Regeneration

For a sailing boat you can freewheel the propeller when under canvas. It is then possible to recuperate energy from the propeller with careful control in the hybrid. Most propellers are not designed to optimise regeneration and are not particularity efficient here. However a useful amount of energy can be generated from a standard prop.

The chart left shows typical power that can be regenerated under sail. As you can see although the power levels are low on an extended passage useful amounts of energy can be obtained and stored in the battery for future use on board.

Extra drag is incurred (you don't something for nothing) but if passage making in the trades you will be up at hull speed and will notice little difference. If minimising drag is essential then regeneration can be disabled.

The Video below shows regeneration in action.