Let's forget about the "Perfect World" of battery power. We will be cruising the Chesapeake/L.I. Sound areas over the next several years, with a POSSIBLE trip "down south" to Florida. I currently have between 300-350 amp hours in 3 batteries (NOT INCLUDING the starting battery!). My altinator is the stock 70 or so watt output that came standard with the Legend 35.5. We plan to anchor out as much as we can. On the other hand, I'm not going to the Carribean where you would anchor for long periods of time and need a higher degree of self-sufficiency. In our situation, we would always be within easy access to a marina facility. IT SEEMS TO ME(!) that a wind generator is overkill for the kind of cruising I will be doing. I have found on previous 3 to 4 week cruises to Block, Mystic, etc., with a smaller boat and about 200 amp hours available, we were fine with just battery and engine power. I would turn the refrig. thermostat to a low setting, or completely off at night, and use block ice to supplement the 12 volt power. Do any of you feel that a flexable Solar Panel would be of any help, keeping in mind that my house bank batteries are wired together? Any suggestions/recommendations from those of you who have done, or are doing, what we plan over the next few years will be appreciated. Thanks to all in advance, Pat
- Status
Solar
Try a solar panel. If you want more power use a solid not a flex panel. If you check ebay they have some and always West or US. Defender will have the best prices but you will have to wait if you order from them.
Try a solar panel. If you want more power use a solid not a flex panel. If you check ebay they have some and always West or US. Defender will have the best prices but you will have to wait if you order from them.
Solar Flex Panel
I have a US-32 Solar Panel mounted to the top of my dodger. During the day it can power the VHF, Speed, depth, and mast wind instruments. Kind of (free) power. If not using any power it usually can put 10 amp hrs back into the batteries each day (depending on conditions and location of panel). A solid solar panel is better for power, but the flexible panel does not let shadows effect it as much. Any power going back in the system is a definite advantage. Weigh the odds and I think you will agree that solar power is a great source of clean, quiet power. I wish I was going!!
I have a US-32 Solar Panel mounted to the top of my dodger. During the day it can power the VHF, Speed, depth, and mast wind instruments. Kind of (free) power. If not using any power it usually can put 10 amp hrs back into the batteries each day (depending on conditions and location of panel). A solid solar panel is better for power, but the flexible panel does not let shadows effect it as much. Any power going back in the system is a definite advantage. Weigh the odds and I think you will agree that solar power is a great source of clean, quiet power. I wish I was going!!
solar electric, inc.
Here is a plug for what I think you will find are the very best prices on panels. Their name is Solar Electric Inc, in San Diego. I have an array of eight panels, flexible or glass depending on location and shading, etc, and these take care of everything, including refrigeration and watermaker. They are on the cabin-top, the dodger, a hard bimini over the helmsman's seat, and a collapsible bimini over the cockpit. The ones on this last bimini easily move down to the lifelines and act as weather cloths when the bimini comes down. I wouldn't be without them and I saved a LOT of money buying them where I did.
Here is a plug for what I think you will find are the very best prices on panels. Their name is Solar Electric Inc, in San Diego. I have an array of eight panels, flexible or glass depending on location and shading, etc, and these take care of everything, including refrigeration and watermaker. They are on the cabin-top, the dodger, a hard bimini over the helmsman's seat, and a collapsible bimini over the cockpit. The ones on this last bimini easily move down to the lifelines and act as weather cloths when the bimini comes down. I wouldn't be without them and I saved a LOT of money buying them where I did.
