Thanks!
The cabin is spacious for a 27 footer, although I wish she was a heavier displacement, 5k lbs is a little light for the waters around here.... I'm starting to get a case of 10 footitis
Solar Charging Systems
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The cabin is spacious for a 27 footer, although I wish she was a heavier displacement, 5k lbs is a little light for the waters around here.... I'm starting to get a case of 10 footitis
From my own experience and setup: I have 50W flexible solar panel mounted on deck with MPPT controller. We use electricity very often on the boat, ie, radio, heating, cabin lights, running water, depth finder, inverter etc. We usually arrive Friday mid-day and leave Monday mornings. Upon return following Friday, batteries (2x135Ah) are fully charged (+13.8V). We start having sunlight deficit starting late August and from that point forth, until the boat is pulled out of the water early to mid October, we slowly loose charge but never below +12V.
Cool. I found a 12 watt mono crystalline panel on Amazon that's about 15 by 12 inches. I could probably mount it on the front hatch, lol.
I tied the power cord around the post the outlet is mounted on. It didnt come unplugged by itself, someone unplugged it for me. So rather than make it more secure or fuss with it, and rather than taking a chance on going up and finding the boat dead, having the boat maintain itself autonomously would be a better choice. It will pay for itself the first time I find the boat fully charged and ready to go.
There is another bonus many people get to take advantage of (including myself) to having the boat recharge itself, you can skip paying for shore power at the marina, that's a $300/yr savings.
My solar install paid for it's self in 1.5 years, not counting the longer battery life that I'll get. I'm almost $200 ahead on that investment already!
My solar install paid for it's self in 1.5 years, not counting the longer battery life that I'll get. I'm almost $200 ahead on that investment already!
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Someone check my math?
A 12 volt, 26 watt bulb (average 1156 automotive lamp) draws 2.16 amps? If the light was on for 12 hours, it would draw 25.92 AH?
A 12 watt solar panel would deliver 1 amp at most, so would take over 50 hours to restore the battery back to full power, plus efficiency losses. Is this correct?
And the charge controller would "maintain" the battery at full voltage indefinitely?
Are there any charge controllers to avoid? Sunforce any good??
A 12 volt, 26 watt bulb (average 1156 automotive lamp) draws 2.16 amps? If the light was on for 12 hours, it would draw 25.92 AH?
A 12 watt solar panel would deliver 1 amp at most, so would take over 50 hours to restore the battery back to full power, plus efficiency losses. Is this correct?
And the charge controller would "maintain" the battery at full voltage indefinitely?
Are there any charge controllers to avoid? Sunforce any good??
Thats what im thinking, one dead battery is $100 by itself, not counting the hassle.
About 50 hours yes....Also consider you only get about 5 "good" hours of direct sunlight per day on a stationary panel....so a good 10 days to recharge that 50 amp/hr deficit...
I choose to err on the high side of the equation with an 80 watt Bosch panel...so 5 ish amp on a good day X 5 hrs =25 amp/hr x 5 days (Mon-Fri) so I should be getting 125 a/hr or so return...Friday is a short day so loose a little there..
I have 2 admittly used and abused 120 amp batteries and have slipped into the 10v-11v range more than I care to admit on an "average" weekend use...
New batteries are on program for this coming season so that should help with storage capacity and keep me over the 50% discharge mark, but I'm pretty sure I'm not overpaneled by any means ...
I am always very conservative with power so the one battery will likely suffice. Obviously we need nav lights when under way at night, and steam light, but if the two are separate, the steam light will be the greatest drain if were anchored somewhere for an overnight. Cabin lights only intermittent, as too depth and knot meter, etc..
Currently I have an analog voltage meter. I would guess a digital would be more accurate?
Currently I have an analog voltage meter. I would guess a digital would be more accurate?
Not if the bulb is replaced with LED bulb which are readily available from marine retailers or on eBay.
LED's do use less power, but are they reliable, long lasting? Seems Ive read a bit about shorter life??
I cant climb the mast and taking it down to change bulbs repeatedly would get old real fast.
