Hot dry rock geothermal energy Hot dry rock geothermal energy Hot dry rock (HDR) is an abundant source of geothermal energy available for use. A vast store of thermal energy is contained within hot - but essentially dry - impervious crystalline basement rocks found almost everywhere deep beneath the earth’s surface. A concept for the extraction of useful amounts of geothermal energy from HDR originated at the Los Alamos National Laboratory in 1970, and Laboratory researchers were awarded a U.S. patent covering it. Although often confused with the relatively limited hydrothermal resource already commercialized to a large extent, HDR geothermal energy is very different. Whereas
Notes from the Underground (Hollywood Undead album) much fun they had doing without the label telling them what to do, he explained this record will be more like "Swan Songs" than "American Tragedy". He also revealed the album will be released on January 8, 2013. On December 11, the band announced that they will embark on a headlining tour titled "The Underground Tour", to promote "Notes from the Underground". Tour dates range from January 8, 2013, to January 23, starting in Hollywood, California. A video was released in promotion of the upcoming tour. On October 29, 2012, the first official single from "Notes from the Underground", titled