All systems use hydrogen as working medium for the Stirling engine and have implemented the new high efficient and low cost ceramic cavity."During 2004 the erection of the 3 country reference units was completed (Seville, Odeillo, Würzburg) and all the systems were put into operation. All systems use hydrogen as working medium for the Stirling engine and have implemented the new high efficient and low cost ceramic cavity. The units in Seville and Würzburg are selling the generated power under the Spanish and German grid feed-in tariffs." » original news (via hugg.com)
