Need a Clue: Electric Outboards for the Waorani

TreeHugger

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Hi, I'm an intern at an environmental organization working with the native Waorani people of Ecuador. One of their biggest expenses is the cost of fuel to power the outboard motors on their "war canoes." They are currently using a Yamaha Enduro 40/75 outboard motor on journeys through the Amazon that can last for up to several days at a time between villages.

We are trying to find out if it would be possible to get them some sort of electric motor with a battery pack which could be charged for free from a solar set-up at the village (which *we* would pay for). The only problem is, I can't seem to find an electric motor powerful enough to match the Yamaha. Is such a thing even possible? And if it did exist, what kind of electric motor would it be, and how much power would it need? How much power would it need over time? And is there a way to calculate what such an engine would be like from existing information about their Yamaha? I have a few, more detailed questions, but I think I can save them for a little later.

I am doing what research I can, but as I really know nothing about boating or about motors, I am way over my head on this one, and I'm hoping you guys might be able to help me since the general level of knowledge on this forum seems pretty high.

Thanks a lot.
 

JB

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Re: Need a Clue: Electric Outboards for the Waorani

Howdy, Hugger.

Welcome to iboats. :)

I don't think electric would solve your problem. I know of no electrics powerful enough to replace a 40/75.

My first thought would be to go to 4 stroke EFI outboards, as they would use about half the fuel.

A bit farther out would be Diesel outboards, but I don't know of any larger than about 25HP. They should use a lot less fuel, depending on the availability of suitable fuel.

EvinRude makes multi-fuel etec outboards for the Government that can run on diesel fuel or jet fuel which might offer some advantage.

Sorry I can't be more help than that, but more ideas will be along soon.

Good luck.
 

steelespike

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Re: Need a Clue: Electric Outboards for the Waorani

There is an Electric outboiard but it is only about equal to a 9.9 outboard.
There is a limit to run time. I think range would be the first problem and then charge time.Generally takes at least twice as long to charge ie:
1 hour of use = 2 hours charge and so on.Then there is the cost of batteries
A Trojan lead acid flooded 12 volt 130 amphour deep cycle battery is about $150 here in central NY. there are 6 volt and 8 volt deep cycle batteries at about $60-$80 each.You would need enough batteries to create about 60 to 100 volts.These would need to be replaced in one to three years depending on use and abuse.Then there is the massive solar array big enough to recharge in a reasonable length of time.Not really practical.
If you are serious about saving fuel. If you have the time you can run your boats at displacement speeds if they are long and slender like we see on TV
they are perfect for this.Displacement speed is 6 to 8 mph max.I can't speak for the Diesel outboard But diesel motors will run on almost any oil.
Including reclaimed deep fry oil.And they will push at displacement speeds
and get 20 to 30 mpg.If you can find a supply you can reclaim it your self.
It's a bit of an operation but it can be done.I'm sure if you do a search on the net you will find info.
 

steelespike

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Re: Need a Clue: Electric Outboards for the Waorani

Check the old diesel outboard posting above.Yanmar diesel outboards.
 

TreeHugger

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Re: Need a Clue: Electric Outboards for the Waorani

The boats are about 30 feet long, roughly 4 feet wide, and take about 20 people plus about 3 barrels of gasoline and whatever cargo they need. So I don't know if a little engine could move them at all. I got an extremely rough estimate, from someone who went on the expedition to visit them last year, that the canoes go at roughly 10 mph, but he is really uncertain because it is very hard to tell in that situation.

We've considered teaching them to make their own biodiesel, but I don't know if they would have access to a sufficient source of waste vegetable oil, and buying the oil won't be much better than having to buy the gasoline. I don't think the environment will allow them to grow and produce oil like they would need to be using themselves. They have gardens, but mostly they are hunter-gatherers, so I don't think an agricultural solution will be viable for them. Plus, if we can get an electric solution set up for them, they wouldn't have any costs except for the cost of equipment, which we would take care of for them. If all else fails we will certainly consider just getting them cleaner/more efficient 4 stroke motors, as suggested--but we want to exhaust the other options first.

Recharge time from the solar panels isn't a major problem, I don't think--it might be okay if it took a day or two to charge. They could have one set of batteries charging in the village, and just swap them out for each journey (which, despite the cost of batteries, might still be cheaper than bigger photovoltaics).

I'm not quite sure what displacement speed means, but I can look into it. Part of the problem is that the river is narrow and there are a lot of twists and turns in it, which can slow their speed. Basically, a journey might start at the crack of dawn, going as fast as they can the entire way and slowing down through the bends in the river, speeding up again after the turns and gunning the engine to get over logs. During our expedition last year, the trips were generally 9 hours each day from one place to the next, so they can't really slow down if they want to arrive by sunset.

I get the feeling that we would have to have something custom built, but that might be acceptable. My main concern at this point is that it might involve a dangerous amount of electricity. The calculations I've been trying to do indicated that it would take something like 440 volts to do 45 horsepower for about an hour, and maybe twice that if we use 6 volt batteries instead of 12. So that's twice wall voltage, and probably unsafe to have in a canoe (especially one being used by people with mixed levels of experience with electricity). But this one electrical engineer guy I was talking to on the subway :eek: suggested that there were ways of doing it without having it be dangerous. At any rate, do those calculations sound about right to you guys? I'm uncertain about how long the batteries would last, and I'm not sure I did that part right.
 

steelespike

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Re: Need a Clue: Electric Outboards for the Waorani

If you do a search for electric outboards There are a number of sites.
The most powerful ones come in a conventional outboard design.The other has the motor where the gearcase would be on a conventional outboard.
I don't think that will work for you if your bumping over logs and such.Both motors are rated about 5 hp one said to perform like a regular 9 hp.
The conventional design motor has a max voltage of 60, 10 -6volt batteries.
motor and battery package weighs 750lbs.run time at max power is about 1.8 hours.I just don't think electric is the solution.Even if you could find a motor in the range of 40 hp imagine the battery pack needed and the weight.
Yes all that battery voltage can kill.Then you have the acid problems associated with lead acid batteries.
I think the best bet is to operate the boats and motors as efficiently as possible.Be sure they are propped so they run at their correct rpm.
The boats are definately displacement style hulls.This means they don't plane like typical boats do.If they run at 10 mph at wot(wide open throttle)
they might do 8 or 9 at 3/4 or less. A 45 hp motor uses 4.5 GPH(gallons per hour) at wot. Its possible you could do allmost the same speed and use only
about 3 gph.It takes a lot of horse power to increase the speed of a displacement hull.But when operated close to displacement speeds they can be pretty efficient. High end of displacement speed is 6 to 8 mph.
Instead of spending huge amounts on a system spend money to inhance what you have.You need a tachometer(they can be installed right on the motor, a gph meter and a GPS system to check your speed.Typical outboards need to operate within a certain rpm range at wot.usually about 5,000 to 6,000 rpm.
You can find out the range on your motors.The props If they use props need to be selected so the motors run within their rpm range at wot.
The height of the motors on the transom can be adjusted for the most efficient operation.You want the least anmount of motor in the water
and not ventilate(prop lose grip) and still pump cooling water as well.
Then you can play with the most prudent speed using your gps and gph meter.about 1/3 to 3/4 throttle will usually produce the best speed and still get a reasonable gph.You want the best mpg (miles per gallon)and still travel at reasonable speed.
 
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