Colregs dilemma

Okay, here's a new puzzler for which I cannot imagine there is one
definitive and completely correct answer.

Situation: A sailboat with a DC electric auxiliary motor. What if this
imaginary sailboat is sailing under sail power, but the propeller is
engaged to the motor... but acting to make the motor into a charger to
replenish the batteries. This not only isn't propelling the boat, but
is actually doing just the opposite. So, we have propulsion equipment
being used in it's entirety (not in neutral) even though it's not
propelling the boat. Because the system uses the propeller to turn the
charger, this sailboat will almost always have the whole drive line
engaged regardless of anything else. When it's not being used as a
motor, it will always be "in use". So, under the colregs, would this
be considered a powerboat at all times?

Discuss!