Ok, I have to buy batteries, I was planning to buy seagel or any kind of gel battery, but not sure what size to buy . I want to make sure I buy ones with plenty of power for all the accessories I want to install along the way. I was thinking of buying a smaller one just for the engine, like an 24 group and a larger one for the accessories like an 27or31 group, then I could always add another one if I need it right. I know eventual I want to install solar or wind generator to charge them.but I don`t want to buy so big of batteries I`m going to need really large size solar or wind units $$$$. I guess my question is... What size batteries do the newer boats have in them,?because they already have all the accessories that I would like to have. And what size of solar or wind generators would I need to keep them charged ? Thanks ,chet
what size batteries to buy ?
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Wow Chet...
That's a big question. First we need more information. What size boat? How much do you plan to use the boat? What things do you have on board that use electricity? How many hours are you going to use those items that use electricity? Once you answer those questions you will come up with total daily amp draw. From that you can figure out the answers to the rest of the questions. There are several good books that you can buy that will help you answer the questions you have so you can build a system that will be reliable and managable. Dan
That's a big question. First we need more information. What size boat? How much do you plan to use the boat? What things do you have on board that use electricity? How many hours are you going to use those items that use electricity? Once you answer those questions you will come up with total daily amp draw. From that you can figure out the answers to the rest of the questions. There are several good books that you can buy that will help you answer the questions you have so you can build a system that will be reliable and managable. Dan
battery choices
to state the obvious, you need a battery or batteries large eough to provide the capacity to power everything you have. Not knowing what you have means it's impossible to tell what size capacity you need. Figure out your daily power consumption, multiply by 2 or 3 and that is a gross approximation of the capacity you should have. Your batteries will operate off one charger meaning, unless you get a multi-bank charger or eco-charger, all batteries should be the same size. If not, your charging will not be equally distributed shortening the life of all batteries.
to state the obvious, you need a battery or batteries large eough to provide the capacity to power everything you have. Not knowing what you have means it's impossible to tell what size capacity you need. Figure out your daily power consumption, multiply by 2 or 3 and that is a gross approximation of the capacity you should have. Your batteries will operate off one charger meaning, unless you get a multi-bank charger or eco-charger, all batteries should be the same size. If not, your charging will not be equally distributed shortening the life of all batteries.
more power or longer life.
Chet: I just went through a similar dilemma. I contacted a local company that sells just about anything that I wanted. My criteria is that I wanted a trully maintenance free system. This gave me two basic choices (AGM or GEL). The difference was total usable capacity or longevity. The AGM solution provided more usable power and the GEL solution provided better longevity. Regardless of the path that you take a good charging system is going to be high on your list of options. If you cannot properly charge and maintain your system it is not going to be satisfactory. We ended up with 2 G31 GEL's for the housekeeping end and an Optima starter battery. We also purchased a new charger (Xantrex XC 30 amp). This charger will allow you to charge 3 different battery chemistries on a single charger. So far so good. We got 10 plus years on our last set of GEL batteries (different boat) so I hope to duplicate the life of this system. You will need to do a power consumption analysis to determine how much power you will require. Remember that you can only use approx. 50% of the power that you purchase.
Chet: I just went through a similar dilemma. I contacted a local company that sells just about anything that I wanted. My criteria is that I wanted a trully maintenance free system. This gave me two basic choices (AGM or GEL). The difference was total usable capacity or longevity. The AGM solution provided more usable power and the GEL solution provided better longevity. Regardless of the path that you take a good charging system is going to be high on your list of options. If you cannot properly charge and maintain your system it is not going to be satisfactory. We ended up with 2 G31 GEL's for the housekeeping end and an Optima starter battery. We also purchased a new charger (Xantrex XC 30 amp). This charger will allow you to charge 3 different battery chemistries on a single charger. So far so good. We got 10 plus years on our last set of GEL batteries (different boat) so I hope to duplicate the life of this system. You will need to do a power consumption analysis to determine how much power you will require. Remember that you can only use approx. 50% of the power that you purchase.
