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 2.0". "Sold My Soul to Yo Mama" (a track made by Linkin Park turntablist and sampler Joe Hahn, which includes samples from songs "Points of Authority" and "Papercut"), was released exclusively for "LP Underground 4.0". "Announcement Service Public" and "QWERTY" are found in the "LP Underground 6.0". "Hunger Strike", a song by Temple of the Dog, was performed by its lead singer Chris Cornell (whom the band toured with), and features a surprise guest appearance by Linkin Park lead vocalist Chester Bennington. Inside the physical CD, a leaflet can be found, inside which includes a free trial for a membership