Electric Motor and a Honda 2000 Generator?

[misfits]

Originally Posted by wildernessdave

We are looking at electric power for a 27 foot sailboat and my reason for asking about powering it with a generator is wondering if it would be possible to transit the Erie Canal slowly by powering the boat with a small generator, not motor around the world. .

There are many folks that are happy with their electric conversions. Then there are some that are not. It all boils down to how you plan to use your boat " long term". Transiting the Erie Canal or the AICW, if you went electric there's nothing stopping you from using from using a generator to make a trip like this. If all else fails you can always toss a 6 or 9 HP motor on the transom. In the long run it will not be cheaper than doing a diesel repower but you won't have the hassles associated with having an inboard ICE.
I am going down the EP road & have decided this is the route I'm going if EP doesn't meet all my needs cause I want to do the canal/ loop in a couple of years.
Flak jacket is on....

[tkeithlu]

1 Kw = 1.3 HP, at 100% efficiency. Think how many horsepower a gasoline outboard would have to be to move your boat. Add at least 25%, 50% would be better, given energy loss and not wanting to burn up your genset by running it at its rated capacity. Now you know what size genset you need. Running on batteries? Read just a little bit about U-boats running on batteries under water. Huge charging diesels, huge battery banks, and 3 knots for four hours or something similar. Don't even think about it.

Basically, you're trying to replicate diesel electric drive using a genset. Diesel electric boats (minesweepers are a good example) need diesels larger than they would need for straight diesel drive. You're going to need a genset with an engine larger than the engine that would do the same job hooked up to a shaft.

Aside: minesweepers use diesel electric so you can reverse the field, and apply huge reversing torque, by flipping a very large switch. They can stop from flank speed in 1 1/2 lengths, which is useful when you are about to hit a floating mine. Friend of mine did it once. It worked, but put the fantail under water.......

[GrowleyMonster]

I replaced my Atomic with a 5kw Brush less DC motor a while back. Total cost after selling the old infernal combustion clankersmoker and including a 220ah 48v bank was under $2500. I no longer have a mast. Took it down so it won't shade my solar panels which actually are not up yet. I will eventually have 2kw of solar and probably a portable generator as well.

For high power demand situations the typical electric drive setup will not do the job. For just docking and stuff, it is absolutely mahvelous. For slow motoring o n calm waters it is very nice. I can toodle around all day on lake Pontchartrain after an overnight charge from shore power which cost about 1/3 I guess what gas or diesel costs. A portable generator is an inefficient way to charge the bank and is mostly valuable as a backup. Solar in any large amount can be difficult to arrange with all the shading of mast and sails.

The big bank comes in handy sometimes, for other stuff.

Best bang for the buck in spite of their drawbacks vs lithium is the 6v GC2 Energizer golf cart battery sold by Sam's club. They are about 80lbs ea so that is 640lb of batteries. I will be adding a second bank probably this winter. They were $85/ea when I bought them three years ago.

My motor is a Motenergy ME0201014201 and reduction gear is an enclosed Baldor cast iron gearbox. Controller is from Kelly. I have spare motor cause I bought two, since they were cheap. Spare controller is a long story. Also have a ME0913 12kw motor that will work with the same controller. Motor mount is just home fabricated steel. Prop is 14x10 3 blade. Range varies WILDLY depending on power level. You might think 220ah means I can get 100a for 1.1 hours and still have a 50% charge but it doesn't work that way. I would actually get about half that. OTOH if I ghost along at 2a I get about 70 hours runtime at a bit over a knot before the batts are down to 50%. This without any recharging enroute. The batteries are everything. Lithium can discharge deeper and are lighter. And they cost about one diesel engine worth of cash. Bigger bank needs bigger charger. FLA batts need equalizing periodically for long life. A big bank takes up space on a small boat. They must be covered so you don't drop metal objects on them and weld/ melt stuff, start fires, shock the daylights out of you, or ruin the batts.

Keep in mind that most motors do not have a thrust bearing, and are not rated for any axial load at all. With direct coupling to the prop shaft you would probably destroy the motor in minutes. So you need a thrust bearing or a transmission of some sort that serves the purpose. Most small boats use a belt and pulley system and you can get one prefab or diy it yourself. You will need to intelligently match motor, voltage, reduction ratio, hull, prop, and power requirements and you will still do a good bit of fine tuning when it is all said and done.

If you have an old long shaft outboard laying around that doesn't run, you might replace the infernal combustion part with a 12kw or 10kw motor and simplify things a little. You will still need that big bank though.

