From starwars.com :
Count Dooku's solar sailer is a hybrid of obscure technologies, its core body being a modified Punworcca 116-class sloop while the sail was provided by the Count himself. Geonosian engineers, who have long had a history of designing atmospheric sailing vessels, had no problem merging the two into the finished craft.
The term solar sail is a misnomer, since Count Dooku's interstellar sloop uses an as-yet unknown brand of energetic propulsion far more exotic than stellar radiation. Dooku acquired the delicate and ancient sail from mysterious Gree artisans, who developed a technology that harnesses supralight emissions for interstellar travel.
The solar sailer, like other Geonosian ships, uses a sophisticated array of narrow tractor/repulsor beams as offensive grapples and steering aids when in flight, affording the vessel an impressive maneuverability.
Well...it's been Xplained a bit how it works.......other than that, well...it's something of GL's mystery. If we would know the rest, we could build it for real.
Besides.....i don't c the advantages it has comparing to other ships with normal hyperdrives. I imagien it's not very good in direct shootings either.....