Production-usage=storage
Here we go again. A lot has to do with the way you use your boat. A sailor that lives tied to the shore power cable 5 days a week and then uses the batteries on weekends has a totally different battery size and electrical generation problem than a sailor who wants to stay at a remote anchorage for extended periods of time. The quick and dirty concept is the batteries have to get you through till you can produce electricity to recharge them. Solar and wind have unpredictable production schedule but you will get something from them every day. A high output alternator will have a very predictable production of electricity but is noisy and uses precious resources you are trying to husband. A couple of things to keep in mind: batteries should only be drained to 50% capacity reducing your consumption is the cheapest way to reduce your $$$$ expenditures wind generators don't work in that "perfect" snug little cove completely sheltered from the wind. If you are going to use an engine to recharge your batteries why not use the extra ponies to generate AC, cool the reefer, cool the cabin, heat the hot water, refill the scuba tanks, run the watermaker...... While wind, water and solar power generation are great from a bang for the buck standpoint you really can't beat the cost of diesel fuel. To answer your question buy the biggest batteries that fit in your box. They will last longer and work easier. Also get rid of your starter battery and convert the space to another deep cycle bank. Starters only draw 50-75 amps. The spouse drying her hair pegs the inverter at 1000 Watts or 83 amps and that is for 2-3 minutes. When was the last time you cranked your engine for 2 minutes solid? Deep cycle can handle starter loads for the smaller engines sail boats have. I have a spreadsheet I developed that let me easily play with the loads and battery size relative to how you use and recharge them. If you would like a copy drop me a line @ roosaw@verizon.net
Here we go again. A lot has to do with the way you use your boat. A sailor that lives tied to the shore power cable 5 days a week and then uses the batteries on weekends has a totally different battery size and electrical generation problem than a sailor who wants to stay at a remote anchorage for extended periods of time. The quick and dirty concept is the batteries have to get you through till you can produce electricity to recharge them. Solar and wind have unpredictable production schedule but you will get something from them every day. A high output alternator will have a very predictable production of electricity but is noisy and uses precious resources you are trying to husband. A couple of things to keep in mind: batteries should only be drained to 50% capacity reducing your consumption is the cheapest way to reduce your $$$$ expenditures wind generators don't work in that "perfect" snug little cove completely sheltered from the wind. If you are going to use an engine to recharge your batteries why not use the extra ponies to generate AC, cool the reefer, cool the cabin, heat the hot water, refill the scuba tanks, run the watermaker...... While wind, water and solar power generation are great from a bang for the buck standpoint you really can't beat the cost of diesel fuel. To answer your question buy the biggest batteries that fit in your box. They will last longer and work easier. Also get rid of your starter battery and convert the space to another deep cycle bank. Starters only draw 50-75 amps. The spouse drying her hair pegs the inverter at 1000 Watts or 83 amps and that is for 2-3 minutes. When was the last time you cranked your engine for 2 minutes solid? Deep cycle can handle starter loads for the smaller engines sail boats have. I have a spreadsheet I developed that let me easily play with the loads and battery size relative to how you use and recharge them. If you would like a copy drop me a line @ roosaw@verizon.net
Thanks Ross, and ........
Dan, I know its an big question, but I wasn`t sure how to ask it, is a 30ft. I would like to add an ice box cooler , radio,be able to use my labtop,cabin lights,electonics,would like to buy an converter to convert hotwater heater,etc.I want to eventuraly try living aboard. this is all down the road though for me. as to i don`t make tons of money,but I don`t mind spending for good batteries if there going to last longer. Thanks for asking though,
Dan, I know its an big question, but I wasn`t sure how to ask it, is a 30ft. I would like to add an ice box cooler , radio,be able to use my labtop,cabin lights,electonics,would like to buy an converter to convert hotwater heater,etc.I want to eventuraly try living aboard. this is all down the road though for me. as to i don`t make tons of money,but I don`t mind spending for good batteries if there going to last longer. Thanks for asking though,
Batteries should always...
