The reason for choosing the Duodrive system is its unique way of delivering faster acceleration, improved top speeds (hello... It's a barge?), better fuel consumption and reduced vibration. Their technology gives a method of creating a duel, counter-rotating output props from a single driven input. The Duodrive system brings significant efficiency improvements and counter-rotating propellers reduce energy waste.

Interjecting the theory for one moment, a Duodrive buyer will have to be a passionate engineer with a wallet sizeable enough to spend monies in re-engineering the under developed product. Be warned!!  Back to the technical benefits...

... The two propellers are positioned immediately ahead of each other on the same shaft line (one shaft counter-rotating inside the other) and therefore rotating in opposite directions.

The negative rotational energy imparted to the water by the forward of the two propellers is cancelled out by the opposite rotation of the larger rearward propeller. The slipstream from counter-rotating propellers is almost smooth and straight, with little twist. It is expected to be 15 to 40% more efficient than a standard single propeller set-up. The benefits are; significantly increased efficiencies through performance gains, reduced operating costs and environmental improvements. The props are smaller in diameter than the standard 28" size for this sized craft, a rather valuable extra for shallow inland waterways. It is a 7-blade solution; The forward 3 blade prop will be a LH propeller, 24" diameter x 19" pitch. The rearward 4 blade prop is a RH propeller, 26" diameter x 20" pitch. The odd number of blades will reduce vibration and loading on the rear cutlass bearing.