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re-e-power

20K views 74 replies 22 participants last post by  sailingdog 
#1 · (Edited)
1
 
#27 ·
Actually I'm open to having just about any publication that wants to go. Not sure they will all be on the same boat at the same time, (we don't want them fighting), but we will be putting out an invitation to most of the more popular and local pubs. Plans so far are for DIY, Good Old Boat, Latts and Atts, Northern Breezes, and a variety of others. Hopefully we can gain some ground in the educational curve.

Thanks
Kevin P
RE-E-POWER.com
 
#28 ·
Genset too?

Kevin, thanks for participating in the forum.

From the numbers given above, that would be a range of 6 to 8 miles with 4 group 31 batteries, or (assuming a linear slope) 16 miles off 8 large batteries. I would want two banks completely isolated with one in reserve.

I use my diesel mostly for getting in and out of dockage, but I also do use it to hold head up into the sea during a storm or when traversing an inlet pass and ICW. The above calculations seem to indicate that the electric system would suffice except for:
- Holding up for an extending period of time in heavy sea.
- Extended "need to get there" type cruising with no wind.
- Long trips on the ICW.

So, I'm now thinking that a diesel genset might be a needed addition, thus going true diesel-electric. The genset could use the old engine intake thru-hole and old exhaust.

Kevin, do you have any customers that use / plan to use the above configuration to extend the running time?
 
#29 ·
Yes, you're on the right track, and yes, there are quite a number of folks planning to run a genset for the reasons you stated.
Ample power on the west coast has a great genset that can handle 100 amps at 48 volts and another one that will put out 200 amps at 48 volts. The other option would be to use an AC generator to power a 48 volt charger. You could for long periods with either of those options very sufficiently under most circumstances.
Using the existing fittings and space for a "gotta have it" power supply, as well as having the gen available to run other house needs such as refrigeration and even an electric stove. Propane can be more of a hazard than diesel fuel.

Kevin P
RE-E-POWER.com
 
#30 ·
Try Again?

Kevin:
As I mentioned earlier in the thread.......it was a Solomon ST-37

First you say you can do 3-4 knots in calm seas & light breezes.......then you say you can punch thru anything a 20-30 hp diesel can do. At what speed are you punching?

Ok, let's say the genset is running, the seas are 5' with 20kt winds on a 40' monohull with 20k displacement ...........what's the expectation?
 
#31 ·
Punching, gensets, expectations...

Anyone planning to enter a "named" race, which at least in the US will probably be requiring ORC equipment conformance, will have to do their installation with these in mind:

ORC 2007 regulations:

3.28.3 A propulsion engine required by Special Regulations shall:-
a) provide a minimum speed in knots of (1.8 x square root of LWL in metres) or (square root of LWL in feet)
b) have a minimum amount of fuel which may be specified in the Notice of Race but if not, shall be sufficient to be able to meet charging requirements for the duration of the race and to motor at the above minimum speed for at least 8 hours

And even not racing, it pays to bear in mind that the ORC regulations are an accepted common standard for offshore safety. Eight hours of motoring trying to hold off a lee shore could be considered way too short.
 
#38 ·
Kevin?

I'm just curious how well they are protected from the salt water surrounding them. On most sailboats, we've got a shaft log that at least drips a little most of the time, and seawater incursion is expected. How do you keep the seawater *out* of your pods, and how well are the internals designed to cope with being flooded?

Could you comment on that side of things?

Is the pod sealed, and expected to stay intact? Or is there a shaft seal, accessible "under" the prop, that needs adjustment from time to time? Or is this a "maintenance free" seal, i.e. that is intended and warranteed for ##### hours of use, to be pulled & returned for overhaul afterwards?

I know units bigger than this certainly can be sealed, IIRC even the QE2 is running on electric "pods" under the ship. I'm just asking how these units address that issue of seals and water incursion. And if water does get past the seal...does the whole pod have to come off the hull, or the boat hauled to repair it? Or can it be repaired and then, purged or something, without the need to haul?
 
#39 ·
By the time I add up the pod, batteries and a genset, I'm approaching over budget. I am told by local marine shop that I can have a Yanmar 2 or 3 cylinder installed for about $8500. Does that sound like a reasonable repower cost?

I want powered cruising to be available for a couple of days, like on the ICW during bad weather.

Those are good questions on how the shaft can turn and not leak back into a fully submerged motor eventually.

PS. I have still not completely ruled out the re-e-power option, but I do know that I will be repowering in Jan. or Feb. at the latest, one way or the other.
 
#41 ·
<First you say you can do 3-4 knots in calm seas & light breezes.......then <you say you can punch thru anything a 20-30 hp diesel can do. At what <speed are you punching?
I think that there is some confusion between two different questions. The motors themselves are full able to "punch" through heavy seas with the performance of a 20-30 hp diesel. The other issue is for how long you can run in those conditions. The motors will do it, but the other side of the equation is how much capacity the batteries have. That is the main variable. The original question involved duration of run at 3-4 knots under easy conditions. Running for 2 hours would be a conservative figure under the light conditions stated.

<Ok, let's say the genset is running, the seas are 5' with 20kt winds on a <40' <monohull with 20k displacement ...........what's the expectation?

