Gemasolar (2011)
Spain's Gemasolar plant near Seville became the first commercial CSP plant to use molten salt thermal storage. The 19.9 MW plant can generate electricity for 15 hours after the sun sets, running around the clock in summer.
Proved that solar thermal with storage could deliver firm, dispatchable power, not just daytime electricity.
Became the reference design for CSP with storage, though high costs limited replication.
247Solar's system is a successor to this concept, replacing molten salt with ceramic pellets and simplifying the design.