[StuM]

Originally Posted by GrowleyMonster

I no longer have a mast.
...
GrowleyMonster
1976 Cal 2-27 sloop, MR WIGGLES

You no longer have a sloop either

Good description of an appropriate use case for EP.

[ErikFinn]

30 years ago we had a 24 foot grp boat with a 6hp diesel. For normal day sailing nice conditions it was good but I remember on one occasion we went out after a storm and the waves were about 2 meters with short intervals but wind not much, less than 10 knots, and we were unable to motor against the waves, just stayed stationary even with full power. After about 10 minutes and a lifeboat having checked us about we gave up and turned back.

While I realise this thread was started what 6 years ago but I wanted to comment anyways. There are many daysailer sail boat without any engine at all and they do just fine considering the limitations. Add an outboard and you get more flexibility. Change to el motor and hmm maybe it will work for you if you keep in mind the limitations. Just don't go crossing oceans and expect no issues. On the other the Atlantic has been crossed in a rowing boat..

[valhalla360]

For the eire on a 27' boat, you could probably do it. It would be slow and there would be times, it annoys you fellow boaters as you would likely be limited to 2-3mph and in narrow spots they would have to wait to get around you.

But a whole lot simple and cheaper to just get a 5hp outboard and strap it on the back.

If you are playing the eco game, the generator idea is worse than just using an outboard.

[GrowleyMonster]

Originally Posted by valhalla360

For the eire on a 27' boat, you could probably do it. It would be slow and there would be times, it annoys you fellow boaters as you would likely be limited to 2-3mph and in narrow spots they would have to wait to get around you.

But a whole lot simple and cheaper to just get a 5hp outboard and strap it on the back.

If you are playing the eco game, the generator idea is worse than just using an outboard.

Actually I have plenty of power with my 5kw setup. Just not for very long. I can do just under hull speed for 0.83 hours according to my peukert spreadsheet and still have 50% SOC and I have not done an actual endurance test at that power level but I did run it wide open (about 140 amps) for 20 minutes once. This without any onboard charging. Bank was still way over the halfway mark.

Don't forget about shore power charging. So cheap it is almost free. Helps to balance out occasional use of the inefficient generator. Getting at least 400 watts or so of solar panels up would help extend the zero emissions range considerably.

But yeah, with electric, it is good to rethink the need for speed, because at half of hull speed it is a lot easier and practical. What's the hurry, anyway? I have sailed all day and never got over 2kts many many times.

If you really must go fast, get a diesel. Or yeah, a gas outboard. If you might ever be stemming a 3kt current and heavy wind and seas, get a nice big diesel and the biggest prop you can swing. For many folks who don't foresee ever encountering such conditions, the advantages of electric are very attractive.

[GrowleyMonster]

Originally Posted by StuM

You no longer have a sloop either

Good description of an appropriate use case for EP.

Touche. Changed my Sig.

[valhalla360]

Originally Posted by GrowleyMonster

Actually I have plenty of power with my 5kw setup. Just not for very long. I can do just under hull speed for 0.83 hours according to my peukert spreadsheet and still have 50% SOC and I have not done an actual endurance test at that power level but I did run it wide open (about 140 amps) for 20 minutes once. This without any onboard charging. Bank was still way over the halfway mark.

Don't forget about shore power charging. So cheap it is almost free. Helps to balance out occasional use of the inefficient generator. Getting at least 400 watts or so of solar panels up would help extend the zero emissions range considerably.

But yeah, with electric, it is good to rethink the need for speed, because at half of hull speed it is a lot easier and practical. What's the hurry, anyway? I have sailed all day and never got over 2kts many many times.

If you really must go fast, get a diesel. Or yeah, a gas outboard. If you might ever be stemming a 3kt current and heavy wind and seas, get a nice big diesel and the biggest prop you can swing. For many folks who don't foresee ever encountering such conditions, the advantages of electric are very attractive.

Assuming the guy wants to run the Erie canal (no sailing possible) and assuming he wants to cover 20-30miles in a day, .83hrs at say 5kts isn't going to cut it and 2kw generator which really only puts out 1.6kw continuous (assuming the battery charger can actually absorb the full 1.6kw), isn't going to feed a 5kw motor. The generator might give you an extra 20minutes before running the batteries down.

I appreciate that you admit the only way to make electric viable is to substantially reduce you assumptions regarding capability. I suspect the vast majority of cruisers already feel 5-7kts is slowing down and taking it easy. We sure do, joking about having circled the east half of the USA at a brisk walking pace. To cut that in half or more again for negligible cost savings (or likely an overall cost increase), just doesn't make sense and limits it to enthusiasts.