be installed at the same time. Even if it's the same brand but a year later it's not a wise move to add one at a later date. If you wnat the most bang for your buck 6V golf cart batteries give the most ah for the foot print and they are very inexpensive. 4 6V golf cart batteries will give you 450 ah and two will give 225ah. Golf cart batteries last a long time due to the size of the lead plates when compared to standard 12v batteries. What's your daily load calculation??
be installed at the same time. Even if it's the same brand but a year later it's not a wise move to add one at a later date. If you wnat the most bang for your buck 6V golf cart batteries give the most ah for the foot print and they are very inexpensive. 4 6V golf cart batteries will give you 450 ah and two will give 225ah. Golf cart batteries last a long time due to the size of the lead plates when compared to standard 12v batteries. What's your daily load calculation??
Ther are more questions here than answers.
Chet when you get down here we will have you over to Bietzpadlin. I think that we can answer a lot of your questions then. We use a pair of group 31 AGM batteries for the house and a group 24 for the engine. We have a very small demand so you can't go by what we use.
Chet when you get down here we will have you over to Bietzpadlin. I think that we can answer a lot of your questions then. We use a pair of group 31 AGM batteries for the house and a group 24 for the engine. We have a very small demand so you can't go by what we use.
Charging capacity another factor
There's not much point in installing a large battery bank unless you have the ability to keep it properly charged. I have a small diesel with a 35 amp alternator in my boat, and want to be completely independant of shore power, so of necessity my electrical loads & system has to be very modest. Otherwise, the engine has to be running much of the time, which kindof defeats the purpose & pleasure of a sailboat. If you're at a slip & frequently plug in to shore power, you can cheat a bit and increase the electrical loads somewhat, but if you can't keep the system properly charged with your on-board resources then your ability to go cruising will be compromised.
There's not much point in installing a large battery bank unless you have the ability to keep it properly charged. I have a small diesel with a 35 amp alternator in my boat, and want to be completely independant of shore power, so of necessity my electrical loads & system has to be very modest. Otherwise, the engine has to be running much of the time, which kindof defeats the purpose & pleasure of a sailboat. If you're at a slip & frequently plug in to shore power, you can cheat a bit and increase the electrical loads somewhat, but if you can't keep the system properly charged with your on-board resources then your ability to go cruising will be compromised.
Ross
is Bietzpadlin located there in perryville? I have to buy at least one before the lauching date April30. The prices from Defender ar`nt bad, I thought. Thanks for all the feedback from everyone,guess I have alittle more thinking to do before I`m ready to buy.huh.
is Bietzpadlin located there in perryville? I have to buy at least one before the lauching date April30. The prices from Defender ar`nt bad, I thought. Thanks for all the feedback from everyone,guess I have alittle more thinking to do before I`m ready to buy.huh.
TT
Thats a good thought, I to want to get to the point where I`m not depending on shore power to charge the batteries. I want to move aboard someday and spend some time living at the FL.Keys at key west, I was down there last winter looking for a boat for an live aboard but came up short in my price range.And for me to live there means either living on the hook or at the city mooring. chet
Thats a good thought, I to want to get to the point where I`m not depending on shore power to charge the batteries. I want to move aboard someday and spend some time living at the FL.Keys at key west, I was down there last winter looking for a boat for an live aboard but came up short in my price range.And for me to live there means either living on the hook or at the city mooring. chet
Golf cart batterys and a 110 Alternator
Putting my two cents in, I have a 33.5 Hunter with a 3 cyl. Yanmar 3gm30. I took the two gel batterys out and put 4 golfcarts in their place. I am about to change the stock 80 amp alternator for a 110 amp Balmar with a staged regulator, which should charge them in a reasonable time. Note that any alternAtor over 110 requires a larger pully/two belts to run, so plan accordingly. Alternator and regulator cost $550. Batterys are approx. $ 65 each Plus tax.
