who used to be on Sailnet before I dropped an extra dime on electrics.
 

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....I really dislike the idea of a fire that can't be extinguished, no matter how low the odds, so I think I'll wait another decade for this.....
Then you shouldn't have any batteries aboard. They can all catch fire and/or explode, if handled improperly. Read up on the difference between lithium ion and LiFEPo. The latter are not the same as old tech lithium. Although, I’m not intending to sell you on the idea.
 

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Discussion Starter #11
You're probably right on on tired batteries, but we do top them off with water at least twice a year.

We measure charge left with Smart Gauge (from Balmar). I don't know how reliable that is, but that's where we see us get from 100% to 50% in one day.

Thanks for the tip on the Firefly, the extra 15% seems like a great advantage. I will price that too.
 

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Remember that wet cell batteries MUST be equalized regularly in the season to desulfate the lead plates. If they are not the batteries literally suffocate. This limits their life expectancy and also can limit the ant of charge they will hold.

A good three step charger will have directions

The reason I recommend 6 volt batteries ( golf cart) is that they have more cycles In them generally.

Also AGM you doN’t need the battery boxes to prevent spillage of acid and they don’t give off hydrogen sulfide gas.

The alternator should be matched to the size of the battery bank. Your 80 seems fine, but a better brand would give you better performance, and having a temp sensor prevent it from frying. While many alternators come with internal regulators, the AR5 is programmable and it’s electronic readout gives you an idea how the alternator is performing As it has a readout in the cabin. Internal regs don’t have that. It can help in checking efficiency and as a diagnostic meter.
 

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4- AGM batteries charge more quickly than flooded batteries because they can accept a higher current during the Bulk charging phase.
This is true for as far as it goes - they CAN accept higher charge more quickly in the BULK charging phase. But in practice, almost nobody can provide that higher charge, and the bulk phase is so short as to be meaningless in the timeframe of a full charge.

For a 400Ah bank, flooded batteries will take 100A of charge in bulk phase, while AGM will take 200A. How many boats here can even supply a continuous 100A for flooded, let alone 200A for AGM?

Then the short bulk phase is the only part of the charge cycle where AGM sprints ahead (assuming one can generate enough charge current for it). The rest of the charge cycle takes the same time regardless of battery type.

Mainesail actually did the experiments: https://marinehowto.com/how-fast-can-an-agm-battery-be-charged/
When sufficient charge currents can be supplied to take advantage of the AGM faster bulk charge rate, the AGM's charge a whopping 12 minutes faster than flooded over 5.5hrs of charge time to full.

Put another way, AGM's charge 3.6% faster than flooded.

Remember that wet cell batteries MUST be equalized regularly in the season to desulfate the lead plates. If they are not the batteries literally suffocate. This limits their life expectancy and also can limit the ant of charge they will hold.
This isn't true. We have had flooded batteries for many, many years and they never needed equalizing. The flooded battery in everyone's car never needs equalizing.

ALL lead chemistry batteries will sulfate if not charged fully regularly, or is discharged too deeply regularly. Flooded and AGM, treated the same way, will sulfate themselves to death in the same manner.

The only difference is that equalization CAN be done with flooded, so some mitigation of damage can be performed.

Mark
 

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Mainesail actually did the experiments: https://marinehowto.com/how-fast-can-an-agm-battery-be-charged/
When sufficient charge currents can be supplied to take advantage of the AGM faster bulk charge rate, the AGM's charge a whopping 12 minutes faster than flooded over 5.5hrs of charge time to full.

Put another way, AGM's charge 3.6% faster thanmany years and they never needed equalizing. The flooded battery in everyone's car never needs equalizing.

Mark
That test had nothing to do with flooded batteries. It was AGM to AGM when charged at .2C and .4C..

Total time from 50% to 100% SoC was only 12 minutes apart. However, at .4C for one hour 87% was achieved and .4C for two hours 96% SoC was attained. The last 4% is very sloooow...
 

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That test had nothing to do with flooded batteries. It was AGM to AGM when charged at .2C and .4C..

Total time from 50% to 100% SoC was only 12 minutes apart. However, at .4C for one hour 87% was achieved and .4C for two hours 96% SoC was attained. The last 4% is very sloooow...
My mistake. I thought I remembered you did an article about AGM vs. FLA in same manner, and found that one quickly without further looking.

So at 0.2C, would an AGM charge any faster than a FLA? If not, one could use transitive logic to come to the same conclusion as I attributed to your study.

The point remains valid that most boats don't have charging systems to operate off grid at 0.4C. Many can't reach 0.2C. Even on the grid, where charging rate is mostly meaningless, most can't generate 0.4C, and many not even 0.2C.

Mark
 

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TLDR;

The FIRST upgrade that I would make to the OP's boat is a Balmar multi-stage voltage regulator. See Multi-Stage Regulators | Balmar

Spend some time getting it dialed in for your boat.

The charger that you mention (Cristec CPS3) is a SHORE POWER charger. This is not all that important if we are talking about power while away from the dock.
 

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TLDR;

The FIRST upgrade that I would make to the OP's boat is a Balmar multi-stage voltage regulator. See Multi-Stage Regulators | Balmar

Spend some time getting it dialed in for your boat.

The charger that you mention (Cristec CPS3) is a SHORE POWER charger. This is not all that important if we are talking about power while away from the dock.
Good advice.

