solar power

[longliner45]

Well what do you think? 32ftsailboat ,displacment10500lb sail area 500sq ft10 hp electrice motor forward and reverse, 1 ,,8d battery 2 2by2 solar panals to charge the battery, and one emergancy 5 hp briggs with a 200 amp altanator for back up,I only need to run 4 miles on power to open water,,,,all sugesstions are welcome,,,,,,longliner

[Figgy]

Thats alot of equipment. Can I ask why? It can't be to save money unless you have the stuff already, is it to be eco-friendly? One more question, am I reading this correctly... 1 battery?

[longliner45]

sure its to save money.....fuel at 3 dollars a gallon,,,,sure its eco friendly,,,, yes 1 battery ,,8-d commercial grade,,stores alott of amps,clean quiet,and after initial cost of about 700 dollars ,,,,,,its all free besides , sailboats didnt have motors before , I think this is the way to go , plus the wieght involved is considerabaly less than what the original plans call for ,,atomic 4 and velvet drive transmission,,why didnt I think of this before? ,,longliner

[ted655]

NO. It's not free after the initial purchase. This is what many think (including me ,once).
Actually solar cells have a life span. Worse, they lose capacity as they age. A particular rating as new, a far less rating, say.... 3 years later and so on. Then there is the amount of times a battery will take a full charge, then a partial charge, then a lesser charge, then... and so on. Also, to get the maximum life from the battery, it takes a fairly strict discharge-charge regime. This schedule rarely fits the actuall intended use of the motor or appliance. As a result a battery has a "real" life of useful power that is far less than on paper. A fairly complicated charge/regulatory system whose componets will cycle only a number of times is also needed.
Ahter all your componets and installation you are STILL going to carry an internal combustion engine??? C'mon man, buy the OB motor and enjoy the wind. Our politicians burn more hydrocarbons on one plane trip than you will for the life of the boat. Besides, they (scientists) say WE have already tipped the Poles over the recovery point. It's all gonna melt now no matter what we do.

[Toot]

4 miles to open water. Maybe 4mph with the 10hp? Maybe 2 gph? $3/gallon. So you "save" $12 a trip? I think you're adding a lot of unnecessary complexity for questionable savings.

Solar power cells have been around for well over 30 years. Every kid has experimented with them and most adults have at least given a passing thought to powering something with them. If it were truly economical, you'd see a LOT more of them. It's not like it's some new technology that most people are unaware of. Plenty of people have priced it out, talked to other early-adopters, and decided to take a pass on it.

To be totally honest, if I were deadset again using a fossil-burner, I'd probably create a wind generator. Think about it:

1. You'll be out in the middle of a large expanse of earth with no trees or buildings to block the wind.
2. Whether you want to or not, you are already carrying along the tall structure for mounting it.
3. There are plans available online.
4. They can be fabricated cheaply out of magnets acquired on eBay, some glue, some wire, a few bearings, and a hand-carved propeller.
5. You could link it to your sail so that as you move the sail, you are orienting the generator to the wind simultaneously through a fixed linkage.
6. It'd sure generate a lot of questions!

What's that? You got a propeller engine mounted up there or sumthin?

The simplest, smallest, cheapest homebuilt models generate 60W/hr with a 4' diameter. I'd think that with better magnets and a serious generator rather than a homebuilt one, you ought to be able to double or even triple the output easily.

[marshmat]

Assuming that you're using good power electronics for tying the whole thing together, it should be workable. But 8 square feet of panel will put out 180-200 watts tops, if you use high-quality silicon cells such as the Sunpower A300. I wouldn't count on more than 140 W from that array. So your panels would serve only to charge up the battery, which would then power the motor for your short bursts under power. Your range under power would not be very far.
I'd be tempted, if there's space, to mount a lot more solar array than you describe. Properly encapsulated in something like a Gochermann ($$$$) or SunKat laminate (the old glass-sheet-over-bare-cells isn't that great), the cells will last for many years. With a good charge controller, so will a good battery.

[longliner45]

the battery will power the motor , the panals are to charge the battery ,and a trical charge at the dock,,the 8d will be for storing amps Im really not seeing a problem here ,,,,only need about 20 minutes running time per use,, more concerned about prop size and motor,all help is appriecated ,,,,,,,longliner

[marshmat]

If you only need 20 min under engine, then that sounds a lot more reasonable.... do you have any specs on this "8D" battery, or a link to the manufacturer?
A friend of mine is working on a similar electric setup for a slightly smaller sailboat.... it's definitely workable if you know what you're doing.

[longliner45]

8d is a common comercial grade battery,,,,,used in tractor trailors and fishingboats they are about 20inches by 20inchis and come in various qualitys

[djwkd]

no chance,they may be beyond recovery point but they aint beyond still there point,they aint going to melt anyway,we got tO stop the whole things from melting.i think solar panels are a great idea!

[longliner45]

Its the fuel you got to be concerned with ,I see fuel rationing in the next 5 to10 years ,and guess what ,it wont be for power or sailboats it will be for power companys and military and police and fire crews ,,gotta think ahead

[JonathanCole]

I have been living using solar powered systems for decades. Properly designed, installed, maintained and used they are among the most long-lived and reliable of any type of technology. Panels are typically guaranteed against a loss of greater than 10% of their rated output for 20 to 25 years. Large deepcycle batteries are guaranteed for up to 10 years and properly used can last 15.

Since you are charging at the dock as well, you may get more bang for the buck with a wind generator than solar panels, but they are very sensitive to corrosive environments.

Make sure to use crystalline or poly-crystalline and not thin film solar if you want long life. Also, The voltage rating of the system is important. If your battery is 12 volt you probably won't find a 10 horse motor at that voltage that will weigh less than your boat. However there are DC-DC stepup converters available. At that horsepower you are probably going to be utilizing a motor that runs at 100-144 volts. It will be far smaller and lighter because of the requirement for much smaller internal wires.

I am working on building a fifty foot solar electric live aboard catamaran. I have done a lot of research relating to solar-electric boats. The main thing I think is installing all of the equipment with the proper degree of protection against corrosion. Also your panels won't put out much in the shade of the sails. You have to think out all of these issues before committing to installation, otherwise you'll have one of those well-known bad experiences and you'll be like the guys telling everyone that the technology does not work.

[longliner45]

thanks john Ill be gett up with you ,,,,,,later on as I havent puchased any componants yet ,still shopping thanks ..longliner

[sailsocal]

Originally Posted by JonathanCole

I am working on building a fifty foot solar electric live aboard catamaran. work.

Do you have a web site with more information on this boat?

[ron17571]

if its all free it sounds like its worth a try,otherwise i would recommend a small 4 stroke outboard,all the people who advertize electric power seem to market it to the filthy rich,i kinda like an generater battery electric drive combo.I see a few panels and a small battery ok if the power needs of the boat are small.