Putting my two cents in, I have a 33.5 Hunter with a 3 cyl. Yanmar 3gm30. I took the two gel batterys out and put 4 golfcarts in their place. I am about to change the stock 80 amp alternator for a 110 amp Balmar with a staged regulator, which should charge them in a reasonable time. Note that any alternAtor over 110 requires a larger pully/two belts to run, so plan accordingly. Alternator and regulator cost $550. Batterys are approx. $ 65 each Plus tax.
B.R., I cannot disagree more about elimination..
Bill: I cannot disagree more about the elimination of the starter battery. A small Optima battery can be your savior in an emergency. These batteries about about 2/3 the size of a G24 and may be the difference between life and death in certain conditions. I agree with you regarding the size of the battery bank. As long as you can charge it up in a reasonable amount of time (bigger is better).
Bill: I cannot disagree more about the elimination of the starter battery. A small Optima battery can be your savior in an emergency. These batteries about about 2/3 the size of a G24 and may be the difference between life and death in certain conditions. I agree with you regarding the size of the battery bank. As long as you can charge it up in a reasonable amount of time (bigger is better).
self sufficient Chet
I have a 2004 H33 with 3x130ah Trojan deep cycle lead acid house batteries and one 70ah starting battery. Three Sharpe 80 watt solar panels on the arch provide all the power for self sufficiency. I don't even bother to plug into the mains in the berth and keep the fridge running 24/7. My daily consumption when cruising including anchor lights at night is around 70ah per day and usually I am minus around 35ah at daybreak. On a sunny day am back to positive by 10.00am. The panels will put in around 15 amps max. On our last 10 day cruise I did not have to run the motor once apart from getting in and out of the Marina, what quiet bliss!. Worst situation on another trip was three days of continuous rain and got to minus 120ah but was back to positive after two cloudy but not rainy days. Why anyone wants gensets or big alternators is beyond me.
I have a 2004 H33 with 3x130ah Trojan deep cycle lead acid house batteries and one 70ah starting battery. Three Sharpe 80 watt solar panels on the arch provide all the power for self sufficiency. I don't even bother to plug into the mains in the berth and keep the fridge running 24/7. My daily consumption when cruising including anchor lights at night is around 70ah per day and usually I am minus around 35ah at daybreak. On a sunny day am back to positive by 10.00am. The panels will put in around 15 amps max. On our last 10 day cruise I did not have to run the motor once apart from getting in and out of the Marina, what quiet bliss!. Worst situation on another trip was three days of continuous rain and got to minus 120ah but was back to positive after two cloudy but not rainy days. Why anyone wants gensets or big alternators is beyond me.
Get a SolarStik
That's all.
Seriously, I think you will hear a lot of people talk about determining your needs first, which is a good idea. Then I think you will hear a lot of people echo 4 X Trojan T105 batteries, and a good solar charge controller with MPPT, and good panels. The SolarStik will even give you a place to mount a wind gen if you wish. Determine your needs first, and then move forward. I don't think we even know what kind of boat you have.
That's all.
Seriously, I think you will hear a lot of people talk about determining your needs first, which is a good idea. Then I think you will hear a lot of people echo 4 X Trojan T105 batteries, and a good solar charge controller with MPPT, and good panels. The SolarStik will even give you a place to mount a wind gen if you wish. Determine your needs first, and then move forward. I don't think we even know what kind of boat you have.
going off on a slight tangent...
I wonder if many folks here leave the dock with a portable power supply/jump starting battery. We recently picked one up for our car until my son went off to college and I gave it to him. He's actually used it once and it saved him when his battery had run down. Seems to make sense to me to have one aboard. Only about $50 +/- and some even come with a built in compressor.
I wonder if many folks here leave the dock with a portable power supply/jump starting battery. We recently picked one up for our car until my son went off to college and I gave it to him. He's actually used it once and it saved him when his battery had run down. Seems to make sense to me to have one aboard. Only about $50 +/- and some even come with a built in compressor.