Paired with a 5kw generator and appropriately sized charging system on a 27' monohull and now it's getting viable for most calm conditions. Still an issue if you need to fight a heavy headwind or current but much more viable...but a 5kw portable genset is hard to find space for on a 27' boat and really isn't particularly efficient.

[rwidman]

Originally Posted by wildernessdave

We are looking at electric power for a 27 foot sailboat and my reason for asking about powering it with a generator is wondering if it would be possible to transit the Erie Canal slowly by powering the boat with a small generator, not motor around the world. I understand the limitation of electric motors, but I also understand that there are people who are very happy with their electric motors.

Rising Star seemed to have liked his electric motor set up from what I can tell from what I can tell. My wife and I are just trying to gather information to see if an electric motor would be a good solution for us. I understand it is not the right solution for many people.

In case I wasn't clear in my previous post, burning gasoline to produce electricity to run an electric motor is not as efficient as burning gasoline to drive the boat directly.

It doesn't matter where you are doing it.

[GrowleyMonster]

Originally Posted by valhalla360

Assuming the guy wants to run the Erie canal (no sailing possible) and assuming he wants to cover 20-30miles in a day, .83hrs at say 5kts isn't going to cut it and 2kw generator which really only puts out 1.6kw continuous (assuming the battery charger can actually absorb the full 1.6kw), isn't going to feed a 5kw motor. The generator might give you an extra 20minutes before running the batteries down.

I appreciate that you admit the only way to make electric viable is to substantially reduce you assumptions regarding capability. I suspect the vast majority of cruisers already feel 5-7kts is slowing down and taking it easy. We sure do, joking about having circled the east half of the USA at a brisk walking pace. To cut that in half or more again for negligible cost savings (or likely an overall cost increase), just doesn't make sense and limits it to enthusiasts.

Paired with a 5kw generator and appropriately sized charging system on a 27' monohull and now it's getting viable for most calm conditions. Still an issue if you need to fight a heavy headwind or current but much more viable...but a 5kw portable genset is hard to find space for on a 27' boat and really isn't particularly efficient.

Actually yes it will feed a 5kw motor. It just won't feed it 5kw. Keep in mind that the hypothetical 1.6kw at 48v is about 33a. At that power level my own 27' boat is doing in excess of 3kts. That would be without taking anything out of the batteries. Take out 10a for 10 hours and the total 43a should be good for 4kts or a bit more. Say you get an average 200w from solar... that's another 5a and now the boat is a fair amount over 4kts. I admit that the whole experimental aspect of such a trip is the biggest reason to do it but it is real world feasible even if a bit inelegant and fiddly.

So for a once off canal trip it would be doable, if just barely. Remember, shore power charging when stopped for the night will help a lot. For long canal transits on a regular basis, I would actually recommend a Beta 10 diesel for a boat that size, with maybe an electric motor piggybacked to the shaft for a hybrid arrangement. That would actually be quite efficient. The Beta is inexpensive and comes with nearly everything you need except the hull, shaft, and prop. The piggybacked motor could charge the batteries at a user variable rate via the controller, or freewheel at no load, or be uncoupled completely via a clutch. Or turn the shaft with the engine trans in neutral and engine stopped. Remember, the boat can start the day with a fresh top off of shore power in the batts. Any small amount of solar would help as well. It's like free diesel. Still have the foul diesel stench but you would only suffer the infernal racket of clattering valves and pistons for probably half the day or a bit more. I considered that setup for Mr Wiggles but I didn't have the funds for the engine. Plus, well, I like not having fuel onboard.

[Capt.Fred]

Cruisers and Sailing forums,
I have a few minutes now waiting for daylight, to go outside and work. My electric motor was a success, but sadly not really practical for all conditions. e.g. I could motor sail across the Gulf of Mexico, using the Honda 2000 without using the batteries. At low rpms and under full sail I would cruise along silently close to hull speed in relatively light winds. Now for the however. However, when things get rough against current a/o wind, the generator a/o batteries can not hack it. The electrical system has not the endurance required for any thing but a rough short haul. The good ole stinking, noisy, reliable diesel will carry you through for hours on end.
Happy Days,
Capt. Fred

[StuM]

Capt.Fred, thanks for posting that follow up. Too few EP proponents ever post their "howevers".

[ErikFinn]

Lovely!

[smac999]

Originally Posted by SURV69

I've never been on a sailboat that had it's motor going full-bore.
.

I guess you haven't been in current. I've done 7kts cruising down a channel and 1 knt full bore coming back. I have seen tug boats losing ground at full bore up a channel. when they miss timed the tides