We have an AR5 Balmar and it gives us a great indication of what is going into the batteries from the alternator.

https://shop.pkys.com/Balmar-ARS-5-H-Regulator-12-Volts_p_1734.html?gclid=EAIaIQobChMIlLLN_IfZ5wIVkovICh1EoQJ1EAAYASAAEgILQPD_BwE

Even if you buy new batteries this piece of equipment is a good thing to have no matter which direction you go and the monitor is a good way to measure the metrics / health of your onboard charging system. $300 is a small price to pay when adding to the overall i prom Ent of your electrical system. It give you great info. It will not be absolute and is a great addition.

Conditioning a battery is a time tested way MANY of us use to keep our batteries in tip top shape. Very easy to do with most shore power chargers in to days world. It’s is a way to prolong your life. Since the OP will have access to shore power most of the time it’s a great procedure to do every couple of months or more often should the batteries warrant it. It was also be termed as equalization in some circles. Many cruisers don’t do this because they don’t have the SP availability like you do.

As you educate yourself on the total picture through your reading, it can become apparent that there are many right opinions and some have to do with the type of sailing / facilities you have. The electrical system of your boat can be very expensive and easy to waste money on ( as well as time changing stuff) if you don’t match items as well as systems that work for your particular way of sailing.

We are weekend sailors with two or three 10-14 day cruises thrown in in a year. Our 33 weekends plus these cruises usually nets us 2-3 k nm a year.
We don’t have solar cells, but have thought about it. We have a 100 amp alternator and a good shorepower charger as Haleakula spends time in a slip a lot. We have a large battery bank at 720 ah of 6-6volt Lifeline AGM because we never wanted to worry about power again . Sounds like your situation. We have limited space so AGM work for us. No need to add water. If handled properly in a thought out system need no replacing in 10 years.
No need for added battery boxes to contain potential acid . No need for expose to Hydrogen sulfide gasses , the by product on wet cells. If you don’t maintain the wet cells you will replace every 2-3 years. Hard to mess up maintaining AGM. 6 volts can be combined into 12 volt units. 6 volts usually mean thicker plates so more cycles. 6 volts are easily moved by a person as the weigh 50-70 lbs and are not bulky. Our 6 volt Lifelines can be equalized, and we do. They can cost $220 apiece but you must look for deals and discounts.

Remember usable ah is generally 1/2 their over ah rating. That’s the figure you divide into with your sails electrical diet. Your figure of 150 ah daily seems excessive. The reefer doesn’t run 24/7 usually . The only was to truly tell is to also have a battery monitor to give actual readings.

I would think a 440 ah system ( 4- 6 volt or 4- group 31) would be plenty for your weekend use. Charging batteries by running the engine for how we sail is a useless and expensive way to recharge batteries. Get a large enough bank so you don’t have to do that for 2-3 nights on the hook. If you got the type we used that would be 480 ah ( 240 usable).

You could also eventually make you refrigeration more efficient with insulation. Another project lol.

The key is to slowly build a well matched system. Not complicated but I like it to be as trouble / maintenance free as possible.

Firefly look promising but even more expensive than our lifeline AGM

https://www.pysystems.ca/resources/tech-talk/carbon-foam-batteries-real-world-installations/

Lots of info.....lol😀
 

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.....The charger that you mention (Cristec CPS3) is a SHORE POWER charger. This is not all that important if we are talking about power while away from the dock.
True, but if the OP moves to AGM, they'll want to insure this charger has an AGM profile setting, for when they are back at the slip. I have a funny feeling, it's a poor shore charger. They aren't made anymore and I have a feeling they aren't three stage chargers, other than perhaps on a timer. I have some old Cristec's that charge the accessory batteries, but disconnected the house bank charger and replaced it with a Magnum Inverter/Charger.
 

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Back to the OP's original questions;
1) Is it reasonable for 48h on the hook with a reasonable cost system? More?
Absolutely YES!
2) I tend to motor a lot in the summer, would a bigger alternator be a good investment? I have no generator. How about a much bigger alternator (200A)? Right now I have to motor well above 1000 RPM for several hours to get just a fraction of our capacity recharged.
BEFORE buying a new alternator, make sure that you are making the best use of the alternator and batteries that you have - thus my suggestion that he get a multi-stage voltage regulator. This is especially true if he is motoring a lot.
3) Would typical solar (a couple of large panels over my Bimini) be meaningful in the Pacific Northwest? In other words, should I expect it to generate enough energy for a night? Less?
Solar would /could help. However, I suggest that he start with getting the alternator and voltage regulator squared away first. I have added a small , portable, 60 Watt folding solar panel on my much older, much smaller boat. I use the solar panel to help keep my batteries above 60% SOC (per my SmartGauge - which is a whole other can of worms), and it does a fine job of this on sunny days. The primary load is from my Dometic self-contained 12V refrigerator, which seems pretty efficient to me. This little panel keeps up with my power draw in Rhode Island during the day. The panel cost me ~$130 (now <$100) including a MPPT controller... but this is getting away from his question.
4) Would changing to AGM increase our capacity (keeping the same volume of battery) by a lot? a little?
I believe that others have already pointed out that AGMs would charge quicker. However, installing AGMs WITHOUT either (a) adjusting the voltage output of his Hitachi (assuming that this can be done) or (b) adding a multistage regulator would be to set himself up for disapointment as the AGM batteries would likely die prematurely. I see this frequently in the Tacoma truck forums from owners that wanted "the best battery" because their OEM battery died after 4 years. Three years later they are *****ing about how Optima batteries are junk because they killed them in their Tacoma by not adjusting the alternator output.
5) any recommendations for chargers and alternators (Balmar?) I should look into for a modern sailboat? Any other reading ?
Read up on Balmar voltage regulators at the link that I posted earlier, and this one from Maine Sail; https://marinehowto.com/programming-a-balmar-voltage-regulator/
 
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