Chet - Where in HdG
Chet, I'm also up in HdG and can tell you my experience. In my last boat, a hunter 29.5, I replaced the two wet cell Group 24s with two AGM Group 27s and as important, I replaced the stock charger with a 20 amp xantrex smart charger. Never had another problem on that boat after that and could spend a good 2 days at anchor although it didn't have many of the finer creature comforts like AC. On my new to me h356, the PO kept the 2 standard wet cell group 27s as the starter battery and added 4 6 volt golf carts batteries (Trojans 105s). I do have more toys and comforts on this boat so the extra 440 ah is much appreciated. It also has the xantrex 40 amp chrager, link 10 monitoring system but stil the stock alternator. I haven't really put these batteries to teh test yet since we only had teh boat in the water for about a month and a half last season.
Chet, I'm also up in HdG and can tell you my experience. In my last boat, a hunter 29.5, I replaced the two wet cell Group 24s with two AGM Group 27s and as important, I replaced the stock charger with a 20 amp xantrex smart charger. Never had another problem on that boat after that and could spend a good 2 days at anchor although it didn't have many of the finer creature comforts like AC. On my new to me h356, the PO kept the 2 standard wet cell group 27s as the starter battery and added 4 6 volt golf carts batteries (Trojans 105s). I do have more toys and comforts on this boat so the extra 440 ah is much appreciated. It also has the xantrex 40 amp chrager, link 10 monitoring system but stil the stock alternator. I haven't really put these batteries to teh test yet since we only had teh boat in the water for about a month and a half last season.
Always plenty of variables....
and all of the advice you are getting here is good, Chet. (The debate between dedicated starter battery and 2 banks of deep cycle is a good one - there are good arguments either way) I would add that the factors/equations required for cruising sailors are different than those for weekenders. When I shove off on Friday/Saturday, I know both my banks are 100% charged, whereas a cruiser will almost NEVER see more than 80-90%. Also, the '50% discharge level rule' that cruisers mostly adhere to isn't a big deal if you do overnight trips - even discharging down to 30%, a regular wet-cell will last several hundred discharge cycles. That matters if you are going through 365 cycles a year, but 20 or 30 cycles a year isn't going to kill your batteries anytime soon. If you really want to manage your batteries well, don't spend lots of money buying lots of expensive batteries, but DO buy 2 indespensible items: 1. Nigel Calder's book: Boatowners Mechanical and Electrical Manual... if there's a better book on the subject, somebody forgot to tell me. 2. A good battery monitor, like the Link 10/20. All this talk about bank size, consumption, charging away from shore power, alternative sources, etc., is just going to be theory, unless you actually KNOW what's happening to your batteries. So here's my 2c... shooting blind since I don't know much about your situation: 1. Sit down and calculate your expected draw. Spend some time at it - I'm going out for a weekend, so I need 2 nights x 12 hours x 1 amp(?) for my anchor light. My fridge draws 2 amps/hour x 24 hours x 2 days...... bet you buy a block of ice! 2. Once you have an idea how much you are going to consume, look at your sailing patterns and engine usage and see how much you can replenish while you're sailing. 3. Buy batteries (if your boat-bucks are AT ALL limited, skip the AGM/Gell. Put the money you save in the Link monitor I mentioned above) to meet your needs. Definitely do NOT buy gell cells unless you are also going to pony up big bucks for a smart alternator/regulator on your engine - gells are VERY sensitive to over charging, and they CANNOT be 'recovered' if they are cooked. 4. Don't buy lots more batteries than you need, unless you like lugging around hundreds of extra pounds and sailing slower. Hint: you can ALWAYS buy more batteries, but I doubt you'll find many sailors who voluntarily got rid of batteries. 