This equation is very close to our 43' Columbia. I'll give you the quick answer on how the numbers worked out for us. We have a System 4000 on that size of boat. It has a continuous power equal to a 40-50 hp diesel. The motor is able to draw 160 amps at 48 volts continuously. And 600 amps for short periods of time. 600 amps at 48 volts is like having the temp thrust of a 120 hp ICE. The issue then becomes one of duration. Our Columbia has sixteen 6 volt batteries. Two banks of 8 batteries to make 48 volts each. With this formula we plan to run the boat on batteries from St Joe, MI to Chicago (about 55 miles) in about 10-12 hours (4-5 knots). The hull speed on the boat is 9.1 knots. I hope this helps to clear up some of the confusion.
 
#42 ·
Now as for the issue of water ingress into the motor. I'll re-paste the earlier post and hopefully clear this issue up as well.

<Our system employs (very expensive) stainless steel sealed bearings on the inside of the motor. Beyond that, I will tell you that the man we hired (also very expensive) was a Naval Arch that has been building submarines in the private sector for almost 40 years. Needless to say, he knows what he's doing. The motors are basically designed to be in the water for more than 5 years without any trouble. The prop shaft is made to be just like the shaft that comes out of your boat on a traditional inboard. This is a nice feature if you should ever have a damaged prop and need to put a standard prop on the unit to get by for a time. It is also nice because you can put a standard shaft zinc on it between the motor and the prop. On top of all of that, the 2500 and 3000 come with a tube that goes to the bottom of the motor so that water can be detected and also removed if it is necessary. We have also allowed for an inspection hole (additional option) that we can run a bore scope into to inspect the internal components of the motor. This option also increases the warranty from 2 years to 4 years.

I would also like to add that the motor is designed to be run no less than 5000 hours without leaks. All of this is mute if the motor is damaged. We have a 50% core exchange as well. If, after the warranty is run out, you want or need to replace the motor you will get 50% of the purchase price applied to a factory overhaul. If the factory is gone (heaven forbid). All of the parts will be available and the bearings, seals, and brushes can be replaced from off the shelf parts.
 
#43 ·
The last one,

"By the time I add up the pod, batteries and a genset, I'm approaching over budget. I am told by local marine shop that I can have a Yanmar 2 or 3 cylinder installed for about $8500. Does that sound like a reasonable repower cost?"
If what you need is a system 3000, you'll spend about $5,500.00 on motor, installation and batteries. What you spend beyond that could be anywhere from $2K to $10K depending on how elaborate you want to get. Keep in mind that a generator will also be handy for running power for other house power needs.
-
"I want powered cruising to be available for a couple of days, like on the ICW during bad weather."
The motor draws 3800 watts under full continuous (max cruise) power. Charging the batteries via a genset, or by using an AC generator via a battery charger would enable you to cruise under continuous power. Of course we haven't mentioned the use of solar, Wind gens, or the regenerative use of the motor itself under sail.
-
"Those are good questions on how the shaft can turn and not leak back into a fully submerged motor eventually."
Again, this is an issue that has been thought through completely and explained earlier. I would be happy to answer any questions about this in detail on a one to one basis.

I hope that this helps!

Kevin P
RE-E-POWER.com
 
#44 ·
In summary it looks like an aux genset would be a mandatory requirement for the system to be viable for a cruiser and needing power at any time.

So, considering the percentage of sail time vs. time under power, the question is generator size. Would a small air cooled stand alone genset from Home Depot work (doubt it)?

I want pure electric with pure electric regeneration from sail, ideally. That is not going to happen. OTOH, if I have to have a diesel generator with a water cooling system and exhaust I might as well have a diesel propulsion engine with an alternator and the standard house battery bank.

I guess what I'm looking for is a trade-off list. It's real easy to do a conventional repower, but I really like the possibility of having self regeneration energy and no pollution.
 
#46 ·
Very Good

KP:
Thanks so very much for your responses, They are very realistic & balanced which is so helpful for anyone interested or considering e-power.
Best to You & your firm as you help expand the market & make advances for even better configurations in the future.:cool:
 
#48 ·
Thanks, Kevin. I suppose a submarine designer would be a good man for the job, I guess those little research subs ARE all using this kind of technology, duh!<G>

"Let's just all hope that fuel doesn't go over 5 bucks a gallon "
Much as I will hate seeing that, it may be a very good thing for us all when (not if) that happens. $5 is supposed to be the magic price point where all sorts of alternative fuel synthesis processes become economically feasible, at which point we can have investors funding a domestic synfuel industries and we can tell OPEC "Go pound sand!".I was figuring another 2 years or so, expecting to see $4.25 as the shock point this summer with a "relief" back down to $3.75-ish in the fall. And a similar bump again in 2008.
 
#49 ·
Interesting Forum. I too am looking into this, although I have pretty much decided that I need to go with a Deisel Electric system. The power demands are just too much, particularly if one adds other "neccessary" house goodies such as refrigeration and a blender for the margaritas. I am also thinking two drives - one mounted on each side of the existing rudder. (Hinckley Pilot 35' w/full keel) This should give me some close quarters handling that one just doesn't get with a single prop. I am likley going to hold off for at least one more season. The technology and players seem to be getting sorted out.
 
#51 ·
I would like to take a moment to take off my 'RE-E-POWER" hat and ask a question as a member. Does anyone know about the tax credits that are available to EV purchases? Do they apply to electric boats? Do they apply to conversions? This may be an important finacial aid that is being overlooked, and it would certainly help get the EV industry over the hump.

Thanks!
Kevin P
 
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