I'm looking for a solar panel to charge my battery on my H-26. Is there one out ther for under 100$. Will a five watt charger do a sufficent charge?
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Used a 5 watt solar panel for 15 years
Hi, We bought a Clipper Marine 26 in 1985. The first winter we had it, we installed a 5 watt solar panel just in front of the mast step and wired it to the battery directly with a diode. We started every season with a charged battery and never had to recharge during the Lake Michigan sailing season (May to November). We had an old Honda outboard without the charger capability. We paid over $150 for ours but I have seen 5 watt panels in places like Harbor Freight for under $40. Be sure to test it at deck angle to see how much you get. We only used battery power for our running lights so you will have to do a power-use inventory to determine if 5 watts is enough for you. We sold our Clipper Marine in 2000 and the solar panel was still going strong. It was an Arco brand panel. We replaced our battery twice in that time. Good luck.
Hi, We bought a Clipper Marine 26 in 1985. The first winter we had it, we installed a 5 watt solar panel just in front of the mast step and wired it to the battery directly with a diode. We started every season with a charged battery and never had to recharge during the Lake Michigan sailing season (May to November). We had an old Honda outboard without the charger capability. We paid over $150 for ours but I have seen 5 watt panels in places like Harbor Freight for under $40. Be sure to test it at deck angle to see how much you get. We only used battery power for our running lights so you will have to do a power-use inventory to determine if 5 watts is enough for you. We sold our Clipper Marine in 2000 and the solar panel was still going strong. It was an Arco brand panel. We replaced our battery twice in that time. Good luck.
Go thru some calculations John
There was a good thread on this just last week. In summary: Go thru all your loads, determine capacites, determine charge time, and calculate it up. Only you can determine what size solar system will be adequate based on your loads,capacity,and charge duration. If you want some help, post some numbers and help will follow. FYI - If you use a 5W panel and it charges up for the day, you will have stored 50 Watt Hours of energy. You'll barely have enough charge to last an hour or two for all your running lights(unless you use LED's). Something to chew on...
There was a good thread on this just last week. In summary: Go thru all your loads, determine capacites, determine charge time, and calculate it up. Only you can determine what size solar system will be adequate based on your loads,capacity,and charge duration. If you want some help, post some numbers and help will follow. FYI - If you use a 5W panel and it charges up for the day, you will have stored 50 Watt Hours of energy. You'll barely have enough charge to last an hour or two for all your running lights(unless you use LED's). Something to chew on...
Not totally true Landsend..
A blanket statement like that without knowing all parameters is not true. I agree that 5W is small(flea power to me) but it may be enough for what he needs. Besides, if he could get away with 5W, he could save some deck space. On a 26 ft. boat this would be highly desirable. Hate to disagree but... John needs to be informed. John, you really need to post some numbers for us - we will help.
A blanket statement like that without knowing all parameters is not true. I agree that 5W is small(flea power to me) but it may be enough for what he needs. Besides, if he could get away with 5W, he could save some deck space. On a 26 ft. boat this would be highly desirable. Hate to disagree but... John needs to be informed. John, you really need to post some numbers for us - we will help.
I think what GuyT is trying to say...
...is that the 5 watt charger won't run your fridge. It will, however, trickle charge a battery with minimal stress to the battery. You actually want the SMALLEST charger that can do the job. All you've got to do is figure out, in amp hours, how big the job is.
...is that the 5 watt charger won't run your fridge. It will, however, trickle charge a battery with minimal stress to the battery. You actually want the SMALLEST charger that can do the job. All you've got to do is figure out, in amp hours, how big the job is.
Hey Guys and Gals
Will a five watt charger do a fair job of keeping me powered if I sail one day a week and also charge with my Honda OB(9.9) Rare use of nav lights, frequent stereo use, and occassional fan and cabin lights? Or do I need to charge with a battery charger on a frequent basis...A new battery is approx 50$ and I would like to get at least a couple of years out it
Will a five watt charger do a fair job of keeping me powered if I sail one day a week and also charge with my Honda OB(9.9) Rare use of nav lights, frequent stereo use, and occassional fan and cabin lights? Or do I need to charge with a battery charger on a frequent basis...A new battery is approx 50$ and I would like to get at least a couple of years out it
john w.
John, think about it this way: a typical $50 battery such as a Delco Voyager is rated at 115 amp hours, which means you have 57 usable amp hours before needing to recharge, at least when the battery is new. Lets assume that you never draw it down more than 60 amp hours during a weekend (otherwise, I'm assuming, you'd have replaced it with a larger battery bank by this time.) A five-watt solar charger will give you, conservatively, 40 amp hours of charge every day during the summer months. That means that from Monday through Friday the charger will pump 200 amp hours back into the battery. Thats more than three times what you took out over the weekend. A larger charger will just cook the battery earlier. The guy with the fifteen-amp solar charger will be scratching his head wondering why he has to purchase a new battery every year, while you're getting three to four years out of every battery because you were smart enough not to overpower it.
John, think about it this way: a typical $50 battery such as a Delco Voyager is rated at 115 amp hours, which means you have 57 usable amp hours before needing to recharge, at least when the battery is new. Lets assume that you never draw it down more than 60 amp hours during a weekend (otherwise, I'm assuming, you'd have replaced it with a larger battery bank by this time.) A five-watt solar charger will give you, conservatively, 40 amp hours of charge every day during the summer months. That means that from Monday through Friday the charger will pump 200 amp hours back into the battery. Thats more than three times what you took out over the weekend. A larger charger will just cook the battery earlier. The guy with the fifteen-amp solar charger will be scratching his head wondering why he has to purchase a new battery every year, while you're getting three to four years out of every battery because you were smart enough not to overpower it.