5. If you're going to live-aboard a small boat on the hook down south, you're going to want solar panels, most likely. BUT! If you don't absolutely positively need them NOW, don't buy them now - solar panels are likely to get MUCH more efficient and less costly over the next few years as money flows into research. They've been getting better and cheaper for the past 20 years, and the progression is at least going to stay linear, if not better. Finally: on the starter/2 banks issue, I have 2 Gp29s in one bank and a legacy 8D in the other. With a Yanmar 2GM20F, either bank fires my engine no problem - I usually use both, then switch to the 29s, keeping the 8D (that sucker is 10 years old and still holds its own, and I'm dreading the day I have to hoist it out of the boat!). For backup, I have a WM 'Jump Start Elite', which will start the engine in an emergency, and power my running lights till dawn if I need them. It's isolated from the ENTIRE electrical system, so I know that it will be there if I need it. Highly unlikely, since batteries don't 'just die', but comforting. (I've got a hand-held VHF and a spare battery-powered GPS, as well) Well, there's my 2c. I'll bet Havre De Grace is a lot different than when i briefly lived in Aberdeen 25 years ago. Cheers, Bob s/v X SAIL R 8
and all of the advice you are getting here is good, Chet. (The debate between dedicated starter battery and 2 banks of deep cycle is a good one - there are good arguments either way
) I would add that the factors/equations required for cruising sailors are different than those for weekenders. When I shove off on Friday/Saturday, I know both my banks are 100% charged, whereas a cruiser will almost NEVER see more than 80-90%. Also, the '50% discharge level rule' that cruisers mostly adhere to isn't a big deal if you do overnight trips - even discharging down to 30%, a regular wet-cell will last several hundred discharge cycles. That matters if you are going through 365 cycles a year, but 20 or 30 cycles a year isn't going to kill your batteries anytime soon. If you really want to manage your batteries well, don't spend lots of money buying lots of expensive batteries, but DO buy 2 indespensible items: 1. Nigel Calder's book: Boatowners Mechanical and Electrical Manual... if there's a better book on the subject, somebody forgot to tell me. 2. A good battery monitor, like the Link 10/20. All this talk about bank size, consumption, charging away from shore power, alternative sources, etc., is just going to be theory, unless you actually KNOW what's happening to your batteries. So here's my 2c... shooting blind since I don't know much about your situation: 1. Sit down and calculate your expected draw. Spend some time at it - I'm going out for a weekend, so I need 2 nights x 12 hours x 1 amp(?) for my anchor light. My fridge draws 2 amps/hour x 24 hours x 2 days...... bet you buy a block of ice! 2. Once you have an idea how much you are going to consume, look at your sailing patterns and engine usage and see how much you can replenish while you're sailing. 3. Buy batteries (if your boat-bucks are AT ALL limited, skip the AGM/Gell. Put the money you save in the Link monitor I mentioned above) to meet your needs. Definitely do NOT buy gell cells unless you are also going to pony up big bucks for a smart alternator/regulator on your engine - gells are VERY sensitive to over charging, and they CANNOT be 'recovered' if they are cooked. 4. Don't buy lots more batteries than you need, unless you like lugging around hundreds of extra pounds and sailing slower. Hint: you can ALWAYS buy more batteries, but I doubt you'll find many sailors who voluntarily got rid of batteries. 5. If you're going to live-aboard a small boat on the hook down south, you're going to want solar panels, most likely. BUT! If you don't absolutely positively need them NOW, don't buy them now - solar panels are likely to get MUCH more efficient and less costly over the next few years as money flows into research. They've been getting better and cheaper for the past 20 years, and the progression is at least going to stay linear, if not better. Finally: on the starter/2 banks issue, I have 2 Gp29s in one bank and a legacy 8D in the other. With a Yanmar 2GM20F, either bank fires my engine no problem - I usually use both, then switch to the 29s, keeping the 8D (that sucker is 10 years old and still holds its own, and I'm dreading the day I have to hoist it out of the boat!). For backup, I have a WM 'Jump Start Elite', which will start the engine in an emergency, and power my running lights till dawn if I need them. It's isolated from the ENTIRE electrical system, so I know that it will be there if I need it. Highly unlikely, since batteries don't 'just die', but comforting. (I've got a hand-held VHF and a spare battery-powered GPS, as well) Well, there's my 2c. I'll bet Havre De Grace is a lot different than when i briefly lived in Aberdeen 25 years ago. Cheers, Bob s/v X SAIL R 8- Status