Wired together - Observation
I added 2 flexable solar panels to the top of my bimini for my cruise from Galveston to Baltimore. We sailed most of the way across the Gulf and around to Ft Lauderdale so the extra amps were nice to have. They are easy to remove so when the winds got above 30 knots I stowed them in the battery locker (Port cockpit locker) Observation - I read other posts and have seen battery installations where the batteries are 'wired' together. I feel each battery should have it's own disconnect switch to allow checking of each indivdual battery voltage and taking out a battery going south before it takes the others with it. By using 2 A/B switches ($20 each) you would have total control over your 3 batteries. It also prevents total discharge of all your house batteries at once by splitting them into 2 or 3 banks, giving you an emergency reserve. I have 4 group 27 with 3 A/B switches. 1 is used to connect the other 2 together. With the switches I set them up in 2 banks of 2 batteries. I only discharge 1 bank to 12.0 VDC and then switch and discharge to 12.0 VDC then start then engine and recharge to 12.6 in less than an hour with the stock 60 amp alternator. That way if the engine doesn't start I still have some amps left. By recharging before the batteries get below 12.0 they charge faster and live longer. It is also good for the loads like the frig and freezer. Each battery is also connected to a voltmeter via a 4 position switch so I can check voltages daily to see if one of the cells is going bad. ONE bad battery can ruin the whole bushel.
I added 2 flexable solar panels to the top of my bimini for my cruise from Galveston to Baltimore. We sailed most of the way across the Gulf and around to Ft Lauderdale so the extra amps were nice to have. They are easy to remove so when the winds got above 30 knots I stowed them in the battery locker (Port cockpit locker) Observation - I read other posts and have seen battery installations where the batteries are 'wired' together. I feel each battery should have it's own disconnect switch to allow checking of each indivdual battery voltage and taking out a battery going south before it takes the others with it. By using 2 A/B switches ($20 each) you would have total control over your 3 batteries. It also prevents total discharge of all your house batteries at once by splitting them into 2 or 3 banks, giving you an emergency reserve. I have 4 group 27 with 3 A/B switches. 1 is used to connect the other 2 together. With the switches I set them up in 2 banks of 2 batteries. I only discharge 1 bank to 12.0 VDC and then switch and discharge to 12.0 VDC then start then engine and recharge to 12.6 in less than an hour with the stock 60 amp alternator. That way if the engine doesn't start I still have some amps left. By recharging before the batteries get below 12.0 they charge faster and live longer. It is also good for the loads like the frig and freezer. Each battery is also connected to a voltmeter via a 4 position switch so I can check voltages daily to see if one of the cells is going bad. ONE bad battery can ruin the whole bushel.
I think you'd be fine with what you have...
I've done basically what you've done (excluding Fl trip). Most likely whereever you anchor, you'll be motoring out/in and motoring to some destinations so you'll be charging. Let's face it...on a 'cruise' really what % is sailing/motoring. If you go to Fl, via ICW, you'll do a lot of motoring. And if you sail, you will frequently stop at marinas. Gee....maybe a motor boat .....
I've done basically what you've done (excluding Fl trip). Most likely whereever you anchor, you'll be motoring out/in and motoring to some destinations so you'll be charging. Let's face it...on a 'cruise' really what % is sailing/motoring. If you go to Fl, via ICW, you'll do a lot of motoring. And if you sail, you will frequently stop at marinas. Gee....maybe a motor boat .....