I cant climb the mast and taking it down to change bulbs repeatedly would get old real fast.
LED bulbs have theoretical life span of 25,000 hrs vs about 2000 hrs for incandescent lights (source: http://en.wikipedia.org/wiki/LED_lamp), so they do last much longer. I have replaced all my lights 2 years ago with LEDs (except for red and green nav lamp - colours were off with LED). After two seasons, not one failed and these were inexpensive bulbs off ebay. I have used "warm white" for the interior and "cool white" outside, I am very happy with the purchase.
yes, avoid sunforce!
genasun makes the best controller for the price, Morningstar are also good, but more expensive (although some have more options to justify that price)
with a good MPPT controller, depending on the panel voltage, that's roughly what you should see at peak output, maybe even a touch more if the panel is running a little high on the voltage.
We set up solar about 18 months ago and basically went w/ the largest panels available that would fit, without any math. We are full time liveaboards and we never use marinas.
We average 65 amps of 12 volts from the solar a day and the system is pretty much trickle charging by noon. I believe if we had a 12 volt fridge we'd use the system more efficiently.
So all this works great if we don't have a few overcast days with higher than normal use; like watching a movie or two on a dreary day.
If we deplete the battery bank a bit too much, then we play hell trying to build it back up because all our chargers (solar/engine/generator) reduce charging as the batteries come up.
Oh for a set of LiFePO4 batteries!
Obviously this whole bit is a moot point if you go back to a slip with power once in a while, but I thought I'd put it out there for those not intending to be tied to the dock and considering solar.
I love the solar and any problems I have w/ it is from my own power mismanagement, not the system.
I believe that with a high quality windgen and the solar we could move on to 12 volt refrigeration and be just fine. And more batteries; "MORE POWER", like Tim the tool man Taylor says. We'll see.
We average 65 amps of 12 volts from the solar a day and the system is pretty much trickle charging by noon. I believe if we had a 12 volt fridge we'd use the system more efficiently.
So all this works great if we don't have a few overcast days with higher than normal use; like watching a movie or two on a dreary day.
If we deplete the battery bank a bit too much, then we play hell trying to build it back up because all our chargers (solar/engine/generator) reduce charging as the batteries come up.
Oh for a set of LiFePO4 batteries!
Obviously this whole bit is a moot point if you go back to a slip with power once in a while, but I thought I'd put it out there for those not intending to be tied to the dock and considering solar.
I love the solar and any problems I have w/ it is from my own power mismanagement, not the system.
I believe that with a high quality windgen and the solar we could move on to 12 volt refrigeration and be just fine. And more batteries; "MORE POWER", like Tim the tool man Taylor says. We'll see.
I followed mainsails guide to small boat systems and it just works 365 even with the boat home in my driveway
Rather than go BIG the idea is to be really efficient Not take up deck space and minimize shading issues
At home in the winter with a nice southern exposure
The Gennasun puts out power at the crack of dawn and perks at 2.5 amps at high noon with a 40 watt panel
A bluesea cable-clam for NO leaks
And it does Not interfere with the swim ladder or any boat function and does a good job on TWO group 27 battery's
Of course my boats focus in on being very efficent
By using items like Sensabulbs which draw a fraction of the electricity
Rather than go BIG the idea is to be really efficient Not take up deck space and minimize shading issues
At home in the winter with a nice southern exposure
The Gennasun puts out power at the crack of dawn and perks at 2.5 amps at high noon with a 40 watt panel
A bluesea cable-clam for NO leaks
And it does Not interfere with the swim ladder or any boat function and does a good job on TWO group 27 battery's
Of course my boats focus in on being very efficent
By using items like Sensabulbs which draw a fraction of the electricity
The lights you replaced, did you replace the entire lamp assy, or just installed an led lamp that fits a standard socket, e.g, 1156, 3156, etc...
Guys,
Feel free to take a read of this. It may answer your questions.
Installing A Small Marine Solar System
Feel free to take a read of this. It may answer your questions.
Installing A Small Marine Solar System
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