Use two batteries John !
I would keep one battery on the engine and let the alternator from the engine charge up that one. If you go out there once a week, this will be no problem. If you use all your power up while on the boat and need to start the engine, you may not be able to because of your low state of charge. Also - you must know if it is a 5 watt solar or a 5 amp solar. I used a 5 Watt solar. A 5 Watt solar is comparable to a 0.4 Amp solar. Big difference between the two! Also make sure that you have a solar charge controller that prevents overcharge of the batteries - these are pretty standard these days. Now lets talk about your "House" power budget. First lets make some assumptions that you will be on the boat for 6 hours once a week - if it is more or less, you can adjust your numbers. Look at the max power from each device - your devices will be different than this example. You need to plug in your numbers! Stereo = 20Watts x 6 Hours = 120 WattHours Fan = 15W x 6 Hours = 90 WattHours Running Lights = 50W x 2 Hours = 100 WattHours Total Watt Hours = 120+90+100 = 310 WattHours If you have a 5 Watt solar panel and lets say you get on average 40 Watt Hours per day, you will accumulate 40 WattHours x 7 Days = 280 Watt Hours cummulative charge. So, in this example you will not have enough from a 5 W solar panel. You always want to have a surplus of charge because of the battery charge acceptance and the efficiency loss. Try to have at least 20 percent more charge capacity than discharge. This way you always fully charge that battery! From this crude calculation, it looks like you will need at battery that has at least 620 Watt Hours of capacity(total WattHour required x 2) or in AmpHours = 620W/11.1VDC = 56 AmpHours. So, in my estimation I would get at least a 60 Amp Hour battery for your house requirements(Group 24) with a 10 Watt solar cell. I would also get a small wet battery for your engine and just let your motor charge this up. Now, plug your numbers in and see what you get!
I would keep one battery on the engine and let the alternator from the engine charge up that one. If you go out there once a week, this will be no problem. If you use all your power up while on the boat and need to start the engine, you may not be able to because of your low state of charge. Also - you must know if it is a 5 watt solar or a 5 amp solar. I used a 5 Watt solar. A 5 Watt solar is comparable to a 0.4 Amp solar. Big difference between the two! Also make sure that you have a solar charge controller that prevents overcharge of the batteries - these are pretty standard these days. Now lets talk about your "House" power budget. First lets make some assumptions that you will be on the boat for 6 hours once a week - if it is more or less, you can adjust your numbers. Look at the max power from each device - your devices will be different than this example. You need to plug in your numbers! Stereo = 20Watts x 6 Hours = 120 WattHours Fan = 15W x 6 Hours = 90 WattHours Running Lights = 50W x 2 Hours = 100 WattHours Total Watt Hours = 120+90+100 = 310 WattHours If you have a 5 Watt solar panel and lets say you get on average 40 Watt Hours per day, you will accumulate 40 WattHours x 7 Days = 280 Watt Hours cummulative charge. So, in this example you will not have enough from a 5 W solar panel. You always want to have a surplus of charge because of the battery charge acceptance and the efficiency loss. Try to have at least 20 percent more charge capacity than discharge. This way you always fully charge that battery! From this crude calculation, it looks like you will need at battery that has at least 620 Watt Hours of capacity(total WattHour required x 2) or in AmpHours = 620W/11.1VDC = 56 AmpHours. So, in my estimation I would get at least a 60 Amp Hour battery for your house requirements(Group 24) with a 10 Watt solar cell. I would also get a small wet battery for your engine and just let your motor charge this up. Now, plug your numbers in and see what you get!
You guys are being optimistic
about the output of a solar panel. Getting 50 watt/hours per day out of a 5 watt panel and into your batteries assumes: 1 full direct sun all day long 2 panel perpendicular to the suns rays all day long 3 no cloud cover all day long 4 10 hours of sun per day 5 100% charge effeciency from your battery If the above is true with a 12 volt system you will get about 4.16 amp/hours of current per day. As we all know, it is not a perfect world. Assume 40 - 50% of the above to be realistic.
about the output of a solar panel. Getting 50 watt/hours per day out of a 5 watt panel and into your batteries assumes: 1 full direct sun all day long 2 panel perpendicular to the suns rays all day long 3 no cloud cover all day long 4 10 hours of sun per day 5 100% charge effeciency from your battery If the above is true with a 12 volt system you will get about 4.16 amp/hours of current per day. As we all know, it is not a perfect world. Assume 40 - 50% of the above to be realistic.
Thanks Fred.
Sorry about the confusion. It's the last day of classes for the school year, the book order for the class I'm teaching in England this summer hasn't shown up yet, and a $36,000 grant still hasn't been posted to my budget despite it being the end of the fiscal year. Easier to delete the post than to fix it at this point.
Sorry about the confusion. It's the last day of classes for the school year, the book order for the class I'm teaching in England this summer hasn't shown up yet, and a $36,000 grant still hasn't been posted to my budget despite it being the end of the fiscal year. Easier to delete the post than to fix it at this point.
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