Power suggestion
Feb.13,2001 Dear Pat, Bearing in mind that you will be spending long periods at anchor and assuming an even modest rate of power consumption of 50 amps/hours per day, and many cruisers record 80 to 120 amp/hrs per day, a single flex panel will not meet your domestic needs. It will however provide a nice trickle charge to keep the starter battery topped up. Keeping in mind that you don't want to go into overkill buy adding a lot of gear like a wind generator etc, what I would suggest that you might want to consider is this: (1) a flex solar panel for the starter battery to provide it with independent charging should the rest of the system fail, and (2) a smart regulator for the 70 amp alternator. Since most alternators never come close to putting out their rated amperage the smart three stage regulator will allow you to top up your batteries with maximum efficency and minimum diesel hours. With three group 27 batteries rated at 105 amps you have about 150 amps of available power until you are 50% discharged. Keep in mind that group 27 have an optimum discharge of about 31% which means that to optimize your batteries life span you would actually only want to be using about 50 amps a day with what you have. You could give the batteries the bulk load charge and intermediate charge with the engine running and run the refer at the same time. When the regulator kicks into trickle charge mode, assuming the refer is chilled down for the day, you could then switch the long trickle charge period to the solar panel, which is something it does best. I hope this suggestion is of the practical nature you were seeking. Fair winds, Brian Pickton of BeneteauOwners.net, aboard The Legend, Rodney bay St. Lucia
Feb.13,2001 Dear Pat, Bearing in mind that you will be spending long periods at anchor and assuming an even modest rate of power consumption of 50 amps/hours per day, and many cruisers record 80 to 120 amp/hrs per day, a single flex panel will not meet your domestic needs. It will however provide a nice trickle charge to keep the starter battery topped up. Keeping in mind that you don't want to go into overkill buy adding a lot of gear like a wind generator etc, what I would suggest that you might want to consider is this: (1) a flex solar panel for the starter battery to provide it with independent charging should the rest of the system fail, and (2) a smart regulator for the 70 amp alternator. Since most alternators never come close to putting out their rated amperage the smart three stage regulator will allow you to top up your batteries with maximum efficency and minimum diesel hours. With three group 27 batteries rated at 105 amps you have about 150 amps of available power until you are 50% discharged. Keep in mind that group 27 have an optimum discharge of about 31% which means that to optimize your batteries life span you would actually only want to be using about 50 amps a day with what you have. You could give the batteries the bulk load charge and intermediate charge with the engine running and run the refer at the same time. When the regulator kicks into trickle charge mode, assuming the refer is chilled down for the day, you could then switch the long trickle charge period to the solar panel, which is something it does best. I hope this suggestion is of the practical nature you were seeking. Fair winds, Brian Pickton of BeneteauOwners.net, aboard The Legend, Rodney bay St. Lucia
bigger alternator
I am not shure that your stock alternator is rated 70 amp , most probably 60 or 55. But with your batt cappacity , there is no way you will charge close to full the battery , with present configuration, I would suggest , if your alternator is in good order , along with all wiring , to have a smart multi stage regulator for it . However , there are opinions that such 'booster' regulator , might ,in practice, 'overwork' the regular stock alternator , which might shorten it's life span. Another better option, more costly, to have a more powerfull and heavy-duty marine alternator-for your demands a 100 amp one- with same smart multi stage regulator , which will be a much better-and less problematic on the long run.
I am not shure that your stock alternator is rated 70 amp , most probably 60 or 55. But with your batt cappacity , there is no way you will charge close to full the battery , with present configuration, I would suggest , if your alternator is in good order , along with all wiring , to have a smart multi stage regulator for it . However , there are opinions that such 'booster' regulator , might ,in practice, 'overwork' the regular stock alternator , which might shorten it's life span. Another better option, more costly, to have a more powerfull and heavy-duty marine alternator-for your demands a 100 amp one- with same smart multi stage regulator , which will be a much better-and less problematic on the long run.
Wow! Thanks to all for the info.
