Don't fight the Power

Sep 22, 2018
1,869
Hunter 216 Kingston
Doubtful....While it would be nice to keep the weight low in the boat, Murphy's law states that heavy batteries that replace keels will regularly fail and require replacement on an all too often schedule..
I never liked that Murphy guy! ;)

I was/am joking about keel replacing but if there was a cavity inside the keel that had a battery housing that could be raised for battery maintenance it might work. The more storage the greater the range.
 
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TomY

Alden Forum Moderator
Jun 22, 2004
2,758
Alden 38' Challenger yawl Rockport Harbor
I never liked that Murphy guy! ;)

I was/am joking about keel replacing but if there was a cavity inside the keel that had a battery housing that could be raised for battery maintenance it might work. The more storage the greater the range.
You're right about low. My old boat has 80 gallons of fuel tankage below the cabin sole. The tanks are integral to the glass hull but above the lead keel which is bolted on to the hull. These tanks were designed for the prominent gasoline engines of the day (50-60's) that required big fuel tanks.

Integral fiberglass pipes at the bottom lead any bilge water from forward to beneath the tanks and into the deep sump so these spaces would stay dry. You could place batteries here that would be below the sole yet easy enough to maintain beneath the lifting cabin sole.

The trick would be what batteries would fit the space?

I'll mention this to the next owner. :)
Tank tops.jpg
 
Sep 22, 2018
1,869
Hunter 216 Kingston
The trick would be what batteries would fit the space?
There have been some pretty amazing advances in 3D printing and solid state battery tech. Who knows maybe print your own custom shape??? ;)

A more realistic idea would be something like what Tesla has done with their auto battery design. Lots of small cells linked together to form the “battery”.
 
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Oct 19, 2017
7,732
O'Day 19 Littleton, NH
I am really liking the look of All U Get's
Magnetohydrodynamic drive.

-Will (Dragonfly)
 

capta

.
Jun 4, 2009
4,766
Pearson 530 Admiralty Bay, Bequia SVG
If I needed to repower, there's no question that I would choose a Gardner diesel engine. The last one I had on a boat, a one hundred and twenty five ton steel motorsailor, pushed the boat at ten knots under most conditions (like ST.T dead into the wind to St. M. in Christmas winds) sipping a miserly five gallons of diesel an hour. I(n milder conditions, as the eight cylinder engine was actually eight individual one cylinder engines each with it's own cooling and lubricating systems, I could shut (open the compression release) down every other cylinder and get the fuel consumption down to around three gallons per hour, still maintaining ten knots.
Since cruising RPMs were 375, it was only necessary to change the oil about a quarter as often as a 2k RPM engine. And just for giggles, once at cruising RPMs, I could go down to the engine room and crank a prop shaft drive belt tight, powering a 380vac, 50kw generator and shut down the Onan(s) cutting fuel consumption even more.
Gardeners are no longer manufactured, but there are several companies (I know of one in Scotland and another in NZ) that stock parts and sell reconditioned engines. Obviously the model described above would be too large for most of our vessels, but there are plenty of smaller Gardener engines that would give us reliable, trouble free service. If I had a Gardener I wouldn't even be slightly tempted to go electric, as I'm sure the Gardener would be more reliable, economical and environmentally friendly.
 
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capta

.
Jun 4, 2009
4,766
Pearson 530 Admiralty Bay, Bequia SVG
If I were King..... It would be gen-set low in the boat. Say in a bilge type area. It would power all the electrics including electric drive.. Oh and diesel gen-set for sure.
I've seen plenty of under the floor gensets, mainly on Hunters, and I can't imagine the headache that maintenance is. I intentionally bought a boat with an honest walk in engine room with 360 degree access to both the main engine and the gen set, never mind the A/C units, refrigeration, watermaker, etc., because I knew that if maintenance on my mechanical systems was a pain, it wouldn't get done as frequently as it should. Tearing apart the boat or reaching down into the bilge with one's fingertips to change the oil and filters is not conducive to regular maintenance.
If you are operating in salt water, anything in the bilge has a very limited life span, including a 10k+ genset. Should you ever have a serious amount of water in the bilge, say from a broken hose, you can kiss that genset goodbye. I hope you plan on carrying very good insurance.
 
