03/26/2011
Meet Eleccentricity, Lamoine’s First Electric Lobster Boat
Lamoine, Maine is not exactly the center of the universe for the electric boat movement. I am being optimistic when I announce the existence of my boat. I don’t even know if it will float, and it’s hardly built. But given my usual lack of social awareness (lack of embarrassment), I am pressing on. I guess I reason that if I invest the money in materials and the project is moving along, what the heck!
Regular readers will have noticed that I haven’t been writing as much lately; I’ve been devoting my computer time to finding out more about the weird world of electric boating. What kind of motor, what shaft speed, propeller diameter and pitch, motor controller, batteries, switches, throttles….the list is endless…and expensive. Ultimately electric boating can offer a day’s cruising for about a dollar, but getting there involves a few thousand.
Starting with the design, an electric boat needs a “displacement hull”. This is a hull designed to have a speed no more than that defined by it’s waterline length. If you push a boat with ever increasing power, it will either plane like a speedboat or squat into the water and make a big wave (a displacement hull). A sailboat is a displacement hull and has a maximum speed related to the square of the waterline length. So a 28 foot sailboat will have a maximum speed of 7 knots, no matter how big of an outboard you put on it or how much wind you blow. To push it faster you need a hull which has a flat bottom and a square transom (rear end). Try to push a boat designed for planing with an electric motor and efficiency will suffer. Eleccentricity is a hull design like a sailboat, with an oval waterline. It will have a top speed of 5.4 knots (6 MPH). I am hoping this speed can be achieved at about 2500 watts, allowing me a round trip to Bar Harbor, 8 miles away on a full charge.
The batteries will be housed in a hollow keel. This is a wacky idea, but if it works it will make a great deal of stability for the boat, since most of the weight (402 lbs) will be as low as possible. I will need a robust bilge pump at the lowest spot to prevent the batteries from getting flooded, which would be bad. The Yahoo group “electric boats” is filled with eccentric but helpful electric pioneers who have offered me help. Stay tuned!
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Filed under Acadia, Out on the water by on Mar 26th, 2011. Comment.
Comments on Meet Eleccentricity, Lamoine’s First Electric Lobster Boat »
Gee, what a smart little brother!