You have all been very helpful, for which I thank you. I have concluded that if I do nothing at all, and use my present resourses, along with an occassional night at a dock to charge up the system, I'll probably be fine. This is basically what I have been doing. The longest time spent pn the hook was three nights (with refrig. off). On the other hand I can increase my "away" time substantially by adding a smart regulator, solar charger, larger altinator, or some combination of the three. A wind generator is not needed! Mickey McHugh, thanks for the wiring suggestion. I have two selector switches now but configured differently then what you suggested. My starting battery is completely seperated from the house bank of 27's, but I am able to switch the entire house bank into the starting circuit. I will be installing a programable LINK 10 by Heart Interface into the system to help monitor the battery condition. I would appreciate hearing from you for other alternatives, or if you think that the present set up is inefficient. Once again, thanks to all, Pat
You have all been very helpful, for which I thank you. I have concluded that if I do nothing at all, and use my present resourses, along with an occassional night at a dock to charge up the system, I'll probably be fine. This is basically what I have been doing. The longest time spent pn the hook was three nights (with refrig. off). On the other hand I can increase my "away" time substantially by adding a smart regulator, solar charger, larger altinator, or some combination of the three. A wind generator is not needed! Mickey McHugh, thanks for the wiring suggestion. I have two selector switches now but configured differently then what you suggested. My starting battery is completely seperated from the house bank of 27's, but I am able to switch the entire house bank into the starting circuit. I will be installing a programable LINK 10 by Heart Interface into the system to help monitor the battery condition. I would appreciate hearing from you for other alternatives, or if you think that the present set up is inefficient. Once again, thanks to all, Pat
Follow up
Feb. 14, 2001 Hi Pat, Just to follow up the earlier comments we made, first let me say that I agree with Alex that a larger alternator with a smart regulator is the better choice. I didn't include that suggestion because you were trying not to go nuts on buying equipment and so I limited the suggestion to just the smart regulator. I have yet to see any evidence that a smart regulator "works" an alternator harder since the parts that "work" in an alternator are the brushes. The rest is basically capturing the effects of a magnetic field. Since a dumb regulator is designed to protect batteries it will not utilize all of the output available from the alternator. Rather it chokes it down to prevent overcharging and overheating the batteries. I can't think of why a regulator, which regulates how much output is sent to the batteries, not how much the alternator produces at a given R.P.M., would overwork the alternator, but perhaps one of the readers with actual electrical engineering expertise could help us out here, because I would certainly like to know more about this issue. Second, while everybody wires there house bank to start the engine be advised that your starter motor may not be be rated for the amount of electricity available from them, which can cause the motor to burn out. Check the starter motor rating which should be in the engine manual to make sure your not overpowering it with the battery bank switched to "all". If you are, then wire up your switches so that you only draw on one part of your house bank to start in an emergency situation. Fair winds, Brian Pickton of BeneteauOwners.net, aboard The Legend, Rodney Bay St. Lucia
Feb. 14, 2001 Hi Pat, Just to follow up the earlier comments we made, first let me say that I agree with Alex that a larger alternator with a smart regulator is the better choice. I didn't include that suggestion because you were trying not to go nuts on buying equipment and so I limited the suggestion to just the smart regulator. I have yet to see any evidence that a smart regulator "works" an alternator harder since the parts that "work" in an alternator are the brushes. The rest is basically capturing the effects of a magnetic field. Since a dumb regulator is designed to protect batteries it will not utilize all of the output available from the alternator. Rather it chokes it down to prevent overcharging and overheating the batteries. I can't think of why a regulator, which regulates how much output is sent to the batteries, not how much the alternator produces at a given R.P.M., would overwork the alternator, but perhaps one of the readers with actual electrical engineering expertise could help us out here, because I would certainly like to know more about this issue. Second, while everybody wires there house bank to start the engine be advised that your starter motor may not be be rated for the amount of electricity available from them, which can cause the motor to burn out. Check the starter motor rating which should be in the engine manual to make sure your not overpowering it with the battery bank switched to "all". If you are, then wire up your switches so that you only draw on one part of your house bank to start in an emergency situation. Fair winds, Brian Pickton of BeneteauOwners.net, aboard The Legend, Rodney Bay St. Lucia
DC electrics