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Oct 19, 2017
7,732
O'Day 19 Littleton, NH
I intentionally bought a boat with an honest walk in engine room with 360 degree access to both the main engine and the gen set
That is the thinking I was raised with. Our live-aboard was designed with just such an engine room, not a compartment. That's the working commercial mariner, mind set.

Ideally, my dream sailboat has an engine room that is also a watertight compartment in the middle of the hull. Full bulkheads, bilge to deck, and a lock down door, passageways on either side from aft cabin to main salon. Twin electric screws and battery bank running right down the center. Large deck hatch can be opened overhead.

-Will (Dragonfly)
 
Oct 6, 2007
1,023
Hunter H30 1982 Chicago IL
I’ll stick with my dependable little 38 year old Yanmar.

If I suddenly needed to replace it for some reason, I would probably look at three options: electric and either a new or rebuilt Yanmar. I guess a fourth option might be the Beta diesel just because basic maintenance looks a little more convenient, but I’ld likely default back to Yanmar based on reputation and my good experience with it.
 
Apr 5, 2009
2,774
Catalina '88 C30 tr/bs Oak Harbor, WA
You're right about low. My old boat has 80 gallons of fuel tankage below the cabin sole. The tanks are integral to the glass hull but above the lead keel which is bolted on to the hull. These tanks were designed for the prominent gasoline engines of the day (50-60's) that required big fuel tanks.

Integral fiberglass pipes at the bottom lead any bilge water from forward to beneath the tanks and into the deep sump so these spaces would stay dry. You could place batteries here that would be below the sole yet easy enough to maintain beneath the lifting cabin sole.

The trick would be what batteries would fit the space?

I'll mention this to the next owner. :)
You could build a LiFePo4 bank in there with prisimatic cells.
 
Sep 22, 2018
1,869
Hunter 216 Kingston
You could build a LiFePo4 bank in there with prisimatic cells.
I wasn’t sure if I knew what prismatic cells were so started down the interweb rabbit hole, turns out I did know but I came across this reference.


I also came across this which seems to indicate that Tesla has chosen to include this in some of its battery’s

 
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Apr 5, 2009
2,774
Catalina '88 C30 tr/bs Oak Harbor, WA
I wasn’t sure if I knew what prismatic cells were so started down the interweb rabbit hole, turns out I did know but I came across this reference.
I have been doing research on the DIY LiFePo4 batteries with prizimatic cells. In the next year or two, I will need to replace my (6) 6-volt pack for my motorhome and the 4D lifeline for my C30. I can build a 390AH pack with aluminum cased cells that will fit in the same area as the 4D. With all of the parts, i will not cost much more than the (6) 6-volt lead acid+ the 4D Lifeline. I could then use the same pack in both. boat in summer and motorhome in winter and just keep a single Group 27 in place in the off season.
 
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Sep 22, 2018
1,869
Hunter 216 Kingston
Interesting strategy moving the pack between “devices” ;)

I’ve been reading about supercapacitors and came across this. The speed of evolution of all this tech is pretty amazing!

 
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Oct 22, 2014
20,993
CAL 35 Cruiser #21 moored EVERETT WA
The Philadelphia experiment.
No I think the idea was in the book "Hunt for Red October". The "Caterpillar Drive" used on the silent Soviet sub skippered by Sean Connery.

 
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Oct 19, 2017
7,732
O'Day 19 Littleton, NH
The Philadelphia Experiment was a project overseen by Nikola Tesla and shrouded in intense secrecy. I've heard lots of explanations as to what it was all about, from invisibility to time travel and even teleportation. However, the description of the coils of wire laid all along the interior of the USS Eldrich's hull, coupled with Tesla's earlier assertions that a ship on the ocean would be an ideal project for electrico-motive force leads me to believe that the Philadelphia experiment was intended to find a silent alternative drive for naval ships. The accidental electrocution of the crew ended the experiment. What I want to know is, where are the successful test models? One doesn't expend those kind of resources and time in an experiment of that scale without successful small scale modeling, no matter what the nature of the project.

-Will (Dragonfly)