On Thu, 02 Jun 2005 10:13:43 -0400, rhys wrote:

On Thu, 02 Jun 2005 12:43:35 GMT, (Mic) wrote:

Perpetuated Motion
Electric propulsion for boats: A century-old technology may just be
the wave of the future

LINK:

http://www.cruisingworld.com/article...ID=396&catID=0

" Advocates for diesel-electric propulsion list among its virtues that
it's clean, quiet, efficient, and requires very little maintenance.
Another advantage frequently noted in connection with the STI system
is the ability to make electricity--to "regenerate"--when the boat is
under sail."

"While internal-combustion engines are typically described by their
horsepower rating, STI's motors are named for the torque they develop.
An ST 37 puts out 37 foot-pounds of torque or 6 horsepower; Tether
recommends using it on monohulls up to 32 feet and 10 tons or to
replace diesel engines of up to 24 horsepower. An ST 74 puts out 74
foot-pounds of torque or 12 horsepower; Tether recommends using it on
monohulls up to 50 feet and 16 tons or to replace diesel engines of up
to 48 horsepower."

The ST37 is right in the range for my current light cruiser, and the
ganged ST74 is appropriate for my anticipated next boat, which would
be a modified full-keeler.

I'm watching this technology like a hawk. It makes a lot of sense on a
number of levels, but of course, it isn't for everyone.

In the meantime, I'm replacing the exhaust end of my old Atomic 4....

http://www.soundingsonline.com/stories.html?story=2

"Waypoint carries twin 12-hp Solomons Technology ST 74 electric motors
powered by a dozen batteries. The batteries' charge is renewed by
leaving the power plants running when the boat is sailing so the props
turn in the water, transforming the electric motors into an electric
generator. If there's no wind, a 15-kw diesel generator recharges the
batteries, says Mike Stevens, Catamaran Company's Annapolis salesman.
Stevens says Waypoint can run four hours at 8 knots on batteries, or 6
to 10 hours at 5 or 6 knots. He says the electric-powered cat appeals
to the company's most environmentally conscious customers. "They want
to sail with a green wake," he says."

R.