Hot dry rock geothermal energy as a separate state from that of the continuum of permeable rock—just as one would consider a completely closed faucet as distinct from one that is open to any degree, whether the flow be a trickle or a flood. In the same way, HDR technology should be regarded as totally distinct from EGS. A definitive book on HDR development, including a full account of the experiments at Fenton Hill, was published by Springer-Verlag in April 2012. Hot dry rock geothermal energy Hot dry rock (HDR) is an abundant source of geothermal energy available for use. A vast store of thermal
Notes from the Underground (Hollywood Undead album) 3rd song off of "Notes From The Underground's" "Another Way Out" was the official theme song for WWE's pay-per-view event Payback on June 16, 2013. The music video for "Dead Bite" was released on August 20, 2013. Much of the music on this album remains rooted in hip-hop. Notes from the Underground received generally positive reviews from music critics. Rick Florino of Artistdirect gave "Notes from the Underground" 5 out of 5 stars, noting that it is the best album of 2013 and best album Hollywood Undead has done to date, describing that the album "practically bubbles over with intoxicating,