The multi-million dollar solar powered yacht pictured below has completed circling the world, taking 585 days to complete the voyage.
Meanwhile, this past January, 2012, another "solar powered" yacht completed the voyage in a record 46 days, averaging almost 30 miles per hour. http://www.worldrecordsacademy.org/travel/fastest_yacht_voyage_around_the_world_Yachting_crew_sets_%20world_record_112674.html
That vessel was powered by sails. Such is the primitive state of solar powered technology in 2012.
The MS Turanor PlanetSolar, the world's largest solar boat ever built, arrives in the harbour of Monaco after it has achieved the first around-the-world journey using solar energy in 585 days, Friday, May 4, 2012.
The five sailors are : Raphael Domjan of Switzerland, founder and expedition leader, Patrick Marchesseau of France, Erwann le Rouzic of France, Jens Langwasser of Germany and Christian Oechsenbeim of Switzerland. (AP Photo/Bruno Bebert)...