I beleive a boat's basic electrical system should be sound and efficient before any additional charging components are installed. There are many excellent books on the subject of 12 volt power management available from stores such as "West Marine" and "Defender". Most production boats have electrical systems that are only suitable for short stays away from the dock whithout causing permanent damage(usually unknown to the user) to the batteries. If one wishes to have a boat that is self-sufficient over the long term. Several electrical modifications must be made. This discussion assumes a single house battery bank and a seperate start battery controlled by a, industry standard, four position battery switch. 1. Determine your total daily electrical requirement in amps. 2. Size the house battery bank using this formula as an absolute minimum. Daily amp usage x 2 + 22%. Round up. 3. Buy a "hot rated" alternater. (other alternators are not designed to be used with 4.) Min size- 25% of the size of your house battery bank. Then install a "Zap Stop" or field disconnect on the battery switch. 4. Buy a Marine regulator from any one of many manufactures such as Balmar(which is the one I have} Heart, or Ample power. 3. Rewire the charging system, using nothing smaller than 2 gage if your alternator is in the 100 to 120 range. (Larger if you go above 120) 4. Fuse the house bank according to ABYC requirements. (Found at West Marine} 5. Install a device such as the LInk 10 and never discharge your batteries more than 50%. Following the above in its entirety will truely set you free from dockside electricity, requireing only an hour and a half to two hours of engine running time per day. You will no longer have to carry block ice or turn the ref. thermostat down. Any additional devices such as solar panels, a wind generator, or water generator (all of which should be considered only after the basic electrical system hase been modified) will simply reduce your engine running time. Also, 6 volt batteries are more durable and can be discharged further( without dammage) than group 27 batteries. Use the above as a guide, but, by all means, seek the guidance of a qualified marine electrician before making any modifications. A.B.
I beleive a boat's basic electrical system should be sound and efficient before any additional charging components are installed. There are many excellent books on the subject of 12 volt power management available from stores such as "West Marine" and "Defender". Most production boats have electrical systems that are only suitable for short stays away from the dock whithout causing permanent damage(usually unknown to the user) to the batteries. If one wishes to have a boat that is self-sufficient over the long term. Several electrical modifications must be made. This discussion assumes a single house battery bank and a seperate start battery controlled by a, industry standard, four position battery switch. 1. Determine your total daily electrical requirement in amps. 2. Size the house battery bank using this formula as an absolute minimum. Daily amp usage x 2 + 22%. Round up. 3. Buy a "hot rated" alternater. (other alternators are not designed to be used with 4.) Min size- 25% of the size of your house battery bank. Then install a "Zap Stop" or field disconnect on the battery switch. 4. Buy a Marine regulator from any one of many manufactures such as Balmar(which is the one I have} Heart, or Ample power. 3. Rewire the charging system, using nothing smaller than 2 gage if your alternator is in the 100 to 120 range. (Larger if you go above 120) 4. Fuse the house bank according to ABYC requirements. (Found at West Marine} 5. Install a device such as the LInk 10 and never discharge your batteries more than 50%. Following the above in its entirety will truely set you free from dockside electricity, requireing only an hour and a half to two hours of engine running time per day. You will no longer have to carry block ice or turn the ref. thermostat down. Any additional devices such as solar panels, a wind generator, or water generator (all of which should be considered only after the basic electrical system hase been modified) will simply reduce your engine running time. Also, 6 volt batteries are more durable and can be discharged further( without dammage) than group 27 batteries. Use the above as a guide, but, by all means, seek the guidance of a qualified marine electrician before making any modifications. A.B.
Probably OK as is
As Al's post indicates, your first question is what do you need. If you are just running a couple lights for a couple hours, and the anchor light, your amp hour requirement may be in the low 20s and your 300 AH bank will last more than a week before you need to recharge at all. On the other hand, if you are running lots of lights, stereo, and fans, you can get into the 40 AH range. You're ok maybe 4-5 days without recharge. If you're talking refridgeration, now you're in the 80-100 AH range. Now you need a bigger alternator, solar and/or wind, and probably a bigger bank if you are planning on more than a day or two at a time.
As Al's post indicates, your first question is what do you need. If you are just running a couple lights for a couple hours, and the anchor light, your amp hour requirement may be in the low 20s and your 300 AH bank will last more than a week before you need to recharge at all. On the other hand, if you are running lots of lights, stereo, and fans, you can get into the 40 AH range. You're ok maybe 4-5 days without recharge. If you're talking refridgeration, now you're in the 80-100 AH range. Now you need a bigger alternator, solar and/or wind, and probably a bigger bank if you are planning on more than a day or two at a time.
