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Electric motors are nice, quite, and easy to stow. But...

My friend and I were out on his weekender, the wind shifted direction and was coming from the direction of our landing. We were about five-mile away and it was getting dark. It was not a strong wind so we decided to head in. It was the boats first time out and still did not have its running lights on, but it was a shack down cruse so we didn't really want to stay out to long. The little electric motor slowly moved us in the direction of the landing and the sun started its down word lag. It was the first time for ether one of use to be out on a Weekender. For a small boat the Weekender had handled well though most of the time that we had been out had been under the power of the small electric motor. With three miles left to go and the sky getting darker the wind had died completely. Three miles, no sweat we would be in before it got to dark. It was about then when I asked Pat if he had slowed down the motor. He replied no. But the motor was running slower. We went on, no wind, no lights and getting darker. The motor was really starting to die and the wind was now little puffs of air coming and going. We watched a Sheriffs boat pulling another boat, but he didn't see us. We were now in the dark, no motor, and the wind picking up from the direction we were going in. We had not really sailed the Weekender up to this point but the wind was blowing at about 3 mph so we turned the boat and let it catch the wind. We had movement, positive rudder and were now sailing but this meant tacking to get to the landing. Now I have been sailing for allot of years so this was not a problem, it would just take time. This was a first for my friend and his little boat was doing fine. The problem was that no one could see us out there. So every time we heard a boat we would watch to see that it was well clear of us. We did about 8 long tacks of about 1/2 a mile each time and about 6 short tacks. Each time it seemed that the wind had picked up that much more. The Weekender handled as well as the factory boats that I have sailed but could go much shallower so we tacked close to the buoy on the last tack. The wind running down the channel that we had to go up. With paddles in hand we spent the better part of an hour going against the current and the wind to get the boat back. The Weekender is an impressive boat, we had gone from motoring to sailing to rowing and other then the running lights and dead battery had been allot of fun. Now for the but part.

The battery had died in less then an hour. With the wind building up as high as it did I don't think we could have used it to get us back anyway. Electric motors always seem to be a little under powered in the long haul. The wiring was redone to make sure we where not losing power that way but with one battery we were relying on it to much. We had this problem two more times even with a 2nd battery on board. If you added the weight of the two batteries you have the weight of a good size outboard. My friend Pat borrowed my 3hp dinghy gas motor but said other then the fact that the battery did not run down it still didn't have enough power. I was able to pick him up a 5hp outboard gas motor at a garage sale. What a difference that made. Yes its smells but it has more power then he will ever need. Say what you want, its better to have a little to much then just enough power. If you

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Thanks for the info Frank. I like the idea of fuel-cells, but I have concerns about the hydrogen problems. It seems that we're trading one centralised fuel economy ofr another, which is certainly why it's getting the ok from the-powers-that-aren't.

Hydrogen as an explosive isn't a concern much (it's probably less an issue than gasoline fumes), but the pressure systems and embrittlement of metal parts is a concern. Plus, it's pretty silly to me to be using natural gas to get hydrogen; just use the methane! CNG is a lower pressure system which is already in use (most busses seem to use it now around here.) It's really pretty clean-burning (compared to gas/diesel/propane), it's simpler.

The real holy-grail is the direct-conversion fuel-cell, which runs on any petrochemical or hydrogen and cracks the hydrocarbon onboard. It's still the same CO2 cycle as burning natural gas, but it's quiet!

It's basically an internal-combustion generator like we're used to, but with no noise or spinng parts. That would be the real answer to my mind, and they've worked well in lab tests. Hydrogen fuel-cells are only half an answer to me, and may distract everyone from the real solution (possibly why we're seeing large-scale support for the system.)

In the meantime, quiet generators are still not that quiet. OK for power while underway, as it's not much different than a 4-stroke o/b. I wish someone would make a nice, quiet 4-stroke 2hp or 3hp. The Honda 5hp we had in the Hydroflier was great, but still too heavy for Weekender use (not really, but a little o/b would be better.)

Dave: 3X6 works out to about 200 watts (max, usually figure about 80% of this in normal lighting conditions) if you use good panels. I don't know if you're using a 12v or 24v motor, but the amps would be either roughly 15A for 12v or half that for 24v. Find out how many amps you're drawing at cruise, and the solar would be able to supply whatever percentage it works out to be. Similarly, if you want to charge while motoring, you need to size your charger to either supply more than you draw while cruising (to top off batteries while motoring, and allow some quiet cruising time) or to supply a percentage of your cruising power needs and make the rest up while sailing with panels or at rest either with panels or gen.

It's pretty easy to figure out, but keep in mind that everything needs a "fudge factor" to allow for the resistances of batteries. Add about 20% more amp-hour supply than you draw and you'll probably work out ok. It never hurts to have too much solar and/or generator available!

Mike

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I just followed the Google link at the top of one of these pages to the Briggs & Stratton Electric Outboard page. Very cool that someone's finally done a better e-o/b. The one that was available before was pretty ancient-tech. The B&S E-tek motor is a really good one. It was bought/licensed from a company in England where it's beeen used for inboard boat applications for some time. The B&S motor is rated at 3hp. which is roughly what they call their E-tek motor. I know that it is far mor capable in the right hands, but the B&S e-o/b probably has its top power output limited. Our EV-developer friends got hold of some of the pre-production E-tek motors a few years ago and beat them mercillessly in all sorts of uses. They were getting upwards of 7+ hp., and one guy said "the upper end is when you start melting things." B&S has set the operating voltage at 48v, which is right at the upper limit as per the USCG (50v), and what I'd chose for a boat drive system. As a note, this is the motor my uncle and I were speccing for his 40' monohull.

They're running Kort nozzles, which look like props with a shroud around it, and that is what's going on, but are actually a little more sophisticated. They develop around 20% more efficient thrust than an open prop, but are limited to slow speeds. They're not planing drive systems, but they're very good for displacement boats and produce a lot of thrust. They get used on European tugs and on fireboats and research submersibles, etc.

A pretty attractive unit, and I hope they get a lot of business. The price is not too bad, considering. One still needs four batts. and lots of big wire, but it's a new product and there's always a time before the price drops.

These would answer the power concerns of any Weekender or Vacationer, but the weight would be prodigious. I suppose if you want inboard ballast anyway, you could consider this.

Mike

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The real promising technology is the one that extracts hydrogen from water using a membrane to allow the hydrogen to collect on one side and the oxygen on the other (like reverse osmosis). I think this is the technology that the HaveBlue boat is looking to use, as it's clean and has the potential to be cheap. You do get CO2 out the tailpipe, I guess, but other than that greenhouse gas, its clean.

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