Edit: Thank you so much, everyone, for answering!
Boats don't have enough usable surface area for solar panels to propel them at a sustained useful speed (especially not at night or in a storm). Most sailboats do now have small solar panels to power lights and electronics. Hybrid propulsion systems are available, although expensive.
We lived aboard a catamaran with 600W of solar and it was enough to charge our banks and make water.
> more resilient to external conditions
The sea is really big and very powerful. If you are on it long enough you'll see some terrifying stuff. The boats being built today aren't really designed for those conditions. They were designed to be sailed smarter by using modern forecasting and satellite weather tracking. Going out blind and hoping you don't run into a tropical storm is rare these days.
We do. One of the main points in the article is that this particular yacht is old, was made using materials and techniques that aren’t in general use anymore, and thus the skills needed to maintain it are gradually dying out.
solar power instead of sails: A sunny day is about ½ HP per square yard of deck for a few hours. A 37 foot sailboat might get you about 15 square yards of deck if you really covered it, so < 10HP. Said boat might have a 40HP diesel for getting about. I can't say how many horsepower the sails make, but the boat I'm thinking of definitely has more sail power than engine power. (Pacific Seacraft 37).
That said, if you aren't planning to survive an ocean, but rather plan to have a pleasant day on a canal or a pond, an electric boat would be an excellent choice (though I'd just use batteries instead of solar) and are available.
Modern materials like composites have pluses and minuses compared to metal or wood. One of the huge minuses is repairability and structural strength for long spans.
Solar power for propulsion works for small vehicles, but not well for larger ones where energy density is important. Or on cloudy days and at night.
In the boating world weight is less of an issue, but in aviation composites often end up weighing more than aluminum, especially in the first batch. They also have temperature issues over about 300 mph, compared to Mach 2+ for aluminum.
It sounds like this boat restoration was ill-advised, but that really depends on their long-term goals.
At $1.5 million and a 23 MPH cruising speed, there probably won't be a lot of these built. I'm definitely curious to see if more demand for these drives the price down.
[1] https://www.popularmechanics.com/science/energy/a28834625/so...
Rain, wind and thunderstorms also damage the boat.
Racers will keep using carbon fibre.
Tûranor PlanetSolar is a 31m catamaran with over 500 square metres of solar panels. I think I'm right in saying that its cruising speed is slower than any regular yacht. A big racing yacht is multiple times faster.
What I'd be interested in seeing is if a big wind turbine could be put on a yacht, rather than sails. One fun advantage is that it should be able to travel directly into the wind.