Solar Electric and other thoughts
Solar Electric Inc. DOES have a website: www.solarelectricinc.com, not to be confused with solarelectric.com, a completely different company. My contacts which have always been excellent, have been with Mike #1 (I suppose there is another Mike), or Scott. Good luck. Two other points.....A smart regulator CAN fry an alternator, by causing it to put out a "full field" output for longer than it is capable of doing. The high output creates a lot of heat, which will damage the coating to the windings and other electrical components. You can usually smell them start to heat, before serious damage. One of the characteristics of the high-output alternators is that not only are they capable of high output, they are capable of sustaining it. Most alternators are not, although the Hitachis often found on Yanmars are pretty good this way. You will still have to disable the internal regulator however, and change the alternator from an "N" alternator to a "P", which is a simple wiring task for an alternator shop, or even yourself. Also, a note to Brian, your starter will never be adversely affected by a battery bank that is too large, as long as it is still a 12 volt system. The "pressure" of 12 volts is the same, but you will just have a larger reservoir to draw upon, which will actually minimize voltage drop. This helps, as you can burn up an electrical motor with too LOW a voltage. Of course, if the extra batteries are wired incorrectly in series so as to create a voltage higher than that of a twelve volt system, all bets are off!
Solar Electric Inc. DOES have a website: www.solarelectricinc.com, not to be confused with solarelectric.com, a completely different company. My contacts which have always been excellent, have been with Mike #1 (I suppose there is another Mike), or Scott. Good luck. Two other points.....A smart regulator CAN fry an alternator, by causing it to put out a "full field" output for longer than it is capable of doing. The high output creates a lot of heat, which will damage the coating to the windings and other electrical components. You can usually smell them start to heat, before serious damage. One of the characteristics of the high-output alternators is that not only are they capable of high output, they are capable of sustaining it. Most alternators are not, although the Hitachis often found on Yanmars are pretty good this way. You will still have to disable the internal regulator however, and change the alternator from an "N" alternator to a "P", which is a simple wiring task for an alternator shop, or even yourself. Also, a note to Brian, your starter will never be adversely affected by a battery bank that is too large, as long as it is still a 12 volt system. The "pressure" of 12 volts is the same, but you will just have a larger reservoir to draw upon, which will actually minimize voltage drop. This helps, as you can burn up an electrical motor with too LOW a voltage. Of course, if the extra batteries are wired incorrectly in series so as to create a voltage higher than that of a twelve volt system, all bets are off!
Uni-Solar USF-32 panel installation
This has been a great discussion. I have decided to purchase a Uni-Solar USF-32 flexible panel and install it on top of my bimini. I am trying to find out what if anything additional I will need to buy. (i.e. charge controller, fuses, low-loss Schottky diodes, etc.) I will be hooking the panel up to a two-battery (group-27's) system with a single battery switch. I would appreciate any information or experience anyone has with installing these panels. Also can the panel be hooked up to the batteries the same time the motor is running? Also, Solar Electric Inc. (www.solarelectricinc.com) has great prices on these panels. Please excuse my lack of knowledge on this stuff. John
This has been a great discussion. I have decided to purchase a Uni-Solar USF-32 flexible panel and install it on top of my bimini. I am trying to find out what if anything additional I will need to buy. (i.e. charge controller, fuses, low-loss Schottky diodes, etc.) I will be hooking the panel up to a two-battery (group-27's) system with a single battery switch. I would appreciate any information or experience anyone has with installing these panels. Also can the panel be hooked up to the batteries the same time the motor is running? Also, Solar Electric Inc. (www.solarelectricinc.com) has great prices on these panels. Please excuse my lack of knowledge on this stuff. John
Thanks to all. Very informative!!!
