solar power

All that to get a boat out to open water?
While I don't question the advice as for living on land I question the need to do it for a mere 8mi. round trip.
Read carefully all the adjectives used in that post. Caching, cachibg $$$$. Sounds like you WANT a project and not a practicle solution.
Thats cool, I have more money in a houseboat project than it will EVER be worth. Good luck.

 

I second Jonathan's point about the voltage... forgot to mention this earlier, but a 10 hp motor on 12 volts, will draw over 600 amps. Look at the main bus on a solar car for inspiration. Here, a motor rated at perhaps 5 kW peak, will typically draw from a 110-120 V battery bank, thus drawing a bit over 40 A at full throttle. These cars can generate 2 hp indefinitely from a solar array of 8-9 square metres (1500 W or so), and can generate that same 2 hp for over three hours with the array unplugged, running on their 4.5-5 kWh battery.
In your case, producing 10 hp for one hour would require at minimum an 8 kWh battery. You'd have much lower losses storing that energy as eight 1 kWh batteries in series (96 V), than one big battery at 12 volts. I'd be tempted to go a bit higher than you need on the battery capacity; this will make each charge-discharge cycle shallower and thus make the cells last a lot longer.

 

I think ir's more trouble than it,s worth. BUT...... take a look at this.
http://www.glen-l.com/designs/special/electricdrive.html#avail

 

Steam. Fer GODS SAKE!!! You boys down in Gator country outa understand good ole steam! The Robert E. Lee wasn't powered by SOLAR PANELS. . .

When the poles melt (hah!) and the oil runs dry look for articles on the power plant that fueled the Stanley steamer. Something like 62 moving parts and unlimited hp. They never blew a boiler and were still winning time trials in the 1950's. With original tech its definately a cumbersome engine, but today we have the materials to build much lighter, cleaner and more efficient steam power sytstem. You can power a prop as easily as a side wheel. Good way to recycle biomass as well.

Sorry Longliner I couldn't resist.

 

4 miles in 20 minutes in a 32 foot displacement boat with 10 Hp...does not compute...does not compute....

Also, an 8D battery at 250 A-H and 12VDC is about 3000 W-H, of which about half might be available, or 1500 W-H. And 10 Hp = 7450 W, so even if everything was brand new and set up with an impossible 100% efficiency and you could draw it down as fast as you wanted, you'd need at least five 8D's to run 10 Hp for an hour.

And another 5 to get back upriver....

You probably don't need all 10 Hp to get this boat to 4 knots, but still, one battery ain't gonna begin to cut it.

 

Solution to too many heavy lead batteries: Saehan's lithium-ion-polymer cells with power densities over 120 W*h per kilogram, as seen in MP3 players, portable computers, and top competition solar cars. Look for them on http://www.saehan-enertech.com/ , you could probably build a pack for your boat with a $$ tag in the low five figures
Needless to say, the cost of efficient electric storage technologies is still kind of prohibitive for a lot of applications.

 

Spend a pound to save a penny.....I'm with Ted etc. A little 4-stroke outboard will be cheaper, infinitely less complicated, more reliable, lighter, take up less space, faster, less hassle, ..... need I go on?
Solar may well have its place, but this aint it

 

http://www.vonwentzel.net/Battery/ . Battery info.
Why not nuclear power? Sorry, just being silly.

 

Newb question here. Just curious. What happens if the batteries get submerged? Electroshock? What kind of precautions are typically installed to prevent this?

 

If it was a gel or glass mat impregnated it would just drain off to full discharge, as they are both sealed type batteries.. The devil to pay if it's a lead acid type.
BUT... I get your point. Do you abandon ship & save yourself OR drown trying to dismantle & salvage your $30,000 aux motor system?

 

I was just laying up a car part and my thoughts drifted to this thread. I did a few searches and found some relevent info. Since this is a nautical board, please don't think of this as a thread hijack. Think of it, instead, as thread piracy. Arrrrr!!!!!! So now...

What about Propane propulsion?

Now, I know that it doesn't have the energy density of gasoline. And I know it makes little sense for a large boat. And I know that there's conversion costs. HOWEVER....

For a small sailboat that only needs a small outboard for getting in and out of a marina (a few miles or less), and if you already have an LP stove on board, why not save the space and weight? Why add gasoline when you already have storage for LP? Why not take advantage of existing systems, rather than adding additional ones? For the environmentally conscious, I might point out that it burns cleaner too...

I guess I'm thinking in terms of something substantially smaller than the original poster's 32 footer. But it seems that the principle would still be valid...

 

Burns cleaner, and you don't pay road taxes on it.
You'd want more tankage though, for propane propulsion, than most boats carry for their stove. Remember a "100lb" propane tank actually takes up about 16"x16"x5', and weighs over 175 pounds. Along with proper ventilation and fuelling systems, since you don't want to (a) blow up the marina, or (b) carry 175 lb tanks in and out of the bilge. A stove or BBQ uses very little propane compared to an engine. But it does burn nice and clean, and would be a good option for an auxiliary if it were more readily available waterside.

 

OK what do you think about this? in todays world I can purchase a 20 hp mercury 4 sroke outboard,new for about 2300 us dollars , on my boat ,at the overhang,I can put in a well,per print on the 1967 spencer Im building,but what about electronics? radio-2of them ,loran or gps -2 of them, and a bottom machine or chromiscope for fishing ,,running lights exc,,, would a bigger battery and solor panal be efficiant?Ive talked to people here at lake erie that only fill thier tanks once a year ,the upside would be if catasrophic engine failier ,,,,you undo 2 clamps and replace,dont want to put the outboard on the stearn,ugly I think ,,,,,,,all critisism is welcome ,longliner

 

Go for solar power.

My gf bought stock in a solar power investment company so it would benefit us

The company I curently work for have made some solar powered river boats.
I can go and check what I can find out about them.

 

The newest trolling motors can put out about 80lb of thrust .

This is equivelant to what you would get ftom a 4 hp outboard.

Borrow one , and see if it meets youre speed requirements'

8D is a size , like "36D cup" and does nor specify the batterys construction or use profile.
For an electric trolling motor ONLY a deep cycle , not a starting or RV "marine" , should be selected.

FAST FRED