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
What Is Truth What Is Truth "What Is Truth" is a single by American country music artist Johnny Cash released in February 1970. Generally viewed as a protest song, a rarity in country music at the time, the simple criticism of the Vietnam War, and war in general, as well as the stereotypical view of many politically liberal hippies made the song a major crossover hit. The song peaked at number 3 on the "Billboard" Hot Country Singles. It also became Cash's 12th Top 40 single on the Hot 100 chart, peaking at number 19, and his 2nd Top 10 single on the