Conversion to Electric Motor

[CharlieJ]

SkiprJohn #42

I could be wrong here but I just returned from a trip where motoring was more than sailing because of contrary or non-existent winds. The sun was strong but electric would not have done up to 3 day periods of constant motoring. Maybe a hybrid would do it but then I would have had to have two power plants and it seems cost prohibitive.

From my #35

...boats that remove their auxiliary ICE, and use the diesel genset to power both the electric propulsion plant and the house loads.

The points that I am trying to make are that their are several voyaging profiles, from an afternoon on the water to circumnavigation. A hybrid solution with a single diesel on board running an adequately sized genset is the more "correct" solution for a blue water vessel.

As another example; one of our Owners removed his aging Perkins 4-108 from his Hylas 44 and replaced it with one of our a 12kW electric propulsion systems, left his 5.5kW genset (undersized but in good shape for now) in place and cruised from Annapolis to Florida down the ICW, went to the Bahamas, returned to Florida and then to Texas. He is very satisfied with his installation.

[Hyprdrv]

Wow I just love this topic and how things get twisted when it comes to electric Drives.
First Electric Lagoon Crosses Atlantic to Annapolis...Then Heads to Tortola

This was the first of 3 Lagoon 410's, I own the 3rd and last one built.
Built in 2004 and still running strong, here's a 41 foot Cat that has traveled far. I'm still learning to sail so have spent the last 4 years in the Chesapeake Bay. Over that period of time I've "used" 30 gal. of diesel. I've burned 80 gal. because I was afraid the fuel was going to go bad. My cat "Electra Glide" was brought over on it's bottom and sailed the Islands for a few years then brought up to the Bay. I'm running a 6 year old bank of AGM's and plan on going Lithium when these are gone. I'll get twice the energy out of the LiFePo4's at half the weight and 1/2 the size, yes at twice the cost but the life expectancy will probably be over 15 years. The motors are rated at 200,000 hours.
Here's what "Tony" the delivery captain had to say. He brought "EG" (Magic then) up to the Bay. I ran across another post of his and contacted him to ask a few questions. Here is what he said.

I "drove" Waypoint (electric L410) in her early days in Tortola and then delivered Magic ("2nd generation" electric L410) up to the Chesapeake from BVI. The difference between the 2 was quite significant and it was good to see improvements had been made.

"However - Dr West's electric Leopard - You don't mention re-generation? I thought that was the whole point of the system and indeed, I got Magic up to the East Coast on a thimbleful of fuel and had all the electricity I could handle. One thing I thought annoying was that with regeneration, you could cook the batteries if you weren't careful so you had to run something to burn off excess power. Surely a shunt regulator could have been put into the system - even simple wind generators have them. But, having said that, I found that bleeding off excess power by using the main motors made for some extremely good daily mileages: hardly purist sailing but pretty efficient in getting from A to B.

From that: I see that as a passage-maker, the electric concept is brilliant with regeneration and uses very little fuel. I don't see it quite as happy as a BVI charter boat however: there's very little sailing to re-generate with and so the generator is going to be running for quite some time to top off the batteries (I understand that they click in automatically now on low voltage which seems sensible). Further to that - diesel generators, being smaller engines, probably have a shorter life-span than, say, a 4 cylinder Yanmar (Lovely engines and they seem to thrive on "benign neglect"!). Also, although on long passages on a cat one only needs to use one engine at a time, it is nice (and, arguably safer) to have two main engines rather than just one small generator?

From a personal point of view, although I've always liked the Lagoons, I found that the electric ones made you feel as if you lived in, or near to, a Power Station, with a continuous electrical hum: probably bad sound proofing but it did make me wonder if there were any stray radiations around which might insidiously be trying to fry my brains (or other parts of me)!! Tony "
So a few facts
I have 2-9kw motors
I regenerate under sail.
I have a 16KW genset that provides more than enough power to run the motors 40 hours on the fuel I carry in the tanks.
With a 144V system I use around 50A (total) to run at 6 knots. I've done 8 knots without pushing it hard.
To those who don't have Electric Propulsion but know how to twist "math". Keep on doing what you feel best. I've been watching the posts for a long time on Esystems here and else where. I've seen the total negative go to a somewhat questioning. There are those who do and there are those who don't. Those in between must decide who to believe. Personally I don't care. I saw all those who sat at the dock because fuel was so expensive while I "motored" quietly away.

Steve in Solomons, MD