Placing them on sails
is just silly unless you are doing something like a round the world race
is no object. Are you really going to put up your sails
so you can get some solar power? Even just heading to upwind in a channel, you will lose more power from wind
resistance than the solar could possibly produce.
For house loads, an arch with a few hundred watts of panels is typically plenty. No need to mess around with exotic installations.
In reality, we are starting to see solar becoming a serious design consideration. Cats are built with large arches and cockpit
overhangs which provide a place to mount large solar arrays. I suspect, we are seeing the tail end of the change (in new designs) as even with huge arrays, getting enough space to support propulsion
is not reasonable both from a physics and an economic point of view. Now if someone comes out with a battery
that is reasonable cost and holds 1/4 the energy of a gallon of diesel
, it likely will be the end of the sailboat as the most common cruising boat. If you could start a trip with 400-500miles worth of range 80% of hull speed
and supplement that with 30-40miles of range per day (assuming most of the boat covered in panels). Most coastal cruisers would likely switch over and coastal cruisers buy the majority of new boats. Assuming you could drop back to 4-5kts and bump the range to 800-1000miles and gain 60-80miles per day from the solar (lower speed is typically more efficient), you are likely to see even long distance cruisers start to make the switch.
Yes, there will still be sailboats but honestly, I would say 80-90% choose sail not because of a love of sailing but because it's more cost effective (even if you never raise the sails).
Of course the big issue is batteries provide nothing close to these ranges and solar arrays large enough for even modest daily power generation conflict with using sail.