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
Songs from the Underground at LP Underground, as well as a limited free download of a live version of "Crawling", featuring Chris Cornell. Songs from the Underground Songs from the Underground is the second extended play released to the public by American rock band Linkin Park. It features songs previously released through the Linkin Park Underground fan club, as well as two previously unreleased live tracks from Projekt Revolution. "Songs from the Underground" features numerous songs released through Linkin Park Underground, the band's official fan club, as well as two live tracks from Projekt Revolution 2008. "And One" and "Part of Me" were included