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SVN Solovelanet Global
For "native" installations during construction,
manufacturers generally supply the sail drive with
a fibreglass base to be laminated on the new hull.
For retrofit installations on existing boats, adap-
ter plates are available for Volvo and Yanmar ba-
ses, that make it possible to screw the sail drive
directly, in order to minimize shipyard work. For
other pre-existing engines, appropriate customi-
zations are needed.
Installations with powers up to about 22 kW at the
axis can be made with 48 V nominal propulsion
and current around 500 A. Within these values,
such installations are fairly simple and the risk of
electric shock can be excluded; 48 V is also an in-
dustry standard voltage level for which chargers
and other accessories are available at competiti-
ve costs. Beyond these values, installations must
be carried out with particular care due to the hi-
gher risks caused by the current and voltage va-
lues involved.
Batteries
The most suitable batteries for electric drive are
lithium (Li-Ion) ones, which outperform lead bat-
teries in terms of both duration and amount/qua-
lity of supplied energy.
Above, a 22 kW (about about 30 HP)
Kräutler motor, and below it, a Volvo Penta
D1-30 engine, the thermal equivalent of
the Kräutler motor. The differences in com-
plexity are easy to understand. An electric
motor is made up of very few parts, so
there are few parts that may break and few
parts that need maintenance. A heat engi-
ne, on the other hand, has many elements
that may break and need to be serviced.
In the Mediterranean, during
the summer holidays, a boat sails
between 75% and 85% of the time
under power