There has been a great deal of information offered as a result of my original question, most of it very informative, thought provoking and educational. Based upon this discussion, as well as further investigation of other sources, you may be interested in reading how I plan to solve the problem of replenishing the batteries while cruising. First, I feel I was correct with my initial assessment regarding wind generated power. It is "overkill" for the kind of cruising I will be doing. Second, I feel that the solar panel solution is very inefficient for the cost and the time/effort needed for installation. (Again, this is based on my proposed style of cruising - coastal) The solution which I feel is the most appropiate, efficient and cost effective is through the installation of a high output Balmar duel output alternator with the Balmar Regulator. The charging system cables would be upgrade to # 2 wire, and a Heart Interface Link 10 will be installed to monitor the house bank, which consists of approximately 300 amp hours to be eventually upgraded to 400. I have done sufficient short term cruising (2 - 4 weeks at a time) to realize that, as much as we all would like to sail all of the time, this is seldom possible. It's usually blowing from whatever direction you wish to go. At any rate, even with sailing a great deal of the time, the motor will be used frequently, if not every day. Use of the hi output alternator will allow the batteries to be sufficiently recharged to permit relatively unrestricted use of 12 volt power, including refrigeration without having to rely on the use of block ice for cooling. Once again I want to thank everyone who has contributed to this discussion. It only reinforces the value of HOW. PAT
There has been a great deal of information offered as a result of my original question, most of it very informative, thought provoking and educational. Based upon this discussion, as well as further investigation of other sources, you may be interested in reading how I plan to solve the problem of replenishing the batteries while cruising. First, I feel I was correct with my initial assessment regarding wind generated power. It is "overkill" for the kind of cruising I will be doing. Second, I feel that the solar panel solution is very inefficient for the cost and the time/effort needed for installation. (Again, this is based on my proposed style of cruising - coastal) The solution which I feel is the most appropiate, efficient and cost effective is through the installation of a high output Balmar duel output alternator with the Balmar Regulator. The charging system cables would be upgrade to # 2 wire, and a Heart Interface Link 10 will be installed to monitor the house bank, which consists of approximately 300 amp hours to be eventually upgraded to 400. I have done sufficient short term cruising (2 - 4 weeks at a time) to realize that, as much as we all would like to sail all of the time, this is seldom possible. It's usually blowing from whatever direction you wish to go. At any rate, even with sailing a great deal of the time, the motor will be used frequently, if not every day. Use of the hi output alternator will allow the batteries to be sufficiently recharged to permit relatively unrestricted use of 12 volt power, including refrigeration without having to rely on the use of block ice for cooling. Once again I want to thank everyone who has contributed to this discussion. It only reinforces the value of HOW. PAT
What about Wind
What about considering wind power. A great many of the boats in the marina I am in have wind generators. Some with solar as well. A generator that can be used in water (when running) seems to make the most sense. I plan on install both prior to a long trip next year.
What about considering wind power. A great many of the boats in the marina I am in have wind generators. Some with solar as well. A generator that can be used in water (when running) seems to make the most sense. I plan on install both prior to a long trip next year.
Wind Generators
A friend with refrigeration didn't have one and after his first cruise needed to run his engine 2 hours a day to keep the batteries charged. Since adding a wind generator never has to run his engine. Now for the bad news. They are so noisy that if I had one on my boat I guarantee you I would pull out my old out of date flares and shoot it off the back of my boat. very very noisy!!!!
A friend with refrigeration didn't have one and after his first cruise needed to run his engine 2 hours a day to keep the batteries charged. Since adding a wind generator never has to run his engine. Now for the bad news. They are so noisy that if I had one on my boat I guarantee you I would pull out my old out of date flares and shoot it off the back of my boat. very very noisy!!!!
Another thought
Although I am firmly in the Solar Camp, some of my full time cruising friends just buy a small gas generator, the biggest battery charger it will drive, and call it good. Not elegant, at all, but probably the most cost effective, particularly if your cruising plans are modest. Some of the smaller generators are pretty quiet, too.
