Old Kyocera solar panels

[healhustler]

The previous owner of my boat spent 4 months each year in the Abacos, and set the boat up pretty well for being independent in anchorages. As part of the setup, he had two Kyocera KC 85T (85 watt) panels for charging batteries. After moving all the electronic equipment elsewhere, I easily have the space for 10 or more of these 40 X 25" panels. Would you use them, or buy more efficient panels. Even with 10 of these, I'd still only have 850 watts.

 

[CPseudonym]

Larry this is something I have researched a bit. Depending upon who you listen to mixing panels is ok. If you're at all like me, my nature is to recycle what I already have to control cost as you "already" have them.

However in this case I would lean heavily in favor of selling the two panels and purchase new ones as you've gone to the trouble of clearing the slate. May as well go the rest of the way maximizing output and efficiency.

 

[FlyWright]

I read elsewhere on the site that PV panels are running about $1 per watt. Replacing them with more modern, matching and perhaps more efficient panels might not be a very expensive option.

 

[healhustler]

Yeah, I guess you're right. I see that these panels are still available from several sources, but I was already thinking that maybe I should start from scratch. The later model panels are lighter and more productive. These panels are "trucks".....durable and heavy. Ultimately, I'd like to be able to power my fridge, pumps, lights and charge my batteries in the sun of Florida and the Bahamas, cutting way down on generator use.

 

[Brooksie]

Just paid $1 / watt for SunSense 245w panel and $200 for Morningstar MPPT controller. Not much use here on foggy Cape Cod but I am interested to try it.

 

[Carolena]

FYI - if you are looking for panels, check this supplier: Solar Cell, Solar Panel, Renewable Energy, Wind Energy, Charge Controller, Solar Trackers

I have not bought from them, yet, but have read good things about the company. I signed up for their specials and get one email every couple of weeks. On ocassion, I've seen name brand panels for well under $1 per watt. We were going to put some on the sailboat, but since we are selling her, it doesn't make sense. Thinking about a couple for our pilot house roof on the Tug.

 

[healhustler]

At a buck per watt, I may as well put the max coverage on my roof. So far, the solar I've had on the boat has really been like free juice. My Admiral and I dislike running the genset. As it is, I'm spending big bucks on a new hatch in the veranda to move the genset farther from our living area.

 

[portager]

I'd keep the old solar panels and call it a day. I wouldn't add any additional panels unless you need more watt hours to reliably complete float charge (see below).

When estimating solar panel performance you should keep in mind that manufacturer ratings are a best case number. Their ratings are the power that a solar panel could produce at the beginning of life under ideal conditions, i.e at noon at the equator with clear skies, the panel perpendicular to the sun and perfectly clean. This should be the guaranteed never to exceed number. As the angle of incidence changes the power output will drop due the reduction in the projected area from the suns view point and also due to increased losses due to reflection. You will also see a reduction due to cloud cover (which is why Florida isn't as good of a location for solar panels as Arizona).

Here are a couple of very interesting unbiased links on solar power:
Low-tech Magazine: The ugly side of solar panels
Energy Analysis of Power Systems: World Nuclear Association

I have never considered solar as a very good means of charging a battery bank. Once the battery bank is partially discharged the sulfates will start to crystallize which makes them harder to return to solution. For maximum battery life you want to recharge your battery bank as soon as possible. It isn't a good idea to sit around all day waiting for the sun to do it. Also, for maximum battery life you want to make sure that you full complete the float charge cycle to minimize sulfate build-up. If the day turns cloudy and you don't complete float charge your reducing the life of your batteries. I think the best use of solar is float charging. When you get up you run the generator to perform bulk charge and make hot water. Once bulk charge is complete you shut off the noise maker and let the solar panels complete float charge. This reduces generator run time. In my mine the ideal solar panel area is large enough to reliably complete float most of the time.

Also, if you buy new solar panels, make sure they are warrantied for a boat environment. Many manufacturers warranties are for stationary installations and are void in a dynamic environment.

 

[CPseudonym]

...make sure they are warrantied for a boat environment. Many manufacturers warranties are for stationary installations and are void in a dynamic environment.

It would be interesting to know how many folks have ever needed warranty repair of a solar panel. Far more likely for a dead panel out of the shipping box than 1 to 15 years later is my guess inasmuch as they lack moving parts.

 

[FF]

"Once the battery bank is partially discharged the sulfates will start to crystallize which makes them harder to return to solution. For maximum battery life you want to recharge your battery bank as soon as possible."

Textbook true , but so what?

Most boaters on the hook will either wait for 50% SOC or till the boat moves to charge the house set.

Even if the solar is only 100W it will still provide charge to raise the batt set charge level.

ONLY solar , or the power pole will regularly bring back house bank to 100% SCO as any other method takes hours and hours after 80-85%SOC is had,

For sitting out of service boats , solar wins easily over a shore line.

The solar charge controllers are very easy to set , and reset , so sitting charge voltage or underway style charging is a rotary flick away.

Most folks will not live a Spartan enough life for solar to do much except help out a bit.

BUT that "bit" can mean the difference between batt replacement after 2 years or 6 years.

Sadly its not a perfect world , so after 120 years were still waiting for the batt set decimal place to be moved one place over.