Questions about solar chargers

[AXEL]

I'm thinking of adding a solar battery charging system to my C30. I know pretty much nothing about these systems. Defender has this system (Eco Series 20 watt). It looks good to me, affordable. Those of you who have experience, is this worth it? Will it charge my 2 batteries?

http://www.defender.com/product3.js...0-watt&path=-1|328|2290044|2290049&id=2708256

 

[Stu Jackson]

You could start here:

http://www.pbase.com/mainecruising/solar_panel

 

[AXEL]

I took a look at pbase site. One of the companies he recommended was eMarine. This system looks good.
https://www.emarineinc.com/20w-solar-charger-kit

 

[Chief RA]

AXEL: I would go up to the 80w kit if I were buying. Will recharge bank about 4x faster. Chief

 

[AXEL]

Thx Chief. I have a call into eMarine, waiting for them to call back.

 

[Chief RA]

AXEL: might want to check out Amazon as well. Chief

 

[Ned Ludd]

20 watts will be a maintenance level charge of about 1.2 amps. Determine your load and battery discharge rate then size the solar array accordingly for how long you can wait for a fully charged battery again.

 

[jeepbluetj]

What Ned said. You need to better define "charge up my batteries" in terms of depth of discharge and expected length of recharge. A 20W panel really is for maintenance, not any significant charging.

Also, anything non-marine will be much less expensive (same stuff, too). You'll need to figure out mounting.

I have a single 160w panel mounted on my stern rail. It'll allow me to be 'off the grid' for 4 or so days if I turn the fridge off at night.

 

[Chief RA]

JE: Yes, if we are advising full use and recharge, I would buy 200w panels. He may want to calculate draw though and hit it closer. Check the "inverter post" that is active now as well. Chief

 

[viper]

H380

20 watts will maintain, not really charge much.... The new solar panel deck charger for Hunters starter battery sold here is 30 watts.

I installed a 2nd bank of deep cycle bats in addition to my starter bat and D large house bat.

My plan is for over 400 watts, just could not fit more than 160 watt panel on davit. Will but 2-3 more over Bimini top.

Make sure the panels are monocrystalline NOT polly. With mono sun angle is less important and they generate power in much lower light levels. My 160 watt panels off of EBAY, American made, heavy duty frame cost $160 each. A 50 watt regulator cost 50 bucks.

You should be looking at a min of 100 watts.... Noting that measurement is at high noon on a very sunny day. In reality you need 2.5 times more watts than you calculate....

There are 300 watt panels slightly larger than my 160 watt now for about $160 or less....There are also Flex 100 watt panels for 150 bucks, that can be attached to a Bimini via crommets .. fit under a mattress and weigh just 4 lbs versus 26 lbs with an aluminum frame..... Could be also tied down to deck at anchor and plugged in...

I will add a Breeze X wind turbine to my mix (1600 installed).. still a lot cheaper altogether than installing a diesel generator for 12K, and then I still only have a 30 gallon diesel tank..

My backup Westinghouse 2500 watt gas gen, same size has a 2000 watt Honda/Yamaha arrives tomorrow at a cost of $579. This for an emergency...

Just as quiet, more fuel efficient, fair chance it will power 16,000 BTU a/c., comes with hours of op , total hours, fuel meter also that they don't come with.

Regards,

Viper

 

[AXEL]

I don't have a fridge. Just lights, small DC fans (sometimes), mast light, starting, auto pilot, etc. I am not sure about how to calculate usage/drain. I followed Stu's advice and looked up pbase. He has lots of good info and I have followed his advice before. I looked up his recommended list of suppliers and eMarine was the only one that supplied smaller complete (turn key) systems. I was hopping the less expensive 20 watt system would work but now I'm wondering. Still waiting for eMarine to call back.

 

[AXEL]

All very good info, thanks much to all. I finally got a call back from eMarine. Very nice people located in SE Fla. It sounds like I need to maximize my decision on wattage based on the practicality of where I can locate the panel. A 25" panel vs 60" panel and so on. My usage is minimal, but I would like to keep the batteries topped off and leave some extra for future upgrades. eMarine said what ever my decision they would config a complete package. Time to think it over ($$$).

 

[Ned Ludd]

I'll chime in again...I have (2) 125 amp hour batteries I use for starting and house batts. All of my lighting is LED, I run a 50 watt stereo and start my low compression Atomic 4 gas engine, just a knot meter and depth sounder for electronics. I sail on Tuesday night beer cans and overnight on weekends 2x per month over the summer. Our marina has no shore power. I have a 55 watt panel mounted on a stern post aimed for best sun from noon - 3 pm here in the Pacific North West and I always have a full charge when arriving at the boat.
If you can take a hydrometer reading of your batteries at full charge and then again after a typical discharge cycle, this can be calculated to an actual % of usage to gain insight into how much you need to recharge and how fast. Battery refractometers are fairly inexpensive now.

Conservation is cheaper than generation...

 

[AXEL]

I'll chime in again...I have (2) 125 amp hour batteries I use for starting and house batts. All of my lighting is LED, I run a 50 watt stereo and start my low compression Atomic 4 gas engine, just a knot meter and depth sounder for electronics. I sail on Tuesday night beer cans and overnight on weekends 2x per month over the summer. Our marina has no shore power. I have a 55 watt panel mounted on a stern post aimed for best sun from noon - 3 pm here in the Pacific North West and I always have a full charge when arriving at the boat.
If you can take a hydrometer reading of your batteries at full charge and then again after a typical discharge cycle, this can be calculated to an actual % of usage to gain insight into how much you need to recharge and how fast. Battery refractometers are fairly inexpensive now.

Conservation is cheaper than generation...

Ned,
Any chance you could send a photo of the mounted panel? Your info is helpful. I am now at the point of trying to figure how and where to mount a panel.
Thx
Thx

 

[viper]

The cost of the solar panels and regulators are now so cheap as compared to just a few years ago. The cost is your time to install and any mounting hardware... The cost of mounting a larger panel or smaller one is about the same in labor and material.

Regards,

Viper

 

[Ned Ludd]

I have an overkill piece of 1.25" SS pipe clamped to my stern rail currently. Used a 6" piece of 1.5" SS pipe tapped for (2) 1/4 x 20 bolts as the mounting head so it can pivot laterally then made the panel mount out of aluminum angle iron, through bolted through the 1.5" pipe so it can pivot vertically & it acts as a stop for the mounting head. This has stood up to 50 mph winds. For reference I can stand under the bimini and I am 6'1", I like the panel up high so I don't knock my head on it. This winter I will move the mount to the port transom corner where I had it on my last boat, that will drop the panel height about 18". I hope this gives you a good starting point.

 

[AXEL]

Interesting....do you leave it up all the time, even while sailing?

 

[Ned Ludd]

Yes it is up all the time

 

[Chief RA]

Ned: A 55w panel is probably fine for your limited use but for many of us who stay on our boats for extended days that is completely inadequate. Thats more like a day sailer concept and thats fine if thats what "blows your skirt up". Chief

 

[Ned Ludd]

That was my whole point, figure out what YOU need