Best way to charge domestic batteries???

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Brent

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I have followed various threads on the forum regarding this subject, visited numerous sites dealing with charging systems. My knowledge is better now but …. Not clear enough to allow me to go forward with confidence. I bought our current boat last year and she needs TLC. Battery area is a disaster, having a generator to change the domestic batteries. The genny is u/s and I want a greener solution. Current alternator changes the cranker/domestic, it’s a 90 amp job (I did say it’s a disaster) . There is a 800 amp hr domestic battery bank connected to a good 230 ac shore powered system when in the berth. I want to fit a second alternator plus either solar panels/wind generator to allow long periods of independent sailing. Any advice on the best way forward will be very gratefully received. Live aboards.... you must have the answer!!! please tell!!
 
Generator, preferably diesel built in water cooled, 100 amp three stage charger, replace engine alternator with a balmar 100amp alternator, (although the 90 amp already fitted should do, if in good nick) smart alternator regulator, Split relay or diode splitter (if the smart regulator will remtely sense the voltage) 160 watts of solar panels (2), a wind/water generator, Sterling or similar battery monitor system, that about covers it.
 
I understand your reply, don't agree. Not everyone (including me) look at all forums. I just want to capture a wide audience from forums that I feel can help and get the benefit of the wealth of knowledge out there.
 
My thoughts, for what they are worth:

Most important:

battery monitor - not really worth doing too much till you know what effect its having - sterling one seems ok - make sure you fit it properly as its obviously important to know whats going in as much as whats going out.

Next for me would be a smart charger - something that makes your alternator work at its best. If you dont want to take the alternator apart (not always required) Sterling do a device called and alternator to battery thingy which does the trick really well - at least on our boat.

Consider charging volts- can you charge at high level and replace the water in your batteries.... fast charge = loss of water (see sterling power FAQs) If you can, then consider leaving any solar panels you buy, unregulated and just keep an eye on the water levels.

Solar - great in daytime and when sunny but have very limited effect when partly obscured (some are ok) Total power over 24 hrs is likely to be less than you think but I still run four and they help a lot.

Wind gen - if sailing in the med - not as useful. If planning on the carib, they are just great! A decent one gives loadsa power.

For long passages we run a towed gen - at 6-8kts it can power our autopilot and fridge by itself. When we want to do a bit of HF stuff or similar or when we run down a bit we use other methods to recharge.

Finally - I'm sure you have come across this in your search for knowledge but one thing I have found very important is the following - The aim of the game is to only let your batteries capacity drop by a very small percentage of their total capacity before recharging. The smaller this percentage, the longer they will last. If you let them drop to 50% of their full capacity, they wont last very long at all. Hence monitor your usage and recharge by whatever method accordingly.

Big wires are also important to stop losses.

I know this has probably been said before but for the benefit of this gentleman, this is my first (and probably last posting on the subject!) Oh and I know some of it is open to debate but this is solely based on our experiences!

Cheers all!!!!!!!

Hope this helps. Feel free to PM me if you would like more info about what worked and didnt.
 
Start at the other end!! Eveyone has slightly different setups and most work but the 'Best' solution is one designed specifically for your boat. If you run seperate fridge, freezer, two computers large inverter etc etc then you need a different setup to the one for the boat with oil lamps and a sextant. If you look at the recent arc reports you see referrences to people running gernerators for 3/4hr per day as well as solar panels etc because they burn 3/400a/h per day down to one person who carried a small solar panal and foud it gave enough juice for his needs. Roughly speaking at under 50a/h day you can look at solar/wind power as primary power. At 50 to 150 you should find the main engine alternator is an adequate power plant suplimented by solar/wind. at 150+ you are in the relm of genorators. Then make it all twice as chunky as you think you need and put it in the dryest place you can. Make it all accessible and easy to monitor. Most problems come from either cutting corners, making it two small or out f balance 9like trying to run a 500a/h bank of a 40 amp alternator. The other pitfall is not installing good control monitoring gear. The battery monitor and charge regulators are vital parts of the system. A lot of what you have may just need servecing and reinstalling with ne wiring, the 90a alternator for example is ideal for batt banks up to about 500a/h.
 
did you think i was disagreeing with you Englander? not at all! I must have hit the wrong button. Was just apologising for furthering a post that had been done before. Sorry for confusion.
 
No, No, sorry if it sounded wrong, I was just saying I'd already said that, sorry if you thought I was being bad, didnt mean to.
 
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