Although I am firmly in the Solar Camp, some of my full time cruising friends just buy a small gas generator, the biggest battery charger it will drive, and call it good. Not elegant, at all, but probably the most cost effective, particularly if your cruising plans are modest. Some of the smaller generators are pretty quiet, too.
And sill another comment!!...
For a boat with refrigeration the comment by Al Budding is right on target - after all, this is how I've set up the system on our H-35 (of course I'm unbiased!) in order to support the refrigeration. We have two banks of golf carts for about 450 AH plus a start battery. This is driven by a Balmar 70 A alternator w/ three step charger and it works out fine. The 70 A Balmar puts out about 135 A when cold (if memory serves me correctly) per the bench test and decreases as it warms up which is just fine. Balmars are rated "hot". The Yanmar V-belt won't fit so you'll need a bigger one. The 100 A alternators really should have two belts to not pressure the pully too much. I had a Siemens M-75 which really helped but lost it overboard while moving it around to capture the sun. Square knots are not guarenteed. Really need two large pannels to support refrigeration power requirements. We also have a Honda 650 generator which we lug along on the remote trips but the DC output is pathetic - use the AC output and run it through through the inverter for better output. Also, the Honda doesn't like salt air so keep it covered with a plastic bag when not in use. Air power: We have a Rutland 6-blade and it's reasonably quiet. Noise: A lot depends on how it's mounted because the vibrations can telegraph down inside the boat. Our current setup which is easily removed, mounted on the stern rail and braced, is quiet. I only install this for the west coast of Vancouver Island and north of Chatham Point in Johnstone Strait. Output is great!! for our purposes. Solar is hard to beat inspite of the up-front cost. Running the engine to charge batteries is very expensive and causes a lot of wear and tear on the engine. If you sell the boat you should be able to take the solar panels off if you plan ahead with the mounting. Low voltage: This is VERY HARD on motors! Starting motor, refrigeration compressors, autopilots, forced air heaters, etc. Use large conductors and design for low voltage drop. Figure startup current at 3.5 x running current. Also corrosion builds resistance quickly so use all marine grade (tin plated) components.
For a boat with refrigeration the comment by Al Budding is right on target - after all, this is how I've set up the system on our H-35 (of course I'm unbiased!) in order to support the refrigeration. We have two banks of golf carts for about 450 AH plus a start battery. This is driven by a Balmar 70 A alternator w/ three step charger and it works out fine. The 70 A Balmar puts out about 135 A when cold (if memory serves me correctly) per the bench test and decreases as it warms up which is just fine. Balmars are rated "hot". The Yanmar V-belt won't fit so you'll need a bigger one. The 100 A alternators really should have two belts to not pressure the pully too much. I had a Siemens M-75 which really helped but lost it overboard while moving it around to capture the sun. Square knots are not guarenteed. Really need two large pannels to support refrigeration power requirements. We also have a Honda 650 generator which we lug along on the remote trips but the DC output is pathetic - use the AC output and run it through through the inverter for better output. Also, the Honda doesn't like salt air so keep it covered with a plastic bag when not in use. Air power: We have a Rutland 6-blade and it's reasonably quiet. Noise: A lot depends on how it's mounted because the vibrations can telegraph down inside the boat. Our current setup which is easily removed, mounted on the stern rail and braced, is quiet. I only install this for the west coast of Vancouver Island and north of Chatham Point in Johnstone Strait. Output is great!! for our purposes. Solar is hard to beat inspite of the up-front cost. Running the engine to charge batteries is very expensive and causes a lot of wear and tear on the engine. If you sell the boat you should be able to take the solar panels off if you plan ahead with the mounting. Low voltage: This is VERY HARD on motors! Starting motor, refrigeration compressors, autopilots, forced air heaters, etc. Use large conductors and design for low voltage drop. Figure startup current at 3.5 x running current. Also corrosion builds resistance quickly so use all marine grade (tin plated) components.
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