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Greetings! I have some questions that I'm hoping
some of you might be able to answer.<br>My intent is
to use one or two submersible electric motors, e.g.,
Minn Kota RT 70, 24V, to propel a smaller boat that
will have ample room for two people and two large
dogs. There are ready-built displacement hull launches
available, but they are "pricey" and the layout is not ideal
for our situation. I'm considering an aluminum
fishing boat with a planing hull (e.g., a Lund) as these
have the entirely open layout that I desire with high
freeboard and lots of room for the sea dogs.<br>I
understand the loss of efficiency compared to a displacement
hull compounded by the fact that electric motors are a
bit under powered. Does this make the idea
unworkable? Does weight play a factor? The aluminum runabout
would not weigh nearly as much as the fiberglass
launch.<br>I need to consider initial cost vs. usability. I
can carry extra batteries for cruises of six to eight
hours if necessary. Another possibility is the
"expedition" type canoe of long ago. The hull would work
better, but I also need stability as there is coastal
cruising (New England, primarily CT and RI)
involved.<br>Speed is not critical -- the boat will obviously not
plane with electric propulsion. Am I loony or this idea
worth looking into? I would appreciate any comments,
from anyone who has done anything even remotely
similar or anyone who has any suggestions.
Thanks!<br><br>Doug<br>taliesin@...

hi doug<br><br>you wrote on sept. 5, and i just
signed on and saw your note today, dec. 28, so it may be
too late. but here goes.<br>first, i wouldn't
consider buying a planing hull like the lund if you aren't
going to go fast. you are right about it not being
especially efficient. i would also worry about an aluminum
hull with electric motors and electric system, since
aluminum is notoriously prone to electrolysis problems,
aggravated by electricity. <br>the two minn kota rt70s
sounds okay though--but i'm vastly prejudiced--i'm using
2 rt70s to power my 22-foot catalina sailboat, so i
think (naturally!)that's a good choice.<br>next, i take
issue with the idea--and i see it everywhere and don't
begin to understand it--that electric motors are
"underpowered." electric motors have what they have. they can't
be underpowered--or overpowered or any other
powered. a 10 horsepower engine/motor is a 10 horsepower
engine/motor, period, whether it's gas, diesel, electric,
nuclear , napththa, or wood-burning steam-driven. a
horsepower is a horsepower, a watt is a watt, and
pounds/thrust is pounds/thrust. <br>electric motors aren't
(can't be) "underpowered"--but there's frequently a lot
of debate over how to rate them alongside combustion
engines using horsepower as their measurement. the rule
of thumb nowadays is that about 60 to 70 lbs. thrust
equals about one horsepower. so your rt70 minnkotas are
about 1 horse each. <br>whatever boat you pick, you'll
have to decide whether it can be powered by a pair of
one horsepower engines, whether they be electric or
gas or whatever. if the answer is yes, then
everything's cool. if the answer is no, then it's not the
"fault" of the electric motors--you couldn't push that
boat with a pair of 1hp outboards, either, then.<br>i
was going to suggest a pontoon-type boat until i saw
that you want to cruise around CT and RI in
naragansett and the sound presumably--areas where you get
some wind, some tide, and some pretty good chop. it
sounds like you need a reasonably good sea boat--which a
pontoon boat isn't, and which a small aluminum planing
hull isn't, either--like a sailboat hull or catboat
like the previous response suggested. having made THAT
decision, THEN you can think about powering her--and if you
are going out into the sound and the n-bay, you do
need a fair amount of reserve power and reserve
battery capacity for days when the wind and tide are
against you. you said you intended "coastal cruising" in
new england, and to me that can only mean a fairly
rugged, fairy seaworthy boat.