Low drag !
Reducing drag leads to design more efficient hull shapes with regard to propulsive energy.
This automatically lower the required power, whatever sailing or motoryacht is concerned.
I take great care of that when designing racing yachts but also cruising ones and workboats.
The saving is measurable in speed, fuel consumption, and material thickness.
Here is Bagou, a coastal cruising catamaran powered by electric engines
A cat-boat is more efficient than a sloop due to the reduced drag, the higher aspect ratio and the greater angle of incidence. Proof is not to be made anymore as you watch olympic dinghies.
It is still relevant on bigger boats such as the Ikone range and the 42 footer H2A where simplicity and efficiency combine very well : this just requires to change the way to control the sails !
I also use the cat-boat rig for cat-ketches, on ocean cruising yachts, such as the Medium and Wakame ranges.
Here is the Ikone 7.50, Boat of the year 2016 by the french Voile Magazine.
The wood material used in yachtbuilding is usually light, strong and aesthetically pleasant.
Strong and heavy boats last for a long time mainly because any piece of wood can be repaired or replaced by a new one.
Very light structures may be built when associating wood to light core materials such as foams, balsa or cork. Repair is not that easy in this case.
There is probably a gap where designers and structure engineers could find a quite light wooden material that shipyards could repair or replace for years without exessive use of epoxy resin.
I am looking for this gap.
Here is the Kobe 43' built by Technologie Marine
Flax fibers, flax/balsa or flax/cork sandwich panels with green resins give rise to high specific mechanical properties with a low environmental impact.
I use them as well on cruising baot (Marlin 32') as offshore racing yachts such as the Mini n°791 - in the top 5 prototype ranking 10 years after launching - or Class40' Flax40'.
Here is the internal structure of Mini prototype n